SC 13D/A

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D/A

Under the Securities Exchange Act of 1934*

(Amendment No. 1)

Sunesis Pharmaceuticals, Inc.

(Name of Issuer)

Common Stock, $0.0001 Par Value

(Title of Class of Securities)

867328 50 2

(CUSIP Number)

Scott A. Arenare, Esq.

Managing Director and General Counsel

Warburg Pincus LLC

466 Lexington Avenue

New York, New York 10017

(212) 878-0600

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

March 17, 2006

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box:  ¨

NOTE:   Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 240.13d-7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 26928A 20 0 Page 2 of 13 pages

1	NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only) Warburg, Pincus Equity Partners, L.P.                                                     I.R.S. #13-3986317
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)  ¨ (b)  x
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)	¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7    SOLE VOTING POWER       -0-
	8    SHARED VOTING POWER       3,868,421
	9    SOLE DISPOSITIVE POWER       -0-
	10    SHARED DISPOSITIVE POWER       3,868,421

11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,868,421
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions)	¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 13.1%
14	TYPE OF REPORTING PERSON (See Instructions) PN

SCHEDULE 13D

CUSIP No. 867328 50 2 Page 3 of 13 pages

1	NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only) Warburg Pincus & Co.                                                      I.R.S. #13-6358475
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)  ¨ (b)  x
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) N/A
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)	¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION New York

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7    SOLE VOTING POWER       -0-
	8    SHARED VOTING POWER       3,868,421
	9    SOLE DISPOSITIVE POWER       -0-
	10    SHARED DISPOSITIVE POWER       3,868,421

11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,868,421
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions)	¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 13.1%
14	TYPE OF REPORTING PERSON (See Instructions) PN

SCHEDULE 13D

CUSIP No. 867328 50 2 Page 4 of 13 pages

1	NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only) Warburg Pincus LLC                                                     I.R.S. #13-3536050
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)  ¨ (b)  x
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) N/A
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)	¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION New York

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7    SOLE VOTING POWER       -0-
	8    SHARED VOTING POWER       3,868,421
	9    SOLE DISPOSITIVE POWER       -0-
	10    SHARED DISPOSITIVE POWER       3,868,421

11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,868,421
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions)	¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 13.1%
14	TYPE OF REPORTING PERSON (See Instructions) OO

SCHEDULE 13D

CUSIP No. 867328 50 2 Page 5 of 13 pages

1	NAMES OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only) Warburg Pincus Partners LLC                                                     I.R.S. #13-4069737
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a)  ¨ (b)  x
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) N/A
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)	¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION New York

NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH	7    SOLE VOTING POWER       -0-
	8    SHARED VOTING POWER       3,868,421
	9    SOLE DISPOSITIVE POWER       -0-
	10    SHARED DISPOSITIVE POWER       3,868,421

11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,868,421
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions)	¨
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 13.1%
14	TYPE OF REPORTING PERSON (See Instructions) OO

This Amendment No. 1 to Schedule 13D (this “Amendment”) is being filed on behalf of Warburg, Pincus Equity Partners, L.P., a Delaware limited partnership (together with two affiliated entities, “WPEP”), Warburg Pincus LLC, a New York limited liability company (“WP LLC”), Warburg Pincus & Co., a New York general partnership (“WP”) and Warburg Pincus Partners LLC, a New York limited liability company and a subsidiary of WP (“WPP LLC”). The holdings of Common Stock of WPEP, WP LLC, WP and WPP LLC include certain shares of Common Stock which may be deemed to be beneficially owned by Warburg, Pincus Netherlands Equity Partners I, C.V. (“WPNEP I”) and Warburg, Pincus Netherlands Equity Partners III, C.V. (“WPNEP III” and, together with WPEP and WPNEP I, the “Investors”). WPEP, WP, WP LLC, WPP LLC are collectively referred to as the “Warburg Pincus Reporting Persons”. This Amendment relates to the common stock, par value $0.0001 per share (the “Common Stock”), of Sunesis Pharmaceuticals, Inc., a Delaware corporation (the “Company”). Charles R. Kaye and Joseph P. Landy are Managing General Partners of WP and Managing Members of WP LLC and may be deemed to control the Warburg Pincus Reporting Persons. Messrs. Kaye and Landy disclaim beneficial ownership of all shares held by the Warburg Pincus Reporting Persons.

The Warburg Pincus Reporting Persons are filing this Amendment because they have, pursuant to a certain Common Stock and Warrant Purchase Agreement, dated March 17, 2006, by and among the Company, the Investors and the other parties signatory thereto (the “Purchase Agreement”), acquired certain shares of the Common Stock and certain warrants to purchase shares of the Common Stock, which are exercisable immediately (the “Common Stock Warrants”). As a result of this acquisition,

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the percentage of shares of the Common Stock of which the Reporting Persons may be deemed to be the beneficial owners has increased by more than one percent.

Item 3. Source and Amount of Funds or Other Consideration.

Item 3 is hereby amended by inserting the following at the end thereof:

The Investors purchased 805,153 shares of Common Stock and 241,546 Common Stock Warrants (collectively, the “New Securities”) pursuant to the Purchase Agreement at a purchase price of $6.2475 per share and associated Common Stock Warrant; it being understood that the aggregate fair market value of the Common Stock Warrants, if issued apart from the Common Stock, was $30,193 ($0.125 per Common Stock Warrant). The aggregate purchase price paid by the Investors for the New Securities was $5,030,193. All of the funds required to acquire the New Securities were obtained from the working capital of the Investors.

Item 4. Purpose of Transaction.

Item 4 is hereby amended by replacing the first sentence thereof in its entirety with the following:

The acquisition by the Warburg Pincus Reporting Persons of the Common Stock and Common Stock Warrants was effected because of the Warburg Pincus Reporting Persons’ belief that the Common Stock represented, and continues to represent, an attractive investment.

Item 5. Interest in Securities of the Issuer.

Items 5(a) and 5(b) are hereby amended by replacing them in their entirety with the following:

(a) As of March 17, 2006, each of the Warburg Pincus Reporting Persons may be deemed to beneficially own 3,868,421 shares of the Common Stock,

Page 7 of 13 pages

representing 13.1% of the outstanding Common Stock, based on: the 21,945,375 shares reported by the Company in the Purchase Agreement as outstanding on March 17, 2006 prior to closing under the Purchase Agreement, the 7,246,377 shares of Common Stock issued pursuant to the Purchase Agreement and the 241,546 shares of Common Stock for which the Warburg Pincus Reporting Persons are entitled to subscribe pursuant to the Common Stock Warrants.

(b) Each of the Warburg Pincus Reporting Persons shares the power to vote or to direct the vote and to dispose or to direct the disposition of the 3,868,421 shares of Common Stock it may be deemed to beneficially own.

The Warburg Pincus Reporting Persons are making this single, joint filing because they may be deemed to constitute a “person” or “group” within the meaning of Section 13(d)(3) of the Exchange Act. The filing of this Amendment shall not be construed as an admission of such beneficial ownership or that the Warburg Pincus Reporting Persons constitute a person or group.

The last sentence of Item 5(c) is hereby amended by replacing it in its entirety with the following:

(c) On March 17, 2006, the Investors purchased 805,153 shares of Common Stock and 241,546 Common Stock Warrants at a purchase price of $6.2475 per share and associated Common Stock Warrant, pursuant to the Purchase Agreement. The aggregate purchase price paid by the Warburg Pincus Reporting Persons was $5,030,193. No other transactions in the Common Stock were effected during the past sixty days by the Warburg Pincus Reporting Persons or any of the persons set forth on Schedule I hereto. Charles R. Kaye and Joseph P. Landy are Managing General Partners of WP and

Page 8 of 13 pages

Managing Members of WP LLC and may be deemed to control the Warburg Pincus Reporting Persons. Messrs. Kaye and Landy disclaim beneficial ownership of all shares held by the Warburg Pincus Reporting Persons.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer.

Item 6 is hereby amended by inserting the following at the end thereof:

The Investors entered into the Purchase Agreement pursuant to which the Company agreed to issue and sell and the Investors agreed to purchase the New Securities on the Closing Date. The parties executed the Purchase Agreement in reliance upon the exemption from securities registration afforded by the provisions of Regulation D, as promulgated by the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended. Contemporaneously with the acquisition, the Company and the Investors also executed a Registration Rights Agreement, a description of which follows. This summary of the Purchase Agreement is qualified in its entirety by reference to the Purchase Agreement, which is attached hereto, as Exhibit C.

Pursuant to the Common Stock Warrants, the Investors are entitled to subscribe for and purchase in the aggregate 241,546 fully paid and nonassessable shares of the Common Stock, at an exercise price per share equal to $6.21. The Investors may exercise this right in whole or in part, at any time and from time to time from March 17, 2006 (the “Date of Grant”) until the seven year anniversary of the Date of Grant. This summary of the Common Stock Warrants is qualified in its entirety by reference to the Common Stock Warrants, which are attached hereto, as Exhibit D.

Page 9 of 13 pages

Pursuant to the Registration Rights Agreement (the “Registration Rights Agreement”), dated as of March 17, 2006, by and among the Company, the Investors and other parties signatory thereto, the Investors have been granted certain registration rights. The following summarizes certain provisions of the Registration Rights Agreement and is qualified in its entirety by reference to the Registration Rights Agreement, which is attached hereto as Exhibit E:

Pursuant to Section 2(a) of the Registration Rights Agreement, the Company will file with the SEC a registration statement on Form S-1 no later than 35 days after the Closing (as defined in the Purchase Agreement) (the “Filing Deadline”). The registration statement will cover the resale of the shares of the Common Stock issued pursuant to the Purchase Agreement (the “Shares”) and the shares of the Common Stock issuable upon exercise of the Common Stock Warrants (the “Warrant Shares”), as well as additional shares of the Common Stock resulting from stock splits, stock dividends or similar transactions with respect to the Shares (together with the Shares and the Warrant Shares, the “Registrable Securities”).

If a registration statement covering the Registrable Securities is not filed with the SEC on or prior to the Filing Deadline, the Company will make pro rata payments to each Investor in an amount equal to 1% of the aggregate amount invested by each Investor for each 30 day period or pro rata for any portion thereof following the Filing Deadline for which no registration statement is filed with respect to the Registrable Securities, provided that these payments, together with the amount of any

Page 10 of 13 pages

liquidated damages previously paid pursuant to any provision of the Registration Rights Agreement, will not exceed 10% of the aggregate amount invested by each Investor. These payments will be made in cash.

If a registration statement covering the Registrable Securities is not declared effective by the SEC within (a) 35 days after the Filing Date if the SEC will have informed the Company that no review of the registration statement will be made or (b) 105 days after the Filing Date if the SEC will have so informed the Company, the Company will make pro rata payments to each Investor in an amount equal to 1% of the aggregate amount invested by each Investor for each 30 day period or pro rata for any portion thereof following the date by which the registration statement should have been effective, provided that these payments, together with the amount of any liquidated damages previously paid pursuant to any provision of the Registration Rights Agreement, will not exceed 10% of the aggregate amount invested by each Investor. These payments will be made in cash.

If on any day after the date of effectiveness of a registration statement covering the Registrable Securities, sales of all the Registrable Securities required to be included on the registration statement cannot be made pursuant to the registration statement, the Company will make pro rata payments to each Investor in an amount equal to one percent of the aggregate amount invested by each Investor for each 30 day period or pro rata for any portion thereof following the date by which the sales of Registrable Securities under the registration statement cannot be made; provided that these payments, together with the amount of any liquidated damages previously paid

Page 11 of 13 pages

pursuant to any provision of this Agreement, will not exceed 10% of the aggregate amount invested by each Investor. These payments will be made in cash.

Pursuant to a Lock-up Letter Agreement, dated as of March 17, 2006, by and among the Company and the Investors (the “Lock-up Agreement”), without the prior written consent of the Company, the Investors have agreed that they will not, directly or indirectly, (a) offer for sale, sell, pledge or otherwise dispose of (or enter into any transaction or device that is designed to, or could be expected to, result in the disposition by any person at any time in the future of) any shares of Common Stock (including, without limitation, shares of Common Stock that may be deemed to be beneficially owned by the Investors and shares of the Common Stock that may be issued upon exercise of any option or warrant) or securities convertible into or exchangeable for Common Stock, or (b) enter into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic benefits or risks of ownership of shares of Common Stock for a period of 60 days after March 17, 2006, subject to specified exceptions and subject to extension of the lock-up period pending the effectiveness of the registration statement filed by the Company under the Registration Rights Agreement. This summary of the Lock-up Agreement is qualified in its entirety by reference to the Lock-up Agreement, which is attached hereto, as Exhibit F.

Item 7. Material to Be Filed as Exhibits.

In addition to the exhibits filed with the original Schedule 13D, the following additional exhibits are filed herewith:

Exhibit C Common Stock and Warrant Purchase Agreement, dated March 17, 2006, by and among the Company and the Investors.

Page 12 of 13 pages

Exhibit D	Warrants to Purchase Shares of Common Stock of Sunesis Pharmaceuticals, Inc., dated March 17, 2006.
Exhibit E	Registration Rights Agreement, dated March 17, 2006, by and among the Company and the Investors
Exhibit F	Lock-up Letter Agreement, dated March 17, 2006, by and among the Company and the Investors.

Page 13 of 13 pages

SIGNATURES

After reasonable inquiry and to the best of our knowledge and belief, the undersigned certify that the information set forth in this statement is true, complete and correct.

Dated: March 22, 2006		WARBURG, PINCUS EQUITY PARTNERS, L.P.
			By:	Warburg Pincus Partners LLC,
				its General Partner
				By:	Warburg Pincus & Co.,
					its Managing Member
		By:	/s/ Scott A. Arenare
			Name:	Scott A. Arenare
			Title:	Partner
Dated:	March 22, 2006	WARBURG PINCUS & CO.
		By:	/s/ Scott A. Arenare
			Name:	Scott A. Arenare
			Title:	Partner
Dated:	March 22, 2006	WARBURG PINCUS LLC
		By:	/s/ Scott A. Arenare
			Name:	Scott A. Arenare
			Title:	Member
Dated:	March 22, 2006	WARBURG PINCUS PARTNERS LLC
			By:	Warburg Pincus & Co.,
				its Managing Member
		By:	/s/ Scott A. Arenare
			Name:	Scott A. Arenare
			Title:	Partner

SCHEDULE I

Set forth below is the name, position and present principal occupation of each of the general partners of Warburg Pincus & Co. (“WP”) and members of Warburg Pincus LLC (“WP LLC”). The sole general partner of Warburg Pincus Private Equity IX, L.P. (“WP IX”) is Warburg Pincus IX, LLC (“WP IX LLC”), an indirect subsidiary of WP. WP IX, WP IX LLC, WP and WP LLC are hereinafter collectively referred to as the “Reporting Entities”. Except as otherwise indicated, the business address of each of such persons is 466 Lexington Avenue, New York, New York 10017, and each of such persons is a citizen of the United States.

GENERAL PARTNERS OF WP

NAME	PRESENT PRINCIPAL OCCUPATION IN ADDITION TO POSITION WITH WP, AND POSITIONS WITH THE REPORTING ENTITIES
Joel Ackerman	Partner of WP; Member and Managing Director of WP LLC
Scott A. Arenare	Partner of WP; Member and Managing Director of WP LLC
Gregory Back	Partner of WP; Member and Managing Director of WP LLC
David Barr	Partner of WP; Member and Managing Director of WP LLC
Harold Brown	Partner of WP; Member and Managing Director of WP LLC
Sean D. Carney	Partner of WP; Member and Managing Director of WP LLC
Mark Colodny	Partner of WP; Member and Managing Director of WP LLC
David A. Coulter	Partner of WP; Member and Managing Director of WP LLC
Timothy J. Curt	Partner of WP; Member and Managing Director of WP LLC
W. Bowman Cutter	Partner of WP; Member and Managing Director of WP LLC
Cary J. Davis	Partner of WP; Member and Managing Director of WP LLC
Michael Graff	Partner of WP; Member and Managing Director of WP LLC
Patrick T. Hackett	Partner of WP; Member and Managing Director of WP LLC
Jeffrey A. Harris	Partner of WP; Member and Managing Director of WP LLC
Stewart J. Hen	Partner of WP; Member and Managing Director of WP LLC
William H. Janeway	Partner of WP; Member and Vice Chairman of WP LLC
Julie A. Johnson Staples	Partner of WP; Member and Managing Director of WP LLC
Chansoo Joung	Partner of WP; Member and Managing Director of WP LLC

Peter R. Kagan	Partner of WP; Member and Managing Director of WP LLC
Charles R. Kaye	Managing General Partner of WP; Managing Member and Co-President of WP LLC
Henry Kressel	Partner of WP; Member and Managing Director of WP LLC
Kevin Kruse	Partner of WP; Member and Managing Director of WP LLC
Joseph P. Landy	Managing General Partner of WP; Managing Member and Co-President of WP LLC
Sidney Lapidus	Partner of WP; Member and Managing Director of WP LLC
Kewsong Lee	Partner of WP; Member and Managing Director of WP LLC
Jonathan S. Leff	Partner of WP; Member and Managing Director of WP LLC
Philip Mintz	Partner of WP; Member and Managing Director of WP LLC
Rodman W. Moorhead III	Partner of WP; Member and Managing Director of WP LLC
James Neary	Partner of WP; Member and Managing Director of WP LLC
Bilge Ogut	Partner of WP; Member and Managing Director of WP LLC
Dalip Pathak	Partner of WP; Member and Managing Director of WP LLC
Lionel I. Pincus	Partner of WP; Member and Chairman of WP LLC
Michael F. Profenius	Partner of WP; Member and Managing Director of WP LLC
Stan Raatz	Partner of WP; Member and Managing Director of WP LLC
Henry B. Schacht	Partner of WP; Member and Managing Director of WP LLC
Steven G. Schneider	Partner of WP; Member and Managing Director of WP LLC
Mimi Strouse	Partner of WP; Member and Managing Director of WP LLC
Patrick Sullivan	Partner of WP; Member and Managing Director of WP LLC
Barry Taylor	Partner of WP; Member and Managing Director of WP LLC
Christopher H. Turner	Partner of WP; Member and Managing Director of WP LLC
John L. Vogelstein	Partner of WP; Member and Vice Chairman of WP LLC
John R. Vrolyk	Partner of WP; Member and Managing Director of WP LLC
Elizabeth H. Weatherman	Partner of WP; Member and Managing Director of WP LLC

David J. Wenstrup	Partner of WP; Member and Managing Director of WP LLC
Rosanne Zimmerman	Partner of WP; Member and Managing Director of WP LLC
Pincus & Company LLC*
NL & Co.**
Warburg Pincus VP Partnership, L.P.***

* New York limited liability company; primary activity is ownership interest in WP and WP LLC

** New York limited partnership; primary activity is ownership interest in WP

*** Delaware limited partnership; primary activity is ownership interest in WP

MEMBERS OF WP LLC

NAME	PRESENT PRINCIPAL OCCUPATION IN ADDITION TO POSITION WITH WP LLC, AND POSITIONS WITH THE REPORTING ENTITIES
Joel Ackerman	Member and Managing Director of WP LLC; Partner of WP
Scott A. Arenare	Member and Managing Director of WP LLC; Partner of WP
Gregory Back	Member and Managing Director of WP LLC; Partner of WP
David Barr	Member and Managing Director of WP LLC; Partner of WP
Harold Brown	Member and Managing Director of WP LLC; Partner of WP
Sean D. Carney	Member and Managing Director of WP LLC; Partner of WP
Stephen John Coates (1)	Member and Managing Director of WP LLC
Mark Colodny	Member and Managing Director of WP LLC; Partner of WP
David A. Coulter	Member and Managing Director of WP LLC; Partner of WP
Timothy J. Curt	Member and Managing Director of WP LLC; Partner of WP
W. Bowman Cutter	Member and Managing Director of WP LLC; Partner of WP
Cary J. Davis	Member and Managing Director of WP LLC; Partner of WP
Rajiv Ghatalia (2)	Member and Managing Director of WP LLC
Michael Graff	Member and Managing Director of WP LLC; Partner of WP
Patrick T. Hackett	Member and Managing Director of WP LLC; Partner of WP
Jeffrey A. Harris	Member and Managing Director of WP LLC; Partner of WP
Stewart J. Hen	Member and Managing Director of WP LLC; Partner of WP
William H. Janeway	Member and Vice Chairman of WP LLC; Partner of WP
Julie A. Johnson Staples	Member and Managing Director of WP LLC; Partner of WP
Chansoo Joung	Member and Managing Director of WP LLC; Partner of WP
Peter R. Kagan	Member and Managing Director of WP LLC; Partner of WP
Charles R. Kaye	Managing Member and Co-President of WP LLC; Managing General Partner of WP
Rajesh Khanna (2)	Member and Managing Director of WP LLC
Henry Kressel	Member and Managing Director of WP LLC; Partner of WP
Kevin Kruse	Member and Managing Director of WP LLC; Partner of WP
Joseph P. Landy	Managing Member and Co-President of WP LLC; Managing General Partner of WP
Sidney Lapidus	Member and Managing Director of WP LLC; Partner of WP
Kewsong Lee	Member and Managing Director of WP LLC; Partner of WP
Jonathan S. Leff	Member and Managing Director of WP LLC; Partner of WP
Jeff Leng (3)	Member and Managing Director of WP LLC
David Li (4)	Member and Managing Director of WP LLC
Nicholas J. Lowcock (1)	Member and Managing Director of WP LLC
Philip Mintz	Member and Managing Director of WP LLC; Partner of WP
Rodman W. Moorhead III	Member and Managing Director of WP LLC; Partner of WP
James Neary	Member and Managing Director of WP LLC; Partner of WP
Bilge Ogut	Member and Managing Director of WP LLC; Partner of WP
Dalip Pathak	Member and Managing Director of WP LLC; Partner of WP
Lionel I. Pincus	Member and Chairman of WP LLC; Partner of WP
Pulak Chandan Prasad (2)	Member and Managing Director of WP LLC

Michael F. Profenius	Member and Managing Director of WP LLC; Partner of WP
Stan Raatz	Member and Managing Director of WP LLC; Partner of WP
Henry B. Schacht	Member and Managing Director of WP LLC; Partner of WP
Steven G. Schneider	Member and Managing Director of WP LLC; Partner of WP
Joseph C. Schull (5)	Member and Managing Director of WP LLC
Mimi Strouse	Member and Managing Director of WP LLC; Partner of WP
Patrick Sullivan	Member and Managing Director of WP LLC; Partner of WP
Chang Q. Sun (4)	Member and Managing Director of WP LLC
Barry Taylor	Member and Managing Director of WP LLC; Partner of WP
Christopher H. Turner	Member and Managing Director of WP LLC; Partner of WP
Simon Turton (1)	Member and Managing Director of WP LLC
John L. Vogelstein	Member and Vice Chairman of WP LLC; Partner of WP
John R. Vrolyk	Member and Managing Director of WP LLC; Partner of WP
Elizabeth H. Weatherman	Member and Managing Director of WP LLC; Partner of WP
David J. Wenstrup	Member and Managing Director of WP LLC; Partner of WP
Peter Wilson (1)	Member and Managing Director of WP LLC
Jeremy S. Young (1)	Member and Managing Director of WP LLC
Rosanne Zimmerman	Member and Managing Director of WP LLC; Partner of WP
Pincus & Company LLC*

(1) Citizen of United Kingdom

(2) Citizen of India

(3) Citizen of China

(4) Citizen of Hong Kong

(5) Citizen of Canada

* New York limited liability company; primary activity is ownership interest in WP and WP LLC

As of February 15, 2006

EX-99.C

Exhibit C

COMMON STOCK AND WARRANT PURCHASE AGREEMENT

THIS COMMON STOCK AND WARRANT PURCHASE AGREEMENT (“Agreement”) is made as of the 17^th day of March 2006 by and among Sunesis Pharmaceuticals, Inc., a Delaware corporation (the “Company”), and the other Persons set forth on the signature pages hereto (each an “Investor” and collectively the “Investors”).

Recitals

A. The Company and the Investors are executing and delivering this Agreement in reliance upon the exemption from securities registration afforded by the provisions of Regulation D (“Regulation D”), as promulgated by the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (the “Securities Act”);

B. The Investors wish to purchase from the Company, and the Company wishes to sell and issue to the Investors, upon the terms and subject to the conditions set forth in this Agreement, an aggregate of 7,246,377 shares (the “Shares”) of the Company’s common stock, par value $0.0001 per share (the “Common Stock”) and warrants (the “Warrants”) to purchase an aggregate of 2,173,914 shares of Common Stock (subject to adjustment pursuant to Section 4 of the Warrants) in the form of Exhibit A hereto for a purchase price of $6.2475 per Share and associated Warrant, for an aggregate purchase price of $45,271,740.43, it being understood that the aggregate fair market value of the warrants, if issued apart from the Shares, is $271,739.26;

C. Contemporaneous with the sale of the Shares, the parties hereto will execute and deliver a Registration Rights Agreement, in the form attached hereto as Exhibit B (the “Registration Rights Agreement”), pursuant to which the Company will agree to provide certain registration rights under the Securities Act; and

D. This Agreement shall be binding upon the Company and the Investors only upon delivery of the signatures pages hereto by the Company and the Investors.

Agreement

In consideration of the mutual promises made herein and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. Definitions. In addition to those terms defined above and elsewhere in this Agreement, for the purposes of this Agreement, the following terms shall have the meanings set forth below:

“Affiliate” means, with respect to any Person, any other Person which directly or indirectly through one or more intermediaries controls, is controlled by, or is under common control with, such Person.

“Business Day” means a day, other than a Saturday or Sunday, on which banks in New York City are open for the general transaction of business.

“Confidential Information” means trade secrets, confidential information and know-how (including but not limited to ideas, formulae, compositions, processes, procedures and techniques, research and development information, performance specifications, support documentation, drawings, specifications, designs, business and marketing plans, and supplier lists and related information).

“Effective Date” means the date on which the Registration Statement is declared effective by the SEC.

“Effectiveness Deadline” means the date on which the Registration Statement is required to be declared effective by the SEC under the terms of the Registration Rights Agreement.

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“Intellectual Property” means all of the following: (i) patents, patent applications, patent disclosures and inventions (whether or not patentable and whether or not reduced to practice); (ii) trademarks, service marks, trade dress, trade names, corporate names, logos, slogans and Internet domain names, together with all goodwill associated with each of the foregoing; (iii) copyrights and copyrightable works; and (iv) registrations, applications and renewals for any of the foregoing.

“Lockup Agreement” means a Lockup Agreement in the form of Exhibit C hereto.

“Material Adverse Effect” means an event, change or occurrence that, individually or together with any other event, change or occurrence, has a material adverse impact on the Company’s financial position, business, results of operations or prospects, excluding any event, change or occurrence resulting from the announcement or consummation of the transactions contemplated by the Transaction Documents.

“Nasdaq” means The Nasdaq Stock Market, Inc.

“Permitted Liens” means (i) mechanics’, carriers’, or workmen’s, repairmen’s or similar liens arising or incurred in the ordinary course of business, (ii) liens for taxes, assessments and other governmental charges that are not due and payable or which may hereafter be paid without penalty or which are being contested in good faith by appropriate proceedings

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and (iii) other imperfections of title or encumbrances, if any, that do not, individually or in the aggregate, materially impair the use or value of the property to which they relate.

“Person” means an individual, corporation, partnership, limited liability company, trust, business trust, association, joint stock company, joint venture, sole proprietorship, unincorporated organization, governmental authority or any other form of entity not specifically listed herein.

“Registration Statement” has the meaning set forth in the Registration Rights Agreement.

“SEC Filings” has the meaning set forth in Section 4.6.

“Securities” means the Shares, the Warrants and the Warrant Shares.

“Subsidiary” of any Person means another Person, an amount of the voting securities, other voting ownership or voting partnership interests of which is sufficient to elect at least a majority of its Board of Directors or other governing body (or, if there are no such voting interests, 50% or more of the equity interests of which) is owned directly or indirectly by such first Person.

“Transaction Documents” means this Agreement, the Registration Rights Agreement and the Warrants.

“Warrant Shares” mean the shares of Common Stock issuable upon exercise of the Warrants (including shares of Common Stock issuable upon adjustment pursuant to Section 4 of the Warrants).

2. Purchase and Sale of the Shares and the Warrants. Upon the terms and subject to the conditions set forth in this Agreement, at the Closing, each of the Investors shall, severally and not jointly, purchase, and the Company shall sell and issue to the Investors, the Shares and the Warrants in the respective amounts set forth below the Investors’ names on the signature pages hereto.

3. Closing. The purchase and sale of the Shares and the Warrants pursuant to Section 2 shall take place at the offices of Latham & Watkins LLP, 135 Commonwealth Drive, Menlo Park, California 94025 on March 17, 2006, or at such other location and on such other date as the Company and the Investors shall mutually agree (which time and place are designated as the “Closing”). At the Closing, the Company shall deliver to each Investor a certificate or certificates representing the number of Shares and a Warrant for the number of shares of Common Stock each as set forth below such Investor’s name on the signature pages hereto against payment of the purchase price therefor by wire transfer of immediately available funds to a bank account designated by the Company.

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4. Representations and Warranties of the Company. The Company hereby represents and warrants to the Investors that, except as disclosed in the SEC Filings or as set forth in the schedules delivered herewith (collectively, the “Disclosure Schedules”):

4.1 Organization, Good Standing and Qualification. The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware and has all requisite corporate power and authority to carry on its business as now conducted and to own its properties. The Company is duly qualified to do business as a foreign corporation and is in good standing in each jurisdiction in which the conduct of its business or its ownership or leasing of property makes such qualification necessary, except where the failure to so qualify, individually or in the aggregate, would not have a Material Adverse Effect. To the Company’s knowledge, no proceeding has been instituted in any jurisdiction revoking, limiting or curtailing or seeking to revoke, limit or curtail, such power and authority or qualification. The Company has no Subsidiaries.

4.2 Authorization. The Company has full corporate power and authority and has taken all requisite action on the part of the Company, its officers, directors and stockholders necessary for (i) the authorization, execution and delivery of the Transaction Documents, (ii) the authorization of the performance of all obligations of the Company hereunder or thereunder and (iii) the authorization, issuance, sale and delivery of the Securities. The Transaction Documents constitute the legal, valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms, subject to bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights generally.

4.3 Capitalization. Schedule 4.3 sets forth as of the date hereof (a) the authorized capital stock of the Company; (b) the number of shares of capital stock issued and outstanding; (c) the number of shares of capital stock available for issuance pursuant to the Company’s stock plans; and (d) the number of shares of capital stock issuable and reserved for issuance pursuant to securities exercisable for, or convertible into or exchangeable for any shares of capital stock of the Company. All of the issued and outstanding shares of the Company’s capital stock have been duly authorized and validly issued and are fully paid, nonassessable and free of preemptive rights. No Person is entitled to pre-emptive or similar statutory or contractual rights with respect to any securities of the Company. There are no outstanding warrants, options, convertible securities or other rights, agreements or arrangements under which the Company is obligated to issue equity securities. Except as contemplated under this Agreement, there are no contracts, commitments, understandings or arrangements by which the Company is bound to issue additional shares of capital stock of the Company or options, securities or rights convertible into shares of capital stock of the Company. Except as provided in the Registration Rights Agreement, no Person has the right to require the Company to register any securities of the Company under the Securities Act, whether on a demand basis or in connection with the registration of securities of the Company for its own account or for the account of any other Person. The issue and sale of the Securities will not result in the right of any holder of Company securities to adjust the exercise, conversion or exchange price under such securities.

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4.4 Valid Issuance. The Shares and the Warrants have been duly and validly authorized and, when issued and paid for pursuant to this Agreement, will be validly issued, fully paid and nonassessable, and will be free of encumbrances and restrictions (other than those created by the Investors), except for restrictions on transfer set forth in the Transaction Documents or imposed by applicable securities laws. The Warrant Shares have been reserved for issuance and, upon issuance pursuant to the Warrants, will be duly and validly authorized and fully paid and nonassessable.

4.5 Consents. The execution, delivery and performance by the Company of the Transaction Documents and the offer, issuance and sale of the Securities and the Warrant Shares requires no consent of, action by or in respect of, or filing with, any Person, governmental body, agency, or official other than filings that have been made pursuant to applicable state securities laws and post-sale filings pursuant to applicable state and federal securities laws which the Company undertakes to file within the applicable time periods.

4.6 Delivery of SEC Filings. The Company has made available to the Investors through the EDGAR system, true and complete copies of (a) the Company’s Registration Statement on Form S-1 filed with the SEC on September 27, 2005 including all exhibits thereto and documents incorporated by reference therein (the “IPO Registration Statement”), (b) the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2005 filed with the SEC on November 14, 2005 including all exhibits thereto and documents incorporated by reference therein and (c) the Company’s Current Reports on Form 8-K filed with the SEC on November 14, 2005, January 6, 2006 and February 15, 2006 including all exhibits thereto and documents incorporated by reference therein (the “Periodic Filings” and, together with the IPO Registration Statement, the “SEC Filings”). The Periodic Filings are the only periodic filings required of the Company pursuant to the Exchange Act through the date hereof.

4.7 Use of Proceeds. The net proceeds of the sale of the Shares and the Warrants hereunder shall be used by the Company for working capital and general corporate purposes.

4.8 No Material Adverse Change. Since September 30, 2005, there has not been:

(i) any change in the consolidated assets, liabilities, financial condition or operating results of the Company from that reflected in the financial statements included in the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2005, except for changes in the ordinary course of business which would not have, individually or in the aggregate, a Material Adverse Effect;

(ii) any declaration or payment of any dividend, or any authorization or payment of any distribution, on any of the capital stock of the Company, or any redemption or repurchase of any securities of the Company (other than in connection with a termination of employment);

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(iii) any material damage, destruction or loss to any assets or properties of the Company;

(iv) any waiver, not in the ordinary course of business, by the Company of a material right or of a material debt owed to it;

(v) any change or amendment to the Company’s Certificate of Incorporation or Bylaws, or change to any material contract or arrangement by which the Company is bound or to which its assets or properties is subject;

(vi) any material labor difficulties or labor union organizing activities with respect to employees of the Company;

(vii) any transaction entered into by the Company other than in the ordinary course of business;

(viii) the loss of the services of any key employee, or material change in the composition or duties of the senior management of the Company; or

(ix) any other event or condition of any character that has had or would reasonably be expected to have a Material Adverse Effect.

4.9 SEC Filings. At the time of filing thereof, the SEC Filings complied as to form in all material respects with the requirements of the Exchange Act and did not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements made therein, in the light of the circumstances under which they were made, not misleading.

4.10 No Conflict, Breach, Violation or Default. Neither the execution, delivery and performance of the Transaction Documents by the Company nor the consummation of any of the transactions contemplated hereby (including without limitation the issuance and sale of the Securities) will conflict with or result in violation of any of the terms and provisions of the Company’s Certificate of Incorporation or Bylaws, both as in effect on the date hereof or will give rise to the right to terminate or accelerate the due date of any payment under or conflict with or result in a breach of any term or provision of, or constitute a default (or any event which with notice or lapse of time or both would constitute a default) under, or require any consent or waiver under or result in the execution or imposition of any lien, charge or encumbrance upon the properties or assets of the Company pursuant to the terms of any indenture, mortgage, deed of trust or other agreement or instrument to which the Company is a party or by which the Company is bound or to which any of its assets or properties is subject or any license, permit, statute, rule, regulation, judgment, decree or order of any governmental agency or body or any court, domestic or foreign, having jurisdiction over the Company or any of its assets or properties, other than a conflict, breach or default that would not have a Material Adverse Effect.

4.11 Tax Matters. The Company has timely prepared and filed all tax returns required to have been filed by the Company with all appropriate governmental agencies and

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timely paid all taxes shown thereon or otherwise owed by it, except as would not have a Material Adverse Effect. The charges, accruals and reserves on the books of the Company in respect of taxes for all fiscal periods are adequate in all material respects, and there are no material unpaid assessments against the Company. All taxes and other assessments and levies that the Company is required to withhold or to collect for payment have been duly withheld and collected and paid to the proper governmental entity or third party when due. There are no tax liens or claims pending or, to the Company’s knowledge, threatened against the Company or any of its assets or property, other than Permitted Liens. There are no tax audits or investigations pending, which if adversely determined would result in a Material Adverse Effect. There are no outstanding tax sharing agreements or other such arrangements between the Company and any other Person. The Company does not have any deferred compensation arrangements and has not paid or is not required to pay any deferred compensation which would be subject to Section 409A of the Internal Revenue Code.

4.12 Title to Properties. The Company has good and marketable title to all properties and assets owned by it, in each case free from liens, encumbrances and defects, other than Permitted Liens. The Company holds any leased real or Personal property under valid and enforceable leases. The Company does not own any real property.

4.13 Certificates, Authorities and Permits. The Company possesses adequate certificates, approvals, authorities or permits (“Permits”) issued by governmental agencies or bodies necessary to own, lease and license its assets and properties and conduct the business now operated by it, all of which are valid and in full force and effect, except where the lack of such Permits, individually or in the aggregate, would not have a Material Adverse Effect. The Company has performed in all material respects all of its material obligations with respect to such Permits and no event has occurred that allows, or after notice or lapse of time, would allow, revocation or termination thereof. The Company has not received any written notice of proceedings relating to the revocation or modification of any such certificate, authority or permit that, if determined adversely to the Company, would, individually or in the aggregate, have a Material Adverse Effect.

4.14 Labor Matters.

(a) The Company is not a party to or bound by any collective bargaining agreement. The Company has not violated in any material respect any laws, regulations, orders or contract terms, affecting the collective bargaining rights of employees, labor organizations or any laws, regulations or orders affecting employment discrimination, equal opportunity employment or employees’ health, safety, welfare, wages and hours.

(b) (i) There are no labor disputes existing, or to the Company’s knowledge, threatened, involving strikes, slow-downs, work stoppages, job actions, disputes, lockouts or any other disruptions of or by the Company’s employees, (ii) there are no unfair labor practices or petitions for election pending or, to the Company’s knowledge, threatened before the National Labor Relations Board or any other federal, state or local labor commission relating to the Company’s employees, (iii) no demand for recognition or certification heretofore made by any labor organization or group of employees is pending with respect to the Company and (iv) to the Company’s knowledge, the Company enjoys good labor and employee relations with its employees.

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(c) The Company is in compliance in all material respects with applicable laws respecting employment (including laws relating to classification of employees and independent contractors) and employment practices, terms and conditions of employment, wages and hours, and immigration and naturalization. No claims are pending against the Company before the Equal Employment Opportunity Commission or any other administrative body or in any court asserting any violation of Title VII of the Civil Rights Act of 1964, the Age Discrimination Act of 1967, 42 U.S.C. §§ 1981 or 1983 or any other federal, state or local law, statute or ordinance barring discrimination in employment.

(d) The Company is not a party to, or bound by, any employment or other contract or agreement that contains any severance, termination pay or change of control liability or obligation, including, without limitation, any “excess parachute payment,” as defined in Section 280G(b) of the Internal Revenue Code of 1986, as amended.

4.15 Intellectual Property.

(a) To the Company’s knowledge, all Intellectual Property of the Company is valid and enforceable. No Intellectual Property owned or licensed by the Company that is necessary for the conduct of Company’s business as currently conducted or as proposed to be conducted as described in the SEC Filings is involved in any cancellation, dispute or litigation, and, to the Company’s knowledge, no such action is threatened. No issued patent owned by the Company is involved in any interference, reissue, re-examination or opposition proceeding.

(b) All of the in-bound licenses and sublicenses and consent, royalty or other agreements concerning Intellectual Property which are necessary for the conduct of the Company’s business as currently conducted and as proposed to be conducted as described in the SEC Filings to which the Company is a party (other than generally commercially available, non-custom, off-the-shelf software application programs having a retail acquisition price of less than $50,000 per license) (collectively, “In-Bound License Agreements”) are, to the Company’s knowledge, valid and binding obligations of the Company, enforceable in accordance with their terms, except to the extent that enforcement thereof may be limited by bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance or other similar laws affecting the enforcement of creditors’ rights generally, and, to the Company’s knowledge, the Company is not in material breach of any of its obligations under any such In-Bound License Agreements.

(c) The Company owns or has the valid right to use all of the Intellectual Property that is necessary for the conduct of the Company’s business as currently conducted and as proposed to be conducted as described in the SEC Filings and for the ownership, maintenance and operation of the Company’s properties and assets, free and clear of all liens, encumbrances, adverse claims or, with respect to Intellectual Property owned by the Company, obligations to license such Intellectual Property, other than licenses of the Intellectual Property owned by the Company that are entered into in the ordinary course of the Company’s business. To the Company’s knowledge, the Company has a valid and enforceable right to use all third party Intellectual Property and Confidential Information used or held for use in the business of the Company.

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(d) To the Company’s knowledge, the conduct of the Company’s business as currently conducted or as proposed to be conducted as described in the SEC Filings, the use or exploitation of any Intellectual Property owned by the Company, or to its knowledge, the use or exploitation of any Intellectual Property licensed by the Company does not infringe, misappropriate or otherwise materially impair or conflict with (collectively, “Infringe”) any Intellectual Property rights of any third party and, to the Company’s knowledge, the Intellectual Property owned by the Company which is necessary for the conduct of Company’s business as currently conducted or as proposed to be conducted as set forth in the SEC Filings is not being Infringed by any third party. There is no litigation, court order, claim or assertion pending or outstanding or, to the Company’s knowledge, threatened, that seeks to limit or challenge the ownership, use, validity or enforceability of any Intellectual Property owned or licensed by the Company or the Company’s use of any Intellectual Property owned by a third party.

(e) To the Company’s knowledge, the consummation of the transactions contemplated hereby and by the other Transaction Documents will not result in the (i) loss, material impairment of or material restriction on any of the Intellectual Property or Confidential Information owned by the Company which is necessary for the conduct of Company’s business as currently conducted or as proposed to be conducted as set forth in the SEC Filings or (ii) material breach of any In-Bound License Agreement.

(f) The Company has taken reasonable steps to protect the Company’s rights in its Intellectual Property and Confidential Information. Each employee and consultant who has access to the Company’s Confidential Information necessary for the conduct of Company’s business as currently conducted has executed an agreement to maintain the confidentiality of such Confidential Information. To the Company’s knowledge, and except pursuant to non-disclosure agreements entered into between the Company and third parties in the ordinary course of business, there has been no disclosure of the Company’s Intellectual Property or Confidential Information to any third party. To the Company’s knowledge, there have been no misappropriations or infringements by any Person of any Intellectual Property used in the conduct or operation of the Company’s business.

4.16 Environmental Matters. The Company is not in violation of any statute, rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “Environmental Laws”). The Company does not own or operate any real property contaminated with any substance that is subject to any Environmental Laws, is not liable for any off-site disposal or contamination pursuant to any Environmental Laws, and is not subject to any claim relating to any Environmental Laws, which violation, contamination, liability or claim would reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect. There is no pending or, to the Company’s knowledge, threatened investigation that might lead to such a claim.

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4.17 Litigation. There are no pending or, to the Company’s knowledge, threatened actions, suits, proceedings, inquiries or investigations against or affecting the Company or any of its properties or any of the Company’s officers and directors in their capacities as such.

4.18 Financial Statements. The financial statements included in each SEC Filing present fairly, in all material respects, the financial position of the Company as of the dates shown and its results of operations and cash flows for the periods shown, and such financial statements have been prepared in conformity with United States generally accepted accounting principles applied on a consistent basis (“GAAP”) (except as may be disclosed therein or in the notes thereto, and, in the case of quarterly financial statements, as permitted by Form 10-Q under the Exchange Act). Except as set forth in the financial statements of the Company included in the SEC Filings filed prior to the date hereof, the Company has not incurred any liabilities, contingent or otherwise, except those incurred in the ordinary course of business, consistent with past practices since the date of such financial statements, none of which, individually or in the aggregate, would reasonably be expected to have a Material Adverse Effect.

4.19 Insurance Coverage. The Company maintains in full force and effect insurance coverage that is customary for comparably situated companies for the business being conducted and properties owned or leased by the Company.

4.20 Compliance with Nasdaq Continued Listing Requirements. The Company is in compliance with applicable Nasdaq continued listing requirements. The Company has not received any written notice with respect to the delisting of the Common Stock from the Nasdaq National Market.

4.21 Brokers and Finders. Other than Cowen & Co. LLC, the fees of which shall be paid by the Company, no Person will have, as a result of the transactions contemplated by the Transaction Documents, any valid right, interest or claim for any commission, fee or other compensation pursuant to any agreement, arrangement or understanding entered into by or on behalf of the Company.

4.22 No Directed Selling Efforts or General Solicitation. Neither the Company nor any Person acting on its behalf has conducted any general solicitation or general advertising (as those terms are used in Regulation D under the Securities Act) in connection with the offer or sale of the Securities.

4.23 No Integrated Offering. Neither the Company nor any Person acting on its behalf has, directly or indirectly, made any offers or sales of any Company security or solicited any offers to buy any security, under circumstances that would adversely affect reliance by the Company on Section 4(2) of the Securities Act for the exemption from registration for the transactions contemplated hereby or would require registration of the Securities under the Securities Act or would be integrated under the Nasdaq Marketplace Rules.

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4.24 Private Placement. Subject to the accuracy of each Investor’s representations in Section 5 hereof, the offer and sale of the Securities to the Investors as contemplated hereby is exempt from the registration requirements of the Securities Act.

4.25 Questionable Payments. Neither the Company nor, to the Company’s knowledge, any of its directors, officers, employees, agents or other Persons acting on behalf of the Company, has on behalf of the Company or in connection with its business: (a) used any corporate funds for unlawful contributions, gifts, entertainment or other unlawful expenses relating to political activity; (b) made any direct or indirect unlawful payments to any governmental officials or employees from corporate funds; (c) established or maintained any unlawful or unrecorded fund of corporate monies or other assets; (d) made any false or fictitious entries on the books and records of the Company; or (e) made any unlawful bribe, rebate, payoff, influence payment, kickback or other unlawful payment of any nature.

4.26 Transactions with Affiliates. None of the officers or directors of the Company and, to the Company’s knowledge, none of the employees of the Company is presently a party to any transaction with the Company (other than as holders of stock options and/or warrants, and for services as employees, officers and directors), including any contract, agreement or other arrangement providing for the furnishing of services to or by, providing for rental of real or Personal property to or from, or otherwise requiring payments to or from any officer, director or such employee or, to the Company’s knowledge, any entity in which any officer, director, or any such employee has a substantial interest or is an officer, director, trustee or partner.

4.27 Internal Controls. The Company is in material compliance with the provisions of the Sarbanes-Oxley Act of 2002 currently applicable to the Company. The Company maintains a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations, (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain asset accountability, (iii) access to assets is permitted only in accordance with management’s general or specific authorization, and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. The Company has established disclosure controls and procedures (as defined in Exchange Act Rules 13a-15 and 15d-15) for the Company and designed such disclosure controls and procedures to ensure that material information relating to the Company is made known to the certifying officers by others within those entities. The Company’s certifying officers have evaluated the effectiveness of the Company’s controls and procedures as of the end of the period covered by the most recently filed periodic report under the Exchange Act (such date, the “Evaluation Date”). The Company presented in its most recently filed periodic report under the Exchange Act the conclusions of the certifying officers about the effectiveness of the disclosure controls and procedures based on their evaluations as of the Evaluation Date. Since the Evaluation Date, there have been no significant changes in the Company’s internal controls (as such term is defined in Item 307(b) of Regulation S-K) or, to the Company’s knowledge, in other factors that could significantly affect the Company’s internal controls. The books, records and accounts of the Company accurately and fairly reflect, in all material respects, the transactions in, and dispositions of, the assets of,

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and the results of operations of, the Company. The Company maintains and will continue to maintain a standard system of accounting established and administered in accordance with GAAP and the applicable requirements of the Exchange Act.

4.28 Independent Accountants. Ernst & Young LLP is the Company’s independent registered public accounting firm as required by the Exchange Act, and the rules and regulations of the SEC thereunder.

4.29 Investment Company. The Company is not and, after giving effect to the offering and sale of the Securities, will not be an “investment company” within the meaning of the Investment Company Act of 1940, as amended.

4.30 Regulatory Compliance. The human clinical trials, animal studies and other preclinical tests conducted by the Company or in which the Company has participated or that are described in the SEC Filings or the results of which are referred to in the SEC Filings, and such studies and tests conducted on behalf of the Company or that the Company intends to rely on in support of regulatory approval by the United States Food and Drug Administration (the “FDA”) or foreign regulatory agencies, were and, if still pending, are being conducted in all material respects in accordance with experimental protocols, procedures and controls generally used by qualified experts in the preclinical or clinical study of new drugs; the descriptions of the results of such studies, test and trials contained in the SEC Filings are accurate and complete in all material respects, and, except as set forth in the SEC Filings, the Company has no knowledge of any other trials, studies or tests, the results of which the Company believes reasonably call into question the clinical trial results described or referred to in the SEC Filings when viewed in the context in which such results are described and the clinical state of development; and the Company has not received any notices or correspondence from the FDA or any other domestic or foreign governmental agency requiring the termination, suspension or material modification, other than modifications customarily implemented during the drug development process, of any preclinical tests or clinical trials conducted by or on behalf of the Company or in which the Company has participated that are described in the SEC Filings or the results of which are referred to in the SEC Filings.

4.31 Material Contracts. All material documents, contracts or other agreements of the Company required to be filed with the SEC have been filed with the SEC and are included in the exhibits to the SEC Filings. The description of the contracts, documents or other agreements contained in the SEC Filings (as the case may be) reflect in all material respects the terms of the underlying contract, document or other agreement. Each such contract, document or other agreement is in full force and effect and is valid and enforceable by and against the Company in accordance with its terms. The Company is not in default in the observance or performance of any term or obligation to be performed by it under any such agreement, and no event has occurred which with notice or lapse of time or both would constitute such a default, in any such case which default or event, individually or in the aggregate, would result in a Material Adverse Effect.

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5. Representations and Warranties of the Investors. Each of the Investors hereby, severally and not jointly, represents and warrants to the Company that:

5.1 Organization and Existence. Such Investor is a validly existing corporation, limited partnership or limited liability company and has all requisite corporate, partnership or limited liability company power and authority to invest in the Securities pursuant to this Agreement.

5.2 Authorization. The execution, delivery and performance by such Investor of the Transaction Documents have been duly authorized, and the Transaction Documents constitute the valid and legally binding obligations of such Investor, enforceable against such Investor in accordance with their respective terms, subject to bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability, relating to or affecting creditors’ rights generally.

5.3 Purchase Entirely for Own Account. The Securities to be received by such Investor hereunder will be acquired for such Investor’s own account, not as nominee or agent, and not with a view to the resale or distribution of any part thereof in violation of the Securities Act, and such Investor has no present intention of selling, granting any participation in, or otherwise distributing the same in violation of the Securities Act. Such Investor is not a broker-dealer registered with the SEC under the Exchange Act or an entity engaged in a business that would require it to be so registered.

5.4 Investment Experience. Such Investor acknowledges that it can bear the economic risk and complete loss of its investment in the Securities and has such knowledge and experience in financial or business matters that it is capable of evaluating the merits and risks of the investment in the Securities contemplated hereby.

5.5 Disclosure of Information. Such Investor has had an opportunity to receive all information related to the Company requested by it and to ask questions of and receive answers from the Company regarding the Company, its business and the terms and conditions of the offering of the Securities. Such Investor acknowledges receipt of copies of the SEC Filings.

5.6 Restricted Securities. Such Investor understands that the Securities are characterized as “restricted securities” under the U.S. federal securities laws inasmuch as they are being acquired from the Company in a transaction not involving a public offering and that under such laws and applicable regulations such securities may be resold without registration under the Securities Act only in certain limited circumstances.

5.7 Legends. It is understood that, except as provided below, certificates evidencing the Securities may bear the following or any similar legend:

(a) “The securities represented hereby have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), or any state securities laws. The securities represented hereby may not be transferred unless (i) such securities have been registered for sale pursuant to the Securities Act, (ii) such securities may be sold pursuant to Rule 144(k), or (iii) the Company has received an opinion of counsel reasonably satisfactory to it

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that such transfer may lawfully be made without registration under the Securities Act or qualification under applicable state securities laws.”

(b) If required by the authorities of any state in connection with the issuance of sale of the Securities, the legend required by such state authority.

5.8 Accredited Investor. Such Investor is an accredited investor as defined in Rule 501(a) of Regulation D, as amended, under the Securities Act.

5.9 No General Solicitation. Such Investor did not learn of the investment in the Securities as a result of any public advertising or general solicitation.

5.10 Brokers and Finders. No Person will have, as a result of the transactions contemplated by the Transaction Documents, any valid right, interest or claim against or upon the Company or an Investor for any commission, fee or other compensation pursuant to any agreement, arrangement or understanding entered into by or on behalf of such Investor.

5.11 Prohibited Transactions. During the last thirty (30) days prior to the date hereof, neither such Investor nor any Affiliate of such Investor which (x) had knowledge of the transactions contemplated hereby, (y) has or shares discretion relating to such Investor’s investments or trading or information concerning such Investor’s investments, including in respect of the Securities, or (z) is subject to such Investor’s review or input concerning such Affiliate’s investments or trading (collectively, “Trading Affiliates”) has, directly or indirectly, (a) acquired, agreed to acquired (other than pursuant to this Agreement), offered for sale, sold, pledged or otherwise disposed of any Common Stock, (b) effected or agreed to effect any short sale, whether or not against the box, established any “put equivalent position” (as defined in Rule 16a-1(h) under the Exchange Act) with respect to the Common Stock, granted any other right (including, without limitation, any put or call option) with respect to the Common Stock or with respect to any security that includes, relates to or derived any significant part of its value from the Common Stock or otherwise sought to hedge its position in the Shares or (c) entered into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic benefits or risks of ownership of any securities of the Company, whether any such transaction described in clauses (a), (b) or (c) was or is to be settled by delivery of securities of the Company, other securities, cash or otherwise (each, a “Prohibited Transaction”). Prior to the earliest to occur of (i) the termination of this Agreement, (ii) the Effective Date or (iii) the Effectiveness Deadline, such Investor shall not, and shall cause its Trading Affiliates not to, engage, directly or indirectly, in a Prohibited Transaction. Such Investor acknowledges that the representations, warranties and covenants contained in this Section 5.11 are being made for the benefit of the Investors as well as the Company and that each of the other Investors shall have an independent right to assert any claims against such Investor arising out of any breach or violation of the provisions of this Section 5.11.

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6. Conditions to Closing.

6.1 Conditions to the Investors’ Obligations. The obligation of each Investor to purchase the Shares and the Warrants at the Closing is subject to the satisfaction, on or prior to the Closing Date, of the following conditions, any of which may be waived by such Investor (as to itself only):

(a) The representations and warranties made by the Company in Section 4 hereof qualified as to materiality shall be true and correct on the date hereof and on the Closing Date (except to the extent any such representation or warranty expressly speaks as of a specific date, in which case such representation or warranty shall be true and correct as of such date), and the representations and warranties made by the Company in Section 4 hereof not qualified as to materiality shall be true and correct in all material respects on the date hereof and on the Closing Date (except to the extent any such representation or warranty expressly speaks as of a specific date, in which case such representation or warranty shall be true and correct in all material respects as of such specific date). The Company shall have performed in all material respects all obligations and covenants herein required to be performed by it on or prior to the Closing Date. The Company shall have delivered a certificate, executed on behalf of the Company by its Chief Executive Officer or its Chief Financial Officer, dated as of the Closing Date, certifying to the fulfillment of the condition specified in this Section 6.1(a).

(b) The Company shall have obtained any and all consents, permits, approvals, registrations and waivers necessary or appropriate for consummation of the purchase and sale of the Securities and the consummation of the other transactions contemplated by the Transaction Documents to be consummated on or prior to the Closing Date, all of which shall be in full force and effect.

(c) The Company shall have executed and delivered the Transaction Documents.

(d) No judgment, writ, order, injunction, award or decree of or by any court, or judge, justice or magistrate, including any bankruptcy court or judge, or any order of or by any governmental authority, shall have been issued, and no action or proceeding shall have been instituted by any governmental authority, enjoining or preventing the consummation of the transactions contemplated by the Transaction Documents.

(e) The Company shall have delivered a certificate, executed on behalf of the Company by its Secretary, dated as of the Closing Date, certifying the resolutions adopted by the Board of Directors of the Company approving the transactions contemplated by the Transaction Documents, certifying the current versions of the Certificate of Incorporation and Bylaws of the Company and certifying as to the signatures and authority of Persons signing the Transaction Documents and related documents on behalf of the Company.

(f) The Investors shall have received an opinion from Latham & Watkins LLP, the Company’s counsel, dated as of the Closing Date, in the form attached hereto as Exhibit D.

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(g) No stop order or suspension of trading shall have been imposed by Nasdaq, the SEC or any other governmental or regulatory body with respect to public trading in the Common Stock. The Company shall not have received notice of any delisting on Nasdaq or that it is violation of any Nasdaq rule, regulation or interpretation which could lead to delisting.

(h) The aggregate purchase price for the Shares and the Warrants shall be at least $40,000,000, of which at least $17,000,000 and not more than $20,000,000 of the aggregate purchase price shall represent investment by Alta BioPharma Partners III, L.P., Alta BioPharma Partners III GmbH & Co. Beteiligungs KG and Alta Embarcadero BioPharma Partners III, LLC (collectively, “Alta BioPharma Partners”) and Persons that are (i) stockholders of the Company as of the date hereof and (ii) affiliated with members of the board of directors.

(i) The Company’s delivery (i) to its transfer agent of irrevocable instructions to issue and deliver to each Investor (or in such nominee name(s) as designated by such Investor in writing) certificates evidencing such number of Shares as set forth on the signature pages to this Agreement, and (ii) duly executed copies of the Warrants to the Investor.

(j) The Company’s delivery to the Investors of an executed Lockup Agreement from Venrock Associates, Warburg Pincus and each of the Company’s directors and executive officers.

(k) The Nondisclosure Agreement dated as of January 25, 2006 between Alta BioPharma Partners and the Company shall be amended or terminated, as mutually agreeable to Alta BioPharma Partners and the Company, to permit the transactions contemplated by this Agreement.

6.2 Conditions to Obligations of the Company. The Company’s obligation to sell and issue the Shares and the Warrants at the Closing is subject to the satisfaction on or prior to the Closing Date of the following conditions, any of which may be waived by the Company:

(a) The representations and warranties made by the Investors in Section 5 hereof shall be true and correct in all material respects when made and as of the Closing Date with the same force and effect as if they had been made on and as of said date (except to the extent any such representation or warranty expressly speaks as of a specific date, in which case such representation or warranty shall be true and correct in all material respects as of such specific date).

(b) The Investors shall have executed and delivered this Agreement and the Registration Rights Agreement.

(c) No judgment, writ, order, injunction, award or decree of or by any court, or judge, justice or magistrate, including any bankruptcy court or judge, or any order of or by any governmental authority, shall have been issued, and no action or proceeding shall have been instituted by any governmental authority, enjoining or preventing the consummation of the transactions contemplated by the Transaction Documents.

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(d) The Investors shall have delivered the Purchase Price for the Shares and the Warrants to the Company.

6.3 Termination of Obligations to Effect Closing; Effects. The obligation of the Company, on the one hand, and the Investors, on the other hand, to effect the Closing shall terminate as follows:

(a) Upon the mutual written consent of the Company and the Investors;

(b) By the Company if any of the conditions set forth in Section 6.2 shall have become incapable of fulfillment, and shall not have been waived by the Company;

(c) By an Investor (with respect to itself only) if any of the conditions set forth in Section 6.1 shall have become incapable of fulfillment, and shall not have been waived by the Investor; or

(d) By either the Company or any Investor (with respect to itself only) if the Closing has not occurred on or prior to April 30, 2006;

provided, however, that, except in the case of clause (i) above, the party seeking to terminate its obligation to effect the Closing shall not then be in breach of any of its representations, warranties, covenants or agreements contained in this Agreement if such breach has resulted in the circumstances giving rise to such party’s seeking to terminate its obligation to effect the Closing.

7. Covenants and Agreements.

7.1 No Conflicting Agreements. The Company will not take any action, enter into any agreement or make any commitment that would conflict or interfere in any material respect with the Company’s obligations to the Investors under the Transaction Documents.

7.2 Insurance. The Company shall not materially reduce the insurance coverages described in Section 4.19.

7.3 Compliance with Laws. The Company will comply in all material respects with all applicable laws, rules, regulations, orders and decrees of all governmental authorities.

7.4 Listing of Underlying Shares and Related Matters. Promptly following the date hereof, the Company shall take all necessary action to cause the Shares and the Warrant Shares to be listed on the Nasdaq National Market. The Company will use commercially reasonable efforts to continue the listing and trading of its Common Stock on the Nasdaq National Market and, in accordance, therewith, will use commercially reasonable efforts to comply in all respects with the Company’s reporting, filing and other obligations under the bylaws or rules of such market or exchange, as applicable.

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7.5 Termination of Covenants. The provisions of Sections 7.1 through 7.4 shall terminate and be of no further force and effect on the date on which the Company’s obligations under the Registration Rights Agreement to register or maintain the effectiveness of any registration covering the Registrable Securities (as such term is defined in the Registration Rights Agreement) shall terminate.

7.6 Removal of Legends. Upon the earlier of (i) the sale pursuant to the Registration Statement and receipt by the Company or its agents of the Investor’s written confirmation that such Shares or the Warrant Shares were disposed of in compliance with the prospectus delivery requirements of the Securities Act or (ii) Rule 144(k) under the Securities Act becoming available for the resale of the Investor’s Shares or the Warrant Shares, the Company shall within three (3) Business Days of an Investor’s written request, cause certificates evidencing the Investor’s Shares or Warrant Shares to be replaced with certificates which do not bear such restrictive legends.

7.7 Release From Lockup Agreement. Without the prior written consent of Alta BioPharma Partners, the Company shall not release any Person from his, her or its respective obligations under any Lockup Agreement.

8. Survival and Indemnification.

8.1 Survival. The representations, warranties, covenants and agreements contained in this Agreement shall survive the Closing of the transactions contemplated by this Agreement for a period of two years, except as otherwise expressly provided in this Agreement.

8.2 Indemnification. The Company agrees to indemnify and hold harmless each Investor and its Affiliates and their respective directors, officers, employees and agents and each person who controls an Investor within the meaning of the Securities Act from and against any and all losses, claims, damages, liabilities and expenses (including without limitation reasonable attorneys’ fees and disbursements and other expenses incurred in connection with investigating, preparing or defending any action, claim or proceeding, pending or threatened and the costs of enforcement thereof) (collectively, “Losses”) to which such Person may become subject as a result of any breach of representation, warranty, covenant or agreement made by or to be performed on the part of the Company under the Transaction Documents. Each Investor agrees, severally and not jointly, to indemnify and hold harmless the Company and its directors, officers, employees and agents from and against any and all Losses to which such Person may become subject as a result of any breach of representation, warranty, covenant or agreement made by or to be performed on the part of such Investor under the Transaction Documents.

8.3 Conduct of Indemnification Proceedings. Any Person entitled to indemnification hereunder shall (i) give prompt notice to the indemnifying party of any claim with respect to which it seeks indemnification and (ii) permit such indemnifying party to assume the defense of such claim with counsel reasonably satisfactory to the indemnified party; provided that any Person entitled to indemnification hereunder shall have the right to employ separate

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counsel and to participate in the defense of such claim, but the fees and expenses of such counsel shall be at the expense of such Person unless (a) the indemnifying party has agreed to pay such fees or expenses, or (b) the indemnifying party shall have failed to assume the defense of such claim within five (5) Business Days after written notice thereof and employ counsel reasonably satisfactory to such Person or (c) in the reasonable judgment of any such Person, considering the advice of counsel, a conflict of interest exists between such Person and the indemnifying party with respect to such claims (in which case, if the Person notifies the indemnifying party in writing that such Person elects to employ separate counsel at the expense of the indemnifying party, the indemnifying party shall not have the right to assume the defense of such claim on behalf of such Person); and provided, further, that the failure of any indemnified party to give notice as provided herein shall not relieve the indemnifying party of its obligations hereunder, except to the extent that such failure to give notice shall materially adversely affect the indemnifying party in the defense of any such claim or litigation, but the omission so to deliver notice to the indemnifying party will not relieve it of any liability that it may have to any indemnified party otherwise than under this Section 8. It is understood that the indemnifying party shall not, in connection with any proceeding in the same jurisdiction, be liable for fees or expenses of more than one additional firm of attorneys at any time for all such indemnified parties. No indemnifying party will, except with the consent of the indemnified party, consent to entry of any judgment or enter into any settlement that does not include as an unconditional term thereof the giving by the claimant or plaintiff to such indemnified party of a release from all liability in respect of such claim or litigation.

9. Miscellaneous.

9.1 Successors and Assigns. This Agreement may not be assigned by a party hereto without the prior written consent of the Company or the Investors, as applicable, provided, however, that an Investor may assign its rights and delegate its duties hereunder in whole or in part to an Affiliate acquiring some or all of its Shares or Warrant Shares after notice duly given by such Investor to the Company, provided that no such assignment or obligation shall affect the obligations of such Investor hereunder. The provisions of this Agreement shall inure to the benefit of and be binding upon the respective permitted successors and assigns of the parties. Nothing in this Agreement, express or implied, is intended to confer upon any party other than the parties hereto or their respective successors and assigns any rights, remedies, obligations, or liabilities under or by reason of this Agreement, except as expressly provided in this Agreement.

9.2 Counterparts; Faxes. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. This Agreement may also be executed via facsimile, which shall be deemed an original.

9.3 Titles and Subtitles. The titles and subtitles used in this Agreement are used for convenience only and are not to be considered in construing or interpreting this Agreement.

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9.4 Notices. Unless otherwise provided, any notice required or permitted under this Agreement shall be given in writing and shall be deemed effectively given as hereinafter described (i) if given by Personal delivery, then such notice shall be deemed given upon such delivery, (ii) if given by telex or telecopier, then such notice shall be deemed given upon receipt of confirmation of complete transmittal, (iii) if given by mail, then such notice shall be deemed given upon the earlier of (A) receipt of such notice by the recipient or (B) three days after such notice is deposited in first class mail, postage prepaid, and (iv) if given by an internationally recognized overnight air courier, then such notice shall be deemed given one Business Day after delivery to such carrier. All notices shall be addressed to the party to be notified at the address as follows, or at such other address as such party may designate by ten days’ advance written notice to the other party:

If to the Company:

Sunesis Pharmaceuticals, Inc.

341 Oyster Point Boulevard

South San Francisco, California 94080

Attention: General Counsel

Fax: (650) 266-3505

With a copy to:

Latham & Watkins LLP

135 Commonwealth Drive

Menlo Park, California 94025

Attention:   Alan Mendelson

                    William Davisson

Fax: (650) 463-2600

If to the Investors, to the addresses set forth on the signature pages hereto.

9.5 Expenses. The parties hereto shall pay their own costs and expenses in connection herewith, provided that the Company shall pay the reasonable fees and expenses, not to exceed $50,000 in the aggregate, of Cooley Godward LLP as counsel to Alta BioPharma Partners. In the event that legal proceedings are commenced by any party to this Agreement against another party to this Agreement in connection with this Agreement or the other Transaction Documents, the party or parties which do not prevail in such proceedings shall severally, but not jointly, pay their pro rata share of the reasonable attorneys’ fees and other reasonable out-of-pocket costs and expenses incurred by the prevailing party in such proceedings.

9.6 Amendments and Waivers. Any term of this Agreement may be amended and the observance of any term of this Agreement may be waived (either generally or in a particular instance and either retroactively or prospectively), only with the written consent of the Company and the Investors. Any amendment or waiver effected in accordance with this

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paragraph shall be binding upon each holder of any Securities purchased under this Agreement at the time outstanding, each future holder of all such Securities, and the Company.

9.7 Publicity. Except as set forth below, no public release or announcement concerning the transactions contemplated hereby shall be issued by the Company or the Investors without the prior consent of the Company (in the case of a release or announcement by the Investors) or the Investors (in the case of a release or announcement by the Company) (which consents shall not be unreasonably withheld), except as such release or announcement may be required by law or the applicable rules or regulations of Nasdaq, any securities exchange or other securities market. On the trading day immediately following the date hereof, the Company shall issue a press release disclosing the transactions contemplated by this Agreement. No later than the fourth trading day following the date hereof, the Company will file a Current Report on Form 8-K describing the Transaction Documents and attaching the press release described in the foregoing sentence. In addition, the Company will make such other filings (including filing the Transaction Documents with the SEC) and notices in the manner and time required by the SEC or Nasdaq.

9.8 Severability. Any provision of this Agreement that is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof but shall be interpreted as if it were written so as to be enforceable to the maximum extent permitted by applicable law, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction. To the extent permitted by applicable law, the parties hereby waive any provision of law which renders any provision hereof prohibited or unenforceable in any respect.

9.9 Entire Agreement. This Agreement, including the exhibits and the Disclosure Schedules, and the other Transaction Documents constitute the entire agreement among the parties hereof with respect to the subject matter hereof and thereof and supersede all prior agreements and understandings, both oral and written, between the parties with respect to the subject matter hereof and thereof.

9.10 Further Assurances. The parties shall execute and deliver all such further instruments and documents and take all such other actions as may reasonably be required to carry out the transactions contemplated hereby and to evidence the fulfillment of the agreements herein contained.

9.11 Governing Law; Consent to Jurisdiction; Waiver of Jury Trial. This Agreement shall be governed by, and construed in accordance with, the internal laws of the State of California without regard to the choice of law principles thereof. Each of the parties hereto irrevocably submits to the exclusive jurisdiction of the courts of the State of California located in San Mateo County and the United States District Court for the Northern District of California for the purpose of any suit, action, proceeding or judgment relating to or arising out of this Agreement and the transactions contemplated hereby. Service of process in connection with any such suit, action or proceeding may be served on each party hereto anywhere in the world by the same methods as are specified for the giving of notices under this Agreement. Each of the

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parties hereto irrevocably consents to the jurisdiction of any such court in any such suit, action or proceeding and to the laying of venue in such court. Each party hereto irrevocably waives any objection to the laying of venue of any such suit, action or proceeding brought in such courts and irrevocably waives any claim that any such suit, action or proceeding brought in any such court has been brought in an inconvenient forum. EACH OF THE PARTIES HERETO WAIVES ANY RIGHT TO REQUEST A TRIAL BY JURY IN ANY LITIGATION WITH RESPECT TO THIS AGREEMENT AND REPRESENTS THAT COUNSEL HAS BEEN CONSULTED SPECIFICALLY AS TO THIS WAIVER.

9.12 Independent Nature of Investors’ Obligations and Rights. The obligations of each Investor under any Transaction Document are several and not joint with the obligations of any other Investor, and no Investor shall be responsible in any way for the performance of the obligations of any other Investor under any Transaction Document. The decision of each Investor to purchase Securities pursuant to the Transaction Documents has been made by such Investor independently of any other Investor. Nothing contained herein or in any Transaction Document, and no action taken by any Investor pursuant thereto, shall be deemed to constitute the Investors as a partnership, an association, a joint venture or any other kind of entity, or create a presumption that the Investors are in any way acting in concert or as a group with respect to such obligations or the transactions contemplated by the Transaction Documents. Each Investor acknowledges that no other Investor has acted as agent for such Investor in connection with making its investment hereunder and that no Investor will be acting as agent of such Investor in connection with monitoring its investment in the Securities or enforcing its rights under the Transaction Documents. Each Investor shall be entitled to independently protect and enforce its rights, including, without limitation, the rights arising out of this Agreement or out of the other Transaction Documents, and it shall not be necessary for any other Investor to be joined as an additional party in any proceeding for such purpose. The Company acknowledges that each of the Investors has been provided with the same Transaction Documents for the purpose of closing a transaction with multiple Investors and not because it was required or requested to do so by any Investor.

(Signature page follows)

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IN WITNESS WHEREOF, the parties have executed this Common Stock Purchase Agreement as of the date first above written.

The Company:	SUNESIS PHARMACEUTICALS, INC.
	By:	/s/ Daniel N. Swisher, Jr.
	Name:	Daniel N. Swisher, Jr.
	Title:	President and Chief Executive Officer

The Investors:	ABINGWORTH BIOEQUITIES MASTER FUND LTD.
	BY:     Its Manager, Abingworth Management
	By:	/s/ James Abell
	Name:	James Abell
	Title:	Director

Purchase Price: $2,917,513.82

Number of Shares: 466,989

Number of shares of Common

    Stock underlying Warrant: 140,097

Address for Notice:

Abingworth Bioequities Master Fund Ltd.

c/o Bisys Hedge Fund Services (Ireland) LTD

Attention: Glenn Kennedy

One Georges Quay Plaza, 6th Floor

Dublin 2, Ireland

The Investors:	ALTA BIOPHARMA PARTNERS III, L.P.
	BY:     ALTA BIOPHARMA MANAGEMENT III, LLC
	By:	/s/ Hilary Strain
	Name:	Hilary Strain
	Title:	Vice President, Finance and Administration

Purchase Price: $11,057,918.75

Number of Shares: 1,769,975

Number of shares of Common

    Stock underlying Warrant: 530,992

Address for Notice:

Alta BioPharma Partners III, L.P.

Attention: Elaine Penny

One Embarcadero Center, 37th Floor

San Francisco, CA 94111

TAX ID NUMBER:

The Investors:	Alta BioPharma Partners III GmbH & Co. Beteiligungs KG
	BY:     ALTA BIOPHARMA MANAGEMENT III, LLC
	By:	/s/ Hilary Strain
	Name:	Hilary Strain
	Title:	Vice President, Finance and Administration

Purchase Price: $742,640.33

Number of Shares: 118,870

Number of shares of Common

    Stock underlying Warrant: 35,661

Address for Notice:

Alta BioPharma Partners III GmbH & Co.

Beteiligungs KG

Attention: Elaine Penny

One Embarcadero Center, 37th Floor

San Francisco, CA 94111

TAX ID NUMBER:

The Investors:	ALTA EMBARCADERO BIOPHARMA PARTNERS III, LLC
	By:	/s/ Hilary Strain
	Name:	Hilary Strain
	Title:	Vice President, Finance and Administration

Purchase Price: $272,509.74

Number of Shares: 43,619

Number of shares of Common

    Stock underlying Warrant: 13,086

Address for Notice:

Alta Embarcadero BioPharma Partners III, LLC

Attention: Elaine Penny

One Embarcadero Center, 37th Floor

San Francisco, CA 94111

TAX ID NUMBER:

The Investors:	BIOTECHNOLOGY VALUE FUND, L.P.
	By:	/s/ Mark Lambert
	Name:	Mark Lambert
	Title:	President of BVF Inc.
		General Partner of BVF Partners L.P.
		General Partner of Biotechnology Value Fund, L.P.

Purchase Price: $654,319.43

Number of Shares: 104,733

Number of shares of Common

    Stock underlying Warrant: 31,420

Address for Notice:

Biotechnology Value Fund, L.P.

Attention: Elizabeth Delaney

900 N. Michigan Avenue

Suite 1100

Chicago, IL 60611

The Investors:	BIOTECHNOLOGY VALUE FUND II, L.P.
	By:	/s/ Mark Lambert
	Name:	Mark Lambert
	Title:	President of BVF Inc.
		General Partner of BVF Partners L.P.
		General Partner of Biotechnology Value Fund, L.P.

Purchase Price: $449,195.25

Number of Shares: 71,900

Number of shares of Common

    Stock underlying Warrant: 21,570

Address for Notice:

Biotechnology Value Fund II, L.P.

Attention: Elizabeth Delaney

900 N. Michigan Avenue

Suite 1100

Chicago, IL 60611

The Investors:	INVESTMENT 10, L.L.C.
	By:	/s/ Mark Lambert
	Name:	Mark Lambert
	Title:	President of BVF Inc.
		General Partner of BVF Partners L.P.
		General Partner of Biotechnology Value Fund, L.P.

Purchase Price: $190,042.74

Number of Shares: 30,419

Number of shares of Common

    Stock underlying Warrant: 9,126

Address for Notice:

Investment 10, L.L.C.

Attention: Elizabeth Delaney

900 N. Michigan Avenue

Suite 1100

Chicago, IL 60611

The Investors:	BVF INVESTMENTS, L.L.C.
	By:	/s/ Mark Lambert
	Name:	Mark Lambert
	Title:	President of BVF Inc.
		General Partner of BVF Partners L.P.
		General Partner of Biotechnology Value Fund, L.P.

Purchase Price: $1,724,559.90

Number of Shares: 276,040

Number of shares of Common

    Stock underlying Warrant: 82,812

Address for Notice:

BVF Investments, L.L.C.

Attention: Elizabeth Delaney

900 N. Michigan Avenue

Suite 1100

Chicago, IL 60611

The Investors:	DOMAIN PUBLIC EQUITY PARTNERS, L.P.
	BY: Domain Public Equity Associates, L.L.C.
	By:	/s/ Nicole Vitullo
	Name:	Nicole Vitullo
	Title:	Managing Member

Purchase Price: $5,030,193.38

Number of Shares: 805,153

Number of shares of Common

    Stock underlying Warrant: 241,546

Address for Notice:

Domain Public Equity Partners, L.P.

c/o Domain Associates

One Palmer Sq. Suite 515

Princeton, NJ 08542

The Investors:	THE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIVERSITY (SBST)
	By:	/s/ Martina S. Poquet
	Name:	Martina S. Poquet
	Title:	Director, Separate Investments Division

Purchase Price: $99,997.51

Number of Shares: 16,006

Number of shares of Common

    Stock underlying Warrant: 4,802

Address for Notice:

The Board of Trustees of the Leland Stanford Junior

University (SBST)

c/o Stanford Management Company

Attention: Martina Poquet

2770 Sand Hill Road

Menlo Park, CA 94025

The Investors:	Warburg, Pincus Equity Partners, L.P.
	By:	Warburg Pincus Partners, LLC,
		its General Partner
	By:	Warburg, Pincus & Co.,
		its Managing Member
	By:	/s/ Jonathan Leff
	Name:	Jonathan Leff
	Title:	Partner

Purchase Price: $4,753,535.32

Number of Shares: 760,870

Number of shares of Common

    Stock underlying Warrant: 228,261

Address for Notice:

Warburg, Pincus Equity Partners, L.P.

Attention: Jonathan Leff

466 Lexington Avenue

New York, NY 10017

TAX ID NUMBER:

The Investors:	Warburg, Pincus Netherlands Equity Partners I, C.V.
	By:	Warburg Pincus Partners, LLC,
		its General Partner
	By:	Warburg, Pincus & Co.,
		its Managing Member
	By:	/s/ Jonathan Leff
	Name:	Jonathan Leff
	Title:	Partner

Purchase Price: $251,505.60

Number of Shares: 40,257

Number of shares of Common

    Stock underlying Warrant: 12,077

Address for Notice:

Warburg, Pincus Netherlands Equity Partners I, C.V. Attention: Jonathan Leff

466 Lexington Avenue

New York, NY 10017

TAX ID NUMBER:

The Investors:	Warburg, Pincus Netherlands Equity Partners III, C.V.
	By:	Warburg Pincus Partners, LLC,
		its General Partner
	By:	Warburg, Pincus & Co.,
		its Managing Member
	By:	/s/ Jonathan Leff
	Name:	Jonathan Leff
	Title:	Partner

Purchase Price: $25,152.46

Number of Shares: 4,026

Number of shares of Common

    Stock underlying Warrant: 1,208

Address for Notice:

Warburg, Pincus Netherlands Equity Partners III, C.V.

Attention: Jonathan Leff

466 Lexington Avenue

New York, NY 10017

TAX ID NUMBER:

The Investors:	Deerfield Special Situations Fund International, Ltd.
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO

Purchase Price: $3,498,475.00

Number of Shares: 560,000

Number of shares of Common

    Stock underlying Warrant: 167,000

Address for Notice:

Deerfield Special Situations Fund International, Ltd.

Attention: Darren Levine

780 Third Avenue - 37th Floor

New York, NY 10017

The Investors:	Deerfield Special Situations Fund, L.P.
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO

Purchase Price: $1,886,670.00

Number of Shares: 302,000

Number of shares of Common

    Stock underlying Warrant: 90,000

Address for Notice:

Deerfield Special Situations Fund, Ltd.

Attention: Darren Levine

780 Third Avenue - 37th Floor

New York, NY 10017

The Investors:	Deerfield Partners, L.P.
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO

Purchase Price: $2,020,116.76

Number of Shares: 323,306

Number of shares of Common

    Stock underlying Warrant: 99,092

Address for Notice:

Deerfield Partners, L.P.

Attention: Darren Levine

780 Third Avenue - 37th Floor

New York, NY 10017

The Investors:	Deerfield International Limited
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO

Purchase Price: $2,655,125.00

Number of Shares: 425,000

Number of shares of Common

    Stock underlying Warrant: 127,000

Address for Notice:

Deerfield International Limited

Attention: Darren Levine

780 Third Avenue - 37th Floor

New York, NY 10017

The Investors:	Baker Bros. Investments, L.P.
	BY: Baker Bros. Capital, L.P. (general partner)
	BY: Baker Bros. Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $214,807.81

Number of Shares: 34,383

Number of shares of Common

    Stock underlying Warrant: 10,315

Address for Notice:

Baker Bros. Investments, L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

The Investors:	Baker Bros. Investments II, L.P.
	BY: Baker Bros. Capital, L.P. (general partner)
	BY: Baker Bros. Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $190,705.00

Number of Shares: 30,525

Number of shares of Common

    Stock underlying Warrant: 9,158

Address for Notice:

Baker Bros. Investments II, L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

The Investors:	Baker Biotech Fund I, L.P.
	BY: Baker Bros. Capital, L.P. (general partner)
	BY: Baker Bros. Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $2,129,297.91

Number of Shares: 340,824

Number of shares of Common

    Stock underlying Warrant: 102,247

Address for Notice:

Baker Biotech Fund I, L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

The Investors:	Baker Biotech Fund II, L.P.
	BY: Baker Bros. Capital II, L.P. (general partner)
	BY: Baker Bros. Capital II (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $1,940,942.13

Number of Shares: 310,675

Number of shares of Common

    Stock underlying Warrant: 93,203

Address for Notice:

Baker Biotech Fund II, L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

The Investors:	Baker Biotech Fund II (Z), L.P.
	BY: Baker Bros. Capital II (Z), L.P. (general partner)
	BY: Baker Bros. Capital II (Z) (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $253,504.80

Number of Shares: 40,577

Number of shares of Common

    Stock underlying Warrant: 12,173

Address for Notice:

Baker Biotech Fund II (Z), L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

The Investors:	Baker Biotech Fund III, L.P.
	BY: Baker Bros. Capital III, L.P. (general partner)
	BY: Baker Bros. Capital III (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $1,876,742.79

Number of Shares: 300,399

Number of shares of Common

    Stock underlying Warrant: 90,120

Address for Notice:

Baker Biotech Fund III, L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

The Investors:	Baker Biotech Fund III (Z), L.P.
	BY: Baker Bros. Capital III (Z), L.P. (general partner)
	BY: Baker Bros. Capital III (Z) (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $306,771.00

Number of Shares: 49,103

Number of shares of Common

    Stock underlying Warrant: 14,731

Address for Notice:

Baker Biotech Fund III (Z), L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

The Investors:	14159, L.P.
	BY: 14159 Capital, L.P. (general partner)
	BY: 14159 Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

Purchase Price: $129,498.00

Number of Shares: 20,728

Number of shares of Common

    Stock underlying Warrant: 6,217

Address for Notice:

14159, L.P.

Attention: Julian Baker

667 Madison Avenue, 17th Floor

New York, NY 10021

EX-99.D

Exhibit D-1

THIS WARRANT AND THE UNDERLYING SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. THIS WARRANT AND THE UNDERLYING SECURITIES MAY NOT BE TRANSFERRED UNLESS (I) THIS WARRANT AND THE UNDERLYING SECURITIES HAVE BEEN REGISTERED FOR SALE PURSUANT TO THE SECURITIES ACT, (II) THIS WARRANT AND THE UNDERLYING SECURITIES MAY BE SOLD PURSUANT TO RULE 144(K) OR (III) THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO IT THAT SUCH TRANSFER MAY LAWFULLY BE MADE WITHOUT REGISTRATION UNDER THE SECURITIES ACT OR QUALIFICATION UNDER APPLICABLE STATE SECURITIES LAWS.

WARRANT TO PURCHASE SHARES OF COMMON STOCK

OF SUNESIS PHARMACEUTICALS, INC.

THIS CERTIFIES THAT, for value received, Warburg, Pincus Equity Partners, L.P. is entitled to subscribe for and purchase 228,261 fully paid and nonassessable shares (the “Shares”) of common stock, par value $0.0001 per share (the “Common Stock”), of Sunesis Pharmaceuticals, Inc., a Delaware corporation (the “Company”), at a price per share equal to $6.21 (such price and such other price as shall result, from time to time, from the adjustments specified in Section 4 hereof is herein referred to as the “Warrant Price”), upon the terms and subject to the conditions hereinafter set forth.

1. Term. The purchase right represented by this warrant is exercisable, in whole or in part, at any time and from time to time from March 17, 2006 (the “Date of Grant”) until the 7-year anniversary of the Date of Grant.

2. Method of Exercise; Payment; Issuance of New Warrant. Subject to Section 1 hereof, the purchase right represented by this warrant may be exercised by the holder hereof, in whole or in part and from time to time, at the election of the holder hereof, by (a) the surrender of this warrant (with the notice of exercise substantially in the form attached hereto as Exhibit A-1 duly completed and executed) at the principal office of the Company and by the payment to the Company, by certified or bank check, or by wire transfer to an account designated by the Company (a “Wire Transfer”) of an amount equal to the then applicable Warrant Price multiplied by the number of Shares then being purchased; or (b) exercise of the “net issuance” right provided for in Section 9 hereof. The person or persons in whose name(s) any certificate(s) representing shares of Common Stock shall be issuable upon exercise of this warrant shall be deemed to have become the holder(s) of record of, and shall be treated for all purposes as the record holder(s) of, the shares represented thereby (and such shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this warrant is exercised. In the event of any exercise of the rights represented by this warrant, certificates for the shares of stock so purchased shall be delivered to the holder hereof as soon as practicable and in any event within thirty (30) days after such exercise and, unless this warrant has been fully exercised or expired, a new warrant representing the portion of the Shares, if any, with respect to which this warrant shall not then have been exercised shall also be issued to the holder hereof as soon as practicable and in any event within such thirty-day period;

provided, however, if requested by the holder of this warrant, the Company shall use reasonable efforts to cause its transfer agent to deliver the certificate representing Shares issued upon exercise of this warrant to a broker or other person (as directed by the holder exercising this warrant) within the time period required to settle any trade made by the holder after exercise of this warrant.

3. Stock Fully Paid; Reservation of Shares. All Shares that may be issued upon the exercise of the rights represented by this warrant will, upon issuance pursuant to the terms and conditions herein, be fully paid and nonassessable, and free from all preemptive rights and taxes, liens and charges with respect to the issue thereof. During the period within which the rights represented by this warrant may be exercised, the Company will at all times have authorized, and reserved for the purpose of the issue upon exercise of the purchase rights evidenced by this warrant, a sufficient number of shares of Common Stock to provide for the exercise of the rights represented by this warrant. If at any time during the term of this warrant the number of authorized but unissued shares of Common Stock shall not be sufficient to permit exercise of this warrant, the Company will take such corporate action as may, in the opinion of its counsel, be necessary to increase its authorized but unissued shares of Common Stock to such number of shares as shall be sufficient for such purposes.

4. Adjustment of Warrant Price and Number of Shares. The number of shares of Common Stock purchasable upon the exercise of this warrant and the Warrant Price shall be subject to adjustment from time to time upon the occurrence of certain events, as follows:

(a) Reclassification or Merger. In case of any reclassification or change of securities of the class issuable upon exercise of this warrant (other than a change in par value, or from par value to no par value, or from no par value to par value, or as a result of a subdivision or combination), or in case of any merger of the Company with or into another corporation (other than a merger with another corporation in which the Company is the acquiring and the surviving corporation and which does not result in any reclassification or change of outstanding securities issuable upon exercise of this warrant), or in case of any sale of all or substantially all of the assets of the Company, the Company, or such successor or purchasing corporation, as the case may be, shall duly execute and deliver to the holder of this warrant a new warrant (in form and substance reasonably satisfactory to the holder of this warrant), so that the holder of this warrant shall have the right to receive upon exercise of this warrant, at a total purchase price equal to that payable upon the exercise of the unexercised portion of this warrant, and in lieu of the shares of Common Stock theretofore issuable upon exercise of this warrant, the kind and amount of shares of stock, other securities, money and property receivable upon such reclassification, change, merger or sale by a holder of the number of shares of Common Stock then purchasable under this warrant. Any new warrant shall provide for adjustments that shall be as nearly equivalent as may be practicable to the adjustments provided for in this Section 4. The provisions of this Section 4(a) shall similarly apply to successive reclassifications, changes, mergers and sales.

(b) Subdivision or Combination of Shares. If the Company at any time while this warrant remains outstanding and unexpired shall subdivide or combine its outstanding shares of Common Stock, the Warrant Price shall be proportionately decreased and the number of Shares issuable hereunder shall be proportionately increased in the case of a subdivision and the Warrant

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Price shall be proportionately increased and the number of Shares issuable hereunder shall be proportionately decreased in the case of a combination.

(c) Stock Dividends and Other Distributions. If the Company at any time while this warrant is outstanding and unexpired shall (i) pay a dividend with respect to Common Stock payable in Common Stock, then the Warrant Price shall be adjusted, from and after the date of determination of stockholders entitled to receive such dividend or distribution, to that price determined by multiplying the Warrant Price in effect immediately prior to such date of determination by a fraction (A) the numerator of which shall be the total number of shares of Common Stock outstanding immediately prior to such dividend or distribution, and (B) the denominator of which shall be the total number of shares of Common Stock outstanding immediately after such dividend or distribution; or (ii) make any other distribution with respect to Common Stock (except any distribution specifically provided for in Sections 4(a) and 4(b)), then, in each such case, provision shall be made by the Company such that the holder of this warrant shall receive upon exercise of this warrant a proportionate share of any such dividend or distribution as though it were the holder of the Common Stock as of the record date fixed for the determination of the stockholders of the Company entitled to receive such dividend or distribution.

(d) Adjustment of Number of Shares. Upon each adjustment in the Warrant Price, the number of shares of Common Stock purchasable hereunder shall be adjusted, rounded up to the nearest whole share, to the product obtained by multiplying the number of Shares purchasable immediately prior to such adjustment in the Warrant Price by a fraction, the numerator of which shall be the Warrant Price immediately prior to such adjustment and the denominator of which shall be the Warrant Price immediately thereafter.

5. Notice of Adjustments. Whenever the Warrant Price or the number of Shares purchasable hereunder shall be adjusted pursuant to Section 4 hereof, the Company shall make a certificate signed by its chief financial officer setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such adjustment was calculated, and the Warrant Price and the number of Shares purchasable hereunder after giving effect to such adjustment, and shall cause copies of such certificate to be mailed to the holder of this warrant.

6. Fractional Shares. No fractional shares of Common Stock will be issued in connection with any exercise hereunder, but in lieu of such fractional shares the Company shall make a cash payment therefor based on the product resulting from multiplying the then fair market value of the Common Stock on the date of exercise as determined in good faith by the Company’s Board of Directors by such fraction.

7. Compliance with Act; Disposition of Warrant or Shares of Common Stock.

(a) Compliance with Act. The holder of this warrant, by acceptance hereof, agrees that this warrant, and the shares of Common Stock to be issued upon exercise hereof are being acquired for investment and that such holder will not offer, sell or otherwise dispose of this warrant, or any shares of Common Stock except under circumstances which will not result in a violation of the Securities Act of 1933, as amended (the “Securities Act”) or any applicable state securities laws. Upon exercise of this warrant, unless the Shares being acquired are registered under

3

the Securities Act and any applicable state securities laws or an exemption from such registration is available, the holder hereof shall confirm in writing that the shares of Common Stock so purchased are being acquired for investment and not with a view toward distribution or resale in violation of the Securities Act and shall confirm such other matters related thereto as may be reasonably requested by the Company. This warrant and all shares of Common Stock issued upon exercise of this warrant (unless registered under the Securities Act and any applicable state securities laws) shall be stamped or imprinted with a legend in substantially the following form:

THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. THE SECURITIES REPRESENTED HEREBY MAY NOT BE TRANSFERRED UNLESS (I) SUCH SECURITIES HAVE BEEN REGISTERED FOR SALE PURSUANT TO THE SECURITIES ACT, (II) SUCH SECURITIES MAY BE SOLD PURSUANT TO RULE 144(K) OR (III) THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO IT THAT SUCH TRANSFER MAY LAWFULLY BE MADE WITHOUT REGISTRATION UNDER THE SECURITIES ACT OR QUALIFICATION UNDER APPLICABLE STATE SECURITIES LAWS.

Said legend shall be removed by the Company, upon the request of a holder, at such time as the restrictions on the transfer of the applicable security shall have terminated. In addition, in connection with the issuance of this warrant, the holder specifically represents to the Company by acceptance of this warrant as follows:

(1) The holder is aware of the Company’s business affairs and financial condition, and has acquired information about the Company sufficient to reach an informed and knowledgeable decision to acquire this warrant. The holder is acquiring this warrant for its own account for investment purposes only and not with a view to, or for the resale in connection with, any “distribution” thereof in violation of the Securities Act.

(2) The holder understands that this warrant has not been registered under the Securities Act in reliance upon a specific exemption therefrom, which exemption depends upon, among other things, the bona fide nature of the holder’s investment intent as expressed herein.

(3) The holder further understands that this warrant must be held indefinitely unless subsequently registered under the Securities Act and qualified under any applicable state securities laws, or unless exemptions from registration and qualification are otherwise available. The holder is aware of the provisions of Rule 144, promulgated under the Securities Act.

(4) The holder is an “accredited investor” as such term is defined in Rule 501 of Regulation D promulgated under the Securities Act.

(b) Disposition of Warrant or Shares. This warrant and any shares of Common Stock acquired pursuant to the exercise or conversion of this warrant may be transferred only pursuant to a registration statement filed under the Securities Act or an exemption from such

4

registration. Subject to such restrictions, the Company shall transfer this warrant from time to time upon the books to be maintained by the Company for that purpose, upon surrender thereof for transfer properly endorsed or accompanied by appropriate instructions for transfer and such other documents as may be reasonably required by the Company, including, if required by the Company, an opinion of counsel to the effect that such transfer is exempt from the registration requirements of the Securities Act to establish that such transfer is being made in accordance with the terms hereof, and a new warrant shall be issued to the transferee and the surrendered warrant shall be cancelled by the Company. Each certificate representing this warrant or the shares of Common Stock thus transferred (except a transfer pursuant to Rule 144 or 144A) shall bear a legend as to the applicable restrictions on transferability in order to ensure compliance with such laws, unless such legend is not required in order to ensure compliance with such laws. The Company may issue stop transfer instructions to its transfer agent in connection with such restrictions.

(c) Applicability of Restrictions. Neither any restrictions of any legend described in this warrant nor the requirements of Section 7(b) above shall apply to any transfer of, or grant of a security interest in, this warrant (or the Common Stock obtainable upon exercise hereof) or any part hereof (i) to a partner of the holder if the holder is a partnership or to a member of the holder if the holder is a limited liability company, (ii) to a partnership of which the holder is a partner or to a limited liability company of which the holder is a member, or (iii) to any affiliate of the holder if the holder is a corporation; provided, however, in any such transfer, if applicable, the transferee shall on the Company’s request agree in writing to be bound by the terms of this warrant as if an original holder hereof.

8. Rights as Stockholders; Information. No holder of this warrant, as such, shall be entitled to vote or receive dividends or be deemed the holder of Common Stock issuable upon the exercise hereof for any purpose, nor shall anything contained herein be construed to confer upon the holder of this warrant, as such, any of the rights of a stockholder of the Company or any right to vote for the election of directors or upon any matter submitted to stockholders at any meeting thereof, or to receive notice of meetings, or to receive dividends or subscription rights or otherwise until this warrant shall have been exercised and the Shares purchasable upon the exercise hereof shall have become deliverable, as provided herein.

9. Right to Convert Warrant into Stock; Net Issuance.

(a) Right to Convert. In addition to and without limiting the rights of the holder under the terms of this warrant, the holder shall have the right to convert this warrant or any portion thereof (the “Conversion Right”) into shares of Common Stock as provided in this Section 9 at any time or from time to time during the term of this warrant. Upon exercise of the Conversion Right with respect to a particular number of shares subject to this warrant (the “Converted Warrant Shares”), the Company shall deliver to the holder (without payment by the holder of any exercise price or any cash or other consideration) that number of shares of fully paid and nonassessable Common Stock as is determined according to the following formula:

X = B - A

Y

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Where: X =	the number of shares of Common Stock that shall be issued to holder
Y =	the fair market value of one share of Common Stock
A =	the aggregate Warrant Price of the specified number of Converted Warrant Shares immediately prior to the exercise of the Conversion Right (i.e., the number of Converted Warrant Shares multiplied by the Warrant Price)
B =	the aggregate fair market value of the specified number of Converted Warrant Shares (i.e., the number of Converted Warrant Shares multiplied by the fair market value of one Converted Warrant Share)

No fractional shares shall be issuable upon exercise of the Conversion Right, and, if the number of shares to be issued determined in accordance with the foregoing formula is other than a whole number, the Company shall pay to the holder an amount in cash equal to the fair market value of the resulting fractional share on the Conversion Date (as hereinafter defined).

(b) Method of Exercise. The Conversion Right may be exercised by the holder by the surrender of this warrant at the principal office of the Company together with a written statement (which may be in the form of Exhibit A-1) specifying that the holder thereby intends to exercise the Conversion Right and indicating the number of shares subject to this warrant which are being surrendered (referred to in Section 9(a) hereof as the Converted Warrant Shares) in exercise of the Conversion Right. Such conversion shall be effective upon receipt by the Company of this warrant together with the aforesaid written statement, or on such later date as is specified therein (the “Conversion Date”). Certificates for the shares issuable upon exercise of the Conversion Right and, if applicable, a new warrant evidencing the balance of the shares remaining subject to this warrant, shall be issued as of the Conversion Date and shall be delivered to the holder within thirty (30) days following the Conversion Date.

(c) Determination of Fair Market Value. For purposes of this Section 9, “fair market value” of a share of Common Stock as of a particular date (the “Determination Date”) shall mean: (i) if traded on a securities exchange, the fair market value of the Common Stock shall be deemed to be the average of the closing prices of the Common Stock on such exchange over the five trading days immediately prior to the Determination Date as reported by Bloomberg Financial Markets (or a comparable reporting service of national reputation selected by the Company and reasonably acceptable to the holder if Bloomberg Financial Markets is not then reporting sales prices of such security) (collectively, “Bloomberg”); (ii) if traded on the Nasdaq Stock Market or other over-the-counter system, the fair market value of the Common Stock shall be deemed to be the average of the closing bid prices of the Common Stock over the five trading days immediately prior to the Determination Date as reported by Bloomberg; and (iii) if there is no public market for the Common Stock, then fair market value shall be determined by the Board of Directors of the Company in good faith.

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10. Representations and Warranties. The Company represents and warrants to the holder of this warrant as follows:

(a) This warrant has been duly authorized and executed by the Company and is a valid and binding obligation of the Company enforceable in accordance with its terms, subject to laws of general application relating to bankruptcy, insolvency and the relief of debtors and the rules of law or principles at equity governing specific performance, injunctive relief and other equitable remedies.

(b) The Shares have been duly authorized and reserved for issuance by the Company and, when issued in accordance with the terms hereof, will be validly issued, fully paid and nonassessable and free from preemptive rights.

(c) The execution and delivery of this warrant are not, and the issuance of the Shares upon exercise of this warrant in accordance with the terms hereof will not be, inconsistent with the Company’s certificate of incorporation or bylaws, do not and will not contravene any law, governmental rule or regulation, judgment or order applicable to the Company, and do not and will not conflict with or contravene any provision of, or constitute a default under, any indenture, mortgage, contract or other instrument of which the Company is a party or by which it is bound or require the consent or approval of, the giving of notice to, the registration or filing with or the taking of any action in respect of or by, any federal, state or local government authority or agency or other person, except for the filing of notices pursuant to federal and state securities laws, which filings will be effected by the time required thereby.

11. Modification and Waiver. This warrant and any provision hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of the same is sought.

12. Notices. Any notice, request, communication or other document required or permitted to be given or delivered to the holder hereof or the Company shall be delivered, or shall be sent by certified or registered mail, postage prepaid, to each such holder at its address as shown on the books of the Company or to the Company at the address indicated therefor on the signature page of this warrant.

13. Binding Effect on Successors. This warrant shall be binding upon any corporation succeeding the Company by merger, consolidation or acquisition of all or substantially all of the Company’s assets, and all of the obligations of the Company relating to the Common Stock issuable upon the exercise or conversion of this warrant shall survive the exercise, conversion and termination of this warrant and all of the covenants and agreements of the Company shall inure to the benefit of the successors and assigns of the holder hereof.

14. Lost Warrants or Stock Certificates. The Company covenants to the holder hereof that, upon receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this warrant or any stock certificate and, in the case of any such loss, theft or destruction, upon receipt of an indemnity reasonably satisfactory to the Company, or in the case of any such mutilation upon surrender and cancellation of such warrant or stock certificate, the Company will make and deliver a new warrant or stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or mutilated warrant or stock certificate.

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15. Descriptive Headings. The descriptive headings of the various sections of this warrant are inserted for convenience only and do not constitute a part of this warrant. The language in this warrant shall be construed as to its fair meaning without regard to which party drafted this warrant.

16. Governing Law. This warrant shall be construed and enforced in accordance with, and the rights of the parties shall be governed by, the laws of the State of California.

17. Remedies. In case any one or more of the covenants and agreements contained in this warrant shall have been breached, the holder hereof (in the case of a breach by the Company), or the Company (in the case of a breach by a holder), may proceed to protect and enforce their or its rights either by suit in equity and/or by action at law, including, but not limited to, an action for damages as a result of any such breach and/or an action for specific performance of any such covenant or agreement contained in this warrant.

18. No Impairment of Rights. The Company will not, by amendment of its certificate of incorporation or through any other means, avoid or seek to avoid the observance or performance of any of the terms of this warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the holder of this warrant against impairment.

19. Severability. The invalidity or unenforceability of any provision of this warrant in any jurisdiction shall not affect the validity or enforceability of such provision in any other jurisdiction, or affect any other provision of this warrant, which shall remain in full force and effect.

20. Recovery of Litigation Costs. If any legal action or other proceeding is brought for the enforcement of this warrant, or because of an alleged dispute, breach, default, or misrepresentation in connection with any of the provisions of this warrant, the successful or prevailing party or parties shall be entitled to recover reasonable attorneys’ fees and other costs incurred in that action or proceeding, in addition to any other relief to which it or they may be entitled.

21. Entire Agreement; Modification. This warrant constitutes the entire agreement between the parties pertaining to the subject matter contained in it and supersedes all prior and contemporaneous agreements, representations, and undertakings of the parties, whether oral or written, with respect to such subject matter.

(Signature page follows)

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The Company has caused this Warrant to Purchase Shares of Common Stock of Sunesis Pharmaceuticals, Inc. to be duly executed and delivered as of the Date of Grant specified above.

SUNESIS PHARMACEUTICALS, INC.
By:	/s/ Daryl B. Winter, Ph.D.
Name:	Daryl B. Winter
Title:	Sr. Vice President and General Counsel
Address:	341 Oyster Point Boulevard South San Francisco, CA 94080

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EXHIBIT A-1

NOTICE OF EXERCISE

To: SUNESIS PHARMACEUTICALS, INC. (the “Company”)

1. The undersigned hereby:

¨ elects to purchase              shares of common stock of the Company pursuant to the terms of the attached warrant, and tenders herewith payment of the purchase price of such shares in full, or

¨ elects to exercise its net issuance rights pursuant to Section 9 of the attached warrant with respect to              shares of common stock.

2. Please issue a certificate or certificates representing              shares in the name of the undersigned or in such other name or names as are specified below:

(Name)

(Address)

3. The undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in connection with, the distribution thereof and that the undersigned has no present intention of distributing or reselling such shares, all except as in compliance with applicable securities laws.

(Signature)

(Date)

Exhibit D-2

THIS WARRANT AND THE UNDERLYING SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. THIS WARRANT AND THE UNDERLYING SECURITIES MAY NOT BE TRANSFERRED UNLESS (I) THIS WARRANT AND THE UNDERLYING SECURITIES HAVE BEEN REGISTERED FOR SALE PURSUANT TO THE SECURITIES ACT, (II) THIS WARRANT AND THE UNDERLYING SECURITIES MAY BE SOLD PURSUANT TO RULE 144(K) OR (III) THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO IT THAT SUCH TRANSFER MAY LAWFULLY BE MADE WITHOUT REGISTRATION UNDER THE SECURITIES ACT OR QUALIFICATION UNDER APPLICABLE STATE SECURITIES LAWS.

WARRANT TO PURCHASE SHARES OF COMMON STOCK

OF SUNESIS PHARMACEUTICALS, INC.

THIS CERTIFIES THAT, for value received, Warburg, Pincus Netherlands Equity Partners I, C.V. is entitled to subscribe for and purchase 12,077 fully paid and nonassessable shares (the “Shares”) of common stock, par value $0.0001 per share (the “Common Stock”), of Sunesis Pharmaceuticals, Inc., a Delaware corporation (the “Company”), at a price per share equal to $6.21 (such price and such other price as shall result, from time to time, from the adjustments specified in Section 4 hereof is herein referred to as the “Warrant Price”), upon the terms and subject to the conditions hereinafter set forth.

1. Term. The purchase right represented by this warrant is exercisable, in whole or in part, at any time and from time to time from March 17, 2006 (the “Date of Grant”) until the 7-year anniversary of the Date of Grant.

2. Method of Exercise; Payment; Issuance of New Warrant. Subject to Section 1 hereof, the purchase right represented by this warrant may be exercised by the holder hereof, in whole or in part and from time to time, at the election of the holder hereof, by (a) the surrender of this warrant (with the notice of exercise substantially in the form attached hereto as Exhibit A-1 duly completed and executed) at the principal office of the Company and by the payment to the Company, by certified or bank check, or by wire transfer to an account designated by the Company (a “Wire Transfer”) of an amount equal to the then applicable Warrant Price multiplied by the number of Shares then being purchased; or (b) exercise of the “net issuance” right provided for in Section 9 hereof. The person or persons in whose name(s) any certificate(s) representing shares of Common Stock shall be issuable upon exercise of this warrant shall be deemed to have become the holder(s) of record of, and shall be treated for all purposes as the record holder(s) of, the shares represented thereby (and such shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this warrant is exercised. In the event of any exercise of the rights represented by this warrant, certificates for the shares of stock so purchased shall be delivered to the holder hereof as soon as practicable and in any event within thirty (30) days after such exercise and, unless this warrant has been fully exercised or expired, a new warrant representing the portion of the Shares, if any, with respect to which this warrant shall not then have been exercised shall also be issued to the holder hereof as soon as practicable and in any event within such thirty-day period;

provided, however, if requested by the holder of this warrant, the Company shall use reasonable efforts to cause its transfer agent to deliver the certificate representing Shares issued upon exercise of this warrant to a broker or other person (as directed by the holder exercising this warrant) within the time period required to settle any trade made by the holder after exercise of this warrant.

3. Stock Fully Paid; Reservation of Shares. All Shares that may be issued upon the exercise of the rights represented by this warrant will, upon issuance pursuant to the terms and conditions herein, be fully paid and nonassessable, and free from all preemptive rights and taxes, liens and charges with respect to the issue thereof. During the period within which the rights represented by this warrant may be exercised, the Company will at all times have authorized, and reserved for the purpose of the issue upon exercise of the purchase rights evidenced by this warrant, a sufficient number of shares of Common Stock to provide for the exercise of the rights represented by this warrant. If at any time during the term of this warrant the number of authorized but unissued shares of Common Stock shall not be sufficient to permit exercise of this warrant, the Company will take such corporate action as may, in the opinion of its counsel, be necessary to increase its authorized but unissued shares of Common Stock to such number of shares as shall be sufficient for such purposes.

4. Adjustment of Warrant Price and Number of Shares. The number of shares of Common Stock purchasable upon the exercise of this warrant and the Warrant Price shall be subject to adjustment from time to time upon the occurrence of certain events, as follows:

(a) Reclassification or Merger. In case of any reclassification or change of securities of the class issuable upon exercise of this warrant (other than a change in par value, or from par value to no par value, or from no par value to par value, or as a result of a subdivision or combination), or in case of any merger of the Company with or into another corporation (other than a merger with another corporation in which the Company is the acquiring and the surviving corporation and which does not result in any reclassification or change of outstanding securities issuable upon exercise of this warrant), or in case of any sale of all or substantially all of the assets of the Company, the Company, or such successor or purchasing corporation, as the case may be, shall duly execute and deliver to the holder of this warrant a new warrant (in form and substance reasonably satisfactory to the holder of this warrant), so that the holder of this warrant shall have the right to receive upon exercise of this warrant, at a total purchase price equal to that payable upon the exercise of the unexercised portion of this warrant, and in lieu of the shares of Common Stock theretofore issuable upon exercise of this warrant, the kind and amount of shares of stock, other securities, money and property receivable upon such reclassification, change, merger or sale by a holder of the number of shares of Common Stock then purchasable under this warrant. Any new warrant shall provide for adjustments that shall be as nearly equivalent as may be practicable to the adjustments provided for in this Section 4. The provisions of this Section 4(a) shall similarly apply to successive reclassifications, changes, mergers and sales.

(b) Subdivision or Combination of Shares. If the Company at any time while this warrant remains outstanding and unexpired shall subdivide or combine its outstanding shares of Common Stock, the Warrant Price shall be proportionately decreased and the number of Shares issuable hereunder shall be proportionately increased in the case of a subdivision and the Warrant

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Price shall be proportionately increased and the number of Shares issuable hereunder shall be proportionately decreased in the case of a combination.

(c) Stock Dividends and Other Distributions. If the Company at any time while this warrant is outstanding and unexpired shall (i) pay a dividend with respect to Common Stock payable in Common Stock, then the Warrant Price shall be adjusted, from and after the date of determination of stockholders entitled to receive such dividend or distribution, to that price determined by multiplying the Warrant Price in effect immediately prior to such date of determination by a fraction (A) the numerator of which shall be the total number of shares of Common Stock outstanding immediately prior to such dividend or distribution, and (B) the denominator of which shall be the total number of shares of Common Stock outstanding immediately after such dividend or distribution; or (ii) make any other distribution with respect to Common Stock (except any distribution specifically provided for in Sections 4(a) and 4(b)), then, in each such case, provision shall be made by the Company such that the holder of this warrant shall receive upon exercise of this warrant a proportionate share of any such dividend or distribution as though it were the holder of the Common Stock as of the record date fixed for the determination of the stockholders of the Company entitled to receive such dividend or distribution.

(d) Adjustment of Number of Shares. Upon each adjustment in the Warrant Price, the number of shares of Common Stock purchasable hereunder shall be adjusted, rounded up to the nearest whole share, to the product obtained by multiplying the number of Shares purchasable immediately prior to such adjustment in the Warrant Price by a fraction, the numerator of which shall be the Warrant Price immediately prior to such adjustment and the denominator of which shall be the Warrant Price immediately thereafter.

5. Notice of Adjustments. Whenever the Warrant Price or the number of Shares purchasable hereunder shall be adjusted pursuant to Section 4 hereof, the Company shall make a certificate signed by its chief financial officer setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such adjustment was calculated, and the Warrant Price and the number of Shares purchasable hereunder after giving effect to such adjustment, and shall cause copies of such certificate to be mailed to the holder of this warrant.

6. Fractional Shares. No fractional shares of Common Stock will be issued in connection with any exercise hereunder, but in lieu of such fractional shares the Company shall make a cash payment therefor based on the product resulting from multiplying the then fair market value of the Common Stock on the date of exercise as determined in good faith by the Company’s Board of Directors by such fraction.

7. Compliance with Act; Disposition of Warrant or Shares of Common Stock.

(a) Compliance with Act. The holder of this warrant, by acceptance hereof, agrees that this warrant, and the shares of Common Stock to be issued upon exercise hereof are being acquired for investment and that such holder will not offer, sell or otherwise dispose of this warrant, or any shares of Common Stock except under circumstances which will not result in a violation of the Securities Act of 1933, as amended (the “Securities Act”) or any applicable state securities laws. Upon exercise of this warrant, unless the Shares being acquired are registered under

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the Securities Act and any applicable state securities laws or an exemption from such registration is available, the holder hereof shall confirm in writing that the shares of Common Stock so purchased are being acquired for investment and not with a view toward distribution or resale in violation of the Securities Act and shall confirm such other matters related thereto as may be reasonably requested by the Company. This warrant and all shares of Common Stock issued upon exercise of this warrant (unless registered under the Securities Act and any applicable state securities laws) shall be stamped or imprinted with a legend in substantially the following form:

THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. THE SECURITIES REPRESENTED HEREBY MAY NOT BE TRANSFERRED UNLESS (I) SUCH SECURITIES HAVE BEEN REGISTERED FOR SALE PURSUANT TO THE SECURITIES ACT, (II) SUCH SECURITIES MAY BE SOLD PURSUANT TO RULE 144(K) OR (III) THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO IT THAT SUCH TRANSFER MAY LAWFULLY BE MADE WITHOUT REGISTRATION UNDER THE SECURITIES ACT OR QUALIFICATION UNDER APPLICABLE STATE SECURITIES LAWS.

Said legend shall be removed by the Company, upon the request of a holder, at such time as the restrictions on the transfer of the applicable security shall have terminated. In addition, in connection with the issuance of this warrant, the holder specifically represents to the Company by acceptance of this warrant as follows:

(1) The holder is aware of the Company’s business affairs and financial condition, and has acquired information about the Company sufficient to reach an informed and knowledgeable decision to acquire this warrant. The holder is acquiring this warrant for its own account for investment purposes only and not with a view to, or for the resale in connection with, any “distribution” thereof in violation of the Securities Act.

(2) The holder understands that this warrant has not been registered under the Securities Act in reliance upon a specific exemption therefrom, which exemption depends upon, among other things, the bona fide nature of the holder’s investment intent as expressed herein.

(3) The holder further understands that this warrant must be held indefinitely unless subsequently registered under the Securities Act and qualified under any applicable state securities laws, or unless exemptions from registration and qualification are otherwise available. The holder is aware of the provisions of Rule 144, promulgated under the Securities Act.

(4) The holder is an “accredited investor” as such term is defined in Rule 501 of Regulation D promulgated under the Securities Act.

(b) Disposition of Warrant or Shares. This warrant and any shares of Common Stock acquired pursuant to the exercise or conversion of this warrant may be transferred only pursuant to a registration statement filed under the Securities Act or an exemption from such

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registration. Subject to such restrictions, the Company shall transfer this warrant from time to time upon the books to be maintained by the Company for that purpose, upon surrender thereof for transfer properly endorsed or accompanied by appropriate instructions for transfer and such other documents as may be reasonably required by the Company, including, if required by the Company, an opinion of counsel to the effect that such transfer is exempt from the registration requirements of the Securities Act to establish that such transfer is being made in accordance with the terms hereof, and a new warrant shall be issued to the transferee and the surrendered warrant shall be cancelled by the Company. Each certificate representing this warrant or the shares of Common Stock thus transferred (except a transfer pursuant to Rule 144 or 144A) shall bear a legend as to the applicable restrictions on transferability in order to ensure compliance with such laws, unless such legend is not required in order to ensure compliance with such laws. The Company may issue stop transfer instructions to its transfer agent in connection with such restrictions.

(c) Applicability of Restrictions. Neither any restrictions of any legend described in this warrant nor the requirements of Section 7(b) above shall apply to any transfer of, or grant of a security interest in, this warrant (or the Common Stock obtainable upon exercise hereof) or any part hereof (i) to a partner of the holder if the holder is a partnership or to a member of the holder if the holder is a limited liability company, (ii) to a partnership of which the holder is a partner or to a limited liability company of which the holder is a member, or (iii) to any affiliate of the holder if the holder is a corporation; provided, however, in any such transfer, if applicable, the transferee shall on the Company’s request agree in writing to be bound by the terms of this warrant as if an original holder hereof.

8. Rights as Stockholders; Information. No holder of this warrant, as such, shall be entitled to vote or receive dividends or be deemed the holder of Common Stock issuable upon the exercise hereof for any purpose, nor shall anything contained herein be construed to confer upon the holder of this warrant, as such, any of the rights of a stockholder of the Company or any right to vote for the election of directors or upon any matter submitted to stockholders at any meeting thereof, or to receive notice of meetings, or to receive dividends or subscription rights or otherwise until this warrant shall have been exercised and the Shares purchasable upon the exercise hereof shall have become deliverable, as provided herein.

9. Right to Convert Warrant into Stock; Net Issuance.

(a) Right to Convert. In addition to and without limiting the rights of the holder under the terms of this warrant, the holder shall have the right to convert this warrant or any portion thereof (the “Conversion Right”) into shares of Common Stock as provided in this Section 9 at any time or from time to time during the term of this warrant. Upon exercise of the Conversion Right with respect to a particular number of shares subject to this warrant (the “Converted Warrant Shares”), the Company shall deliver to the holder (without payment by the holder of any exercise price or any cash or other consideration) that number of shares of fully paid and nonassessable Common Stock as is determined according to the following formula:

X = B - A

          Y

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Where: X=	the number of shares of Common Stock that shall be issued to holder
Y =	the fair market value of one share of Common Stock
A =	the aggregate Warrant Price of the specified number of Converted Warrant Shares immediately prior to the exercise of the Conversion Right (i.e., the number of Converted Warrant Shares multiplied by the Warrant Price)
B =	the aggregate fair market value of the specified number of Converted Warrant Shares (i.e., the number of Converted Warrant Shares multiplied by the fair market value of one Converted Warrant Share)

No fractional shares shall be issuable upon exercise of the Conversion Right, and, if the number of shares to be issued determined in accordance with the foregoing formula is other than a whole number, the Company shall pay to the holder an amount in cash equal to the fair market value of the resulting fractional share on the Conversion Date (as hereinafter defined).

(b) Method of Exercise. The Conversion Right may be exercised by the holder by the surrender of this warrant at the principal office of the Company together with a written statement (which may be in the form of Exhibit A-1) specifying that the holder thereby intends to exercise the Conversion Right and indicating the number of shares subject to this warrant which are being surrendered (referred to in Section 9(a) hereof as the Converted Warrant Shares) in exercise of the Conversion Right. Such conversion shall be effective upon receipt by the Company of this warrant together with the aforesaid written statement, or on such later date as is specified therein (the “Conversion Date”). Certificates for the shares issuable upon exercise of the Conversion Right and, if applicable, a new warrant evidencing the balance of the shares remaining subject to this warrant, shall be issued as of the Conversion Date and shall be delivered to the holder within thirty (30) days following the Conversion Date.

(c) Determination of Fair Market Value. For purposes of this Section 9, “fair market value” of a share of Common Stock as of a particular date (the “Determination Date”) shall mean: (i) if traded on a securities exchange, the fair market value of the Common Stock shall be deemed to be the average of the closing prices of the Common Stock on such exchange over the five trading days immediately prior to the Determination Date as reported by Bloomberg Financial Markets (or a comparable reporting service of national reputation selected by the Company and reasonably acceptable to the holder if Bloomberg Financial Markets is not then reporting sales prices of such security) (collectively, “Bloomberg”); (ii) if traded on the Nasdaq Stock Market or other over-the-counter system, the fair market value of the Common Stock shall be deemed to be the average of the closing bid prices of the Common Stock over the five trading days immediately prior to the Determination Date as reported by Bloomberg; and (iii) if there is no public market for the Common Stock, then fair market value shall be determined by the Board of Directors of the Company in good faith.

10. Representations and Warranties. The Company represents and warrants to the holder of this warrant as follows:

(a) This warrant has been duly authorized and executed by the Company and is a valid and binding obligation of the Company enforceable in accordance with its terms, subject to laws of general application relating to bankruptcy, insolvency and the relief of debtors and the rules of law or principles at equity governing specific performance, injunctive relief and other equitable remedies.

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(b) The Shares have been duly authorized and reserved for issuance by the Company and, when issued in accordance with the terms hereof, will be validly issued, fully paid and nonassessable and free from preemptive rights.

(c) The execution and delivery of this warrant are not, and the issuance of the Shares upon exercise of this warrant in accordance with the terms hereof will not be, inconsistent with the Company’s certificate of incorporation or bylaws, do not and will not contravene any law, governmental rule or regulation, judgment or order applicable to the Company, and do not and will not conflict with or contravene any provision of, or constitute a default under, any indenture, mortgage, contract or other instrument of which the Company is a party or by which it is bound or require the consent or approval of, the giving of notice to, the registration or filing with or the taking of any action in respect of or by, any federal, state or local government authority or agency or other person, except for the filing of notices pursuant to federal and state securities laws, which filings will be effected by the time required thereby.

11. Modification and Waiver. This warrant and any provision hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of the same is sought.

12. Notices. Any notice, request, communication or other document required or permitted to be given or delivered to the holder hereof or the Company shall be delivered, or shall be sent by certified or registered mail, postage prepaid, to each such holder at its address as shown on the books of the Company or to the Company at the address indicated therefor on the signature page of this warrant.

13. Binding Effect on Successors. This warrant shall be binding upon any corporation succeeding the Company by merger, consolidation or acquisition of all or substantially all of the Company’s assets, and all of the obligations of the Company relating to the Common Stock issuable upon the exercise or conversion of this warrant shall survive the exercise, conversion and termination of this warrant and all of the covenants and agreements of the Company shall inure to the benefit of the successors and assigns of the holder hereof.

14. Lost Warrants or Stock Certificates. The Company covenants to the holder hereof that, upon receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this warrant or any stock certificate and, in the case of any such loss, theft or destruction, upon receipt of an indemnity reasonably satisfactory to the Company, or in the case of any such mutilation upon surrender and cancellation of such warrant or stock certificate, the Company will make and deliver a new warrant or stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or mutilated warrant or stock certificate.

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15. Descriptive Headings. The descriptive headings of the various sections of this warrant are inserted for convenience only and do not constitute a part of this warrant. The language in this warrant shall be construed as to its fair meaning without regard to which party drafted this warrant.

16. Governing Law. This warrant shall be construed and enforced in accordance with, and the rights of the parties shall be governed by, the laws of the State of California.

17. Remedies. In case any one or more of the covenants and agreements contained in this warrant shall have been breached, the holder hereof (in the case of a breach by the Company), or the Company (in the case of a breach by a holder), may proceed to protect and enforce their or its rights either by suit in equity and/or by action at law, including, but not limited to, an action for damages as a result of any such breach and/or an action for specific performance of any such covenant or agreement contained in this warrant.

18. No Impairment of Rights. The Company will not, by amendment of its certificate of incorporation or through any other means, avoid or seek to avoid the observance or performance of any of the terms of this warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the holder of this warrant against impairment.

19. Severability. The invalidity or unenforceability of any provision of this warrant in any jurisdiction shall not affect the validity or enforceability of such provision in any other jurisdiction, or affect any other provision of this warrant, which shall remain in full force and effect.

20. Recovery of Litigation Costs. If any legal action or other proceeding is brought for the enforcement of this warrant, or because of an alleged dispute, breach, default, or misrepresentation in connection with any of the provisions of this warrant, the successful or prevailing party or parties shall be entitled to recover reasonable attorneys’ fees and other costs incurred in that action or proceeding, in addition to any other relief to which it or they may be entitled.

21. Entire Agreement; Modification. This warrant constitutes the entire agreement between the parties pertaining to the subject matter contained in it and supersedes all prior and contemporaneous agreements, representations, and undertakings of the parties, whether oral or written, with respect to such subject matter.

(Signature page follows)

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The Company has caused this Warrant to Purchase Shares of Common Stock of Sunesis Pharmaceuticals, Inc. to be duly executed and delivered as of the Date of Grant specified above.

SUNESIS PHARMACEUTICALS, INC.
By:	/s/ Daryl B. Winter, Ph.D.
Name:	Daryl B. Winter
Title:	Senior Vice President and General Counsel
Address:	341 Oyster Point Boulevard South San Francisco, CA 94080

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EXHIBIT A-1

NOTICE OF EXERCISE

To: SUNESIS PHARMACEUTICALS, INC. (the “Company”)

1. The undersigned hereby:

¨ elects to purchase              shares of common stock of the Company pursuant to the terms of the attached warrant, and tenders herewith payment of the purchase price of such shares in full, or

¨ elects to exercise its net issuance rights pursuant to Section 9 of the attached warrant with respect to              shares of common stock.

2. Please issue a certificate or certificates representing              shares in the name of the undersigned or in such other name or names as are specified below:

(Name)

(Address)

3. The undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in connection with, the distribution thereof and that the undersigned has no present intention of distributing or reselling such shares, all except as in compliance with applicable securities laws.

(Signature)

(Date)

Exhibit D-3

THIS WARRANT AND THE UNDERLYING SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. THIS WARRANT AND THE UNDERLYING SECURITIES MAY NOT BE TRANSFERRED UNLESS (I) THIS WARRANT AND THE UNDERLYING SECURITIES HAVE BEEN REGISTERED FOR SALE PURSUANT TO THE SECURITIES ACT, (II) THIS WARRANT AND THE UNDERLYING SECURITIES MAY BE SOLD PURSUANT TO RULE 144(K) OR (III) THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO IT THAT SUCH TRANSFER MAY LAWFULLY BE MADE WITHOUT REGISTRATION UNDER THE SECURITIES ACT OR QUALIFICATION UNDER APPLICABLE STATE SECURITIES LAWS.

WARRANT TO PURCHASE SHARES OF COMMON STOCK

OF SUNESIS PHARMACEUTICALS, INC.

THIS CERTIFIES THAT, for value received, Warburg, Pincus Netherlands Equity Partners III, C.V. is entitled to subscribe for and purchase 1,208 fully paid and nonassessable shares (the “Shares”) of common stock, par value $0.0001 per share (the “Common Stock”), of Sunesis Pharmaceuticals, Inc., a Delaware corporation (the “Company”), at a price per share equal to $6.21 (such price and such other price as shall result, from time to time, from the adjustments specified in Section 4 hereof is herein referred to as the “Warrant Price”), upon the terms and subject to the conditions hereinafter set forth.

1. Term. The purchase right represented by this warrant is exercisable, in whole or in part, at any time and from time to time from March 17, 2006 (the “Date of Grant”) until the 7-year anniversary of the Date of Grant.

2. Method of Exercise; Payment; Issuance of New Warrant. Subject to Section 1 hereof, the purchase right represented by this warrant may be exercised by the holder hereof, in whole or in part and from time to time, at the election of the holder hereof, by (a) the surrender of this warrant (with the notice of exercise substantially in the form attached hereto as Exhibit A-1 duly completed and executed) at the principal office of the Company and by the payment to the Company, by certified or bank check, or by wire transfer to an account designated by the Company (a “Wire Transfer”) of an amount equal to the then applicable Warrant Price multiplied by the number of Shares then being purchased; or (b) exercise of the “net issuance” right provided for in Section 9 hereof. The person or persons in whose name(s) any certificate(s) representing shares of Common Stock shall be issuable upon exercise of this warrant shall be deemed to have become the holder(s) of record of, and shall be treated for all purposes as the record holder(s) of, the shares represented thereby (and such shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this warrant is exercised. In the event of any exercise of the rights represented by this warrant, certificates for the shares of stock so purchased shall be delivered to the holder hereof as soon as practicable and in any event within thirty (30) days after such exercise and, unless this warrant has been fully exercised or expired, a new warrant representing the portion of the Shares, if any, with respect to which this warrant shall not then have been exercised shall also be issued to the holder hereof as soon as practicable and in any event within such thirty-day period;

provided, however, if requested by the holder of this warrant, the Company shall use reasonable efforts to cause its transfer agent to deliver the certificate representing Shares issued upon exercise of this warrant to a broker or other person (as directed by the holder exercising this warrant) within the time period required to settle any trade made by the holder after exercise of this warrant.

3. Stock Fully Paid; Reservation of Shares. All Shares that may be issued upon the exercise of the rights represented by this warrant will, upon issuance pursuant to the terms and conditions herein, be fully paid and nonassessable, and free from all preemptive rights and taxes, liens and charges with respect to the issue thereof. During the period within which the rights represented by this warrant may be exercised, the Company will at all times have authorized, and reserved for the purpose of the issue upon exercise of the purchase rights evidenced by this warrant, a sufficient number of shares of Common Stock to provide for the exercise of the rights represented by this warrant. If at any time during the term of this warrant the number of authorized but unissued shares of Common Stock shall not be sufficient to permit exercise of this warrant, the Company will take such corporate action as may, in the opinion of its counsel, be necessary to increase its authorized but unissued shares of Common Stock to such number of shares as shall be sufficient for such purposes.

4. Adjustment of Warrant Price and Number of Shares. The number of shares of Common Stock purchasable upon the exercise of this warrant and the Warrant Price shall be subject to adjustment from time to time upon the occurrence of certain events, as follows:

(a) Reclassification or Merger. In case of any reclassification or change of securities of the class issuable upon exercise of this warrant (other than a change in par value, or from par value to no par value, or from no par value to par value, or as a result of a subdivision or combination), or in case of any merger of the Company with or into another corporation (other than a merger with another corporation in which the Company is the acquiring and the surviving corporation and which does not result in any reclassification or change of outstanding securities issuable upon exercise of this warrant), or in case of any sale of all or substantially all of the assets of the Company, the Company, or such successor or purchasing corporation, as the case may be, shall duly execute and deliver to the holder of this warrant a new warrant (in form and substance reasonably satisfactory to the holder of this warrant), so that the holder of this warrant shall have the right to receive upon exercise of this warrant, at a total purchase price equal to that payable upon the exercise of the unexercised portion of this warrant, and in lieu of the shares of Common Stock theretofore issuable upon exercise of this warrant, the kind and amount of shares of stock, other securities, money and property receivable upon such reclassification, change, merger or sale by a holder of the number of shares of Common Stock then purchasable under this warrant. Any new warrant shall provide for adjustments that shall be as nearly equivalent as may be practicable to the adjustments provided for in this Section 4. The provisions of this Section 4(a) shall similarly apply to successive reclassifications, changes, mergers and sales.

(b) Subdivision or Combination of Shares. If the Company at any time while this warrant remains outstanding and unexpired shall subdivide or combine its outstanding shares of Common Stock, the Warrant Price shall be proportionately decreased and the number of Shares issuable hereunder shall be proportionately increased in the case of a subdivision and the Warrant

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Price shall be proportionately increased and the number of Shares issuable hereunder shall be proportionately decreased in the case of a combination.

(c) Stock Dividends and Other Distributions. If the Company at any time while this warrant is outstanding and unexpired shall (i) pay a dividend with respect to Common Stock payable in Common Stock, then the Warrant Price shall be adjusted, from and after the date of determination of stockholders entitled to receive such dividend or distribution, to that price determined by multiplying the Warrant Price in effect immediately prior to such date of determination by a fraction (A) the numerator of which shall be the total number of shares of Common Stock outstanding immediately prior to such dividend or distribution, and (B) the denominator of which shall be the total number of shares of Common Stock outstanding immediately after such dividend or distribution; or (ii) make any other distribution with respect to Common Stock (except any distribution specifically provided for in Sections 4(a) and 4(b)), then, in each such case, provision shall be made by the Company such that the holder of this warrant shall receive upon exercise of this warrant a proportionate share of any such dividend or distribution as though it were the holder of the Common Stock as of the record date fixed for the determination of the stockholders of the Company entitled to receive such dividend or distribution.

(d) Adjustment of Number of Shares. Upon each adjustment in the Warrant Price, the number of shares of Common Stock purchasable hereunder shall be adjusted, rounded up to the nearest whole share, to the product obtained by multiplying the number of Shares purchasable immediately prior to such adjustment in the Warrant Price by a fraction, the numerator of which shall be the Warrant Price immediately prior to such adjustment and the denominator of which shall be the Warrant Price immediately thereafter.

5. Notice of Adjustments. Whenever the Warrant Price or the number of Shares purchasable hereunder shall be adjusted pursuant to Section 4 hereof, the Company shall make a certificate signed by its chief financial officer setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such adjustment was calculated, and the Warrant Price and the number of Shares purchasable hereunder after giving effect to such adjustment, and shall cause copies of such certificate to be mailed to the holder of this warrant.

6. Fractional Shares. No fractional shares of Common Stock will be issued in connection with any exercise hereunder, but in lieu of such fractional shares the Company shall make a cash payment therefor based on the product resulting from multiplying the then fair market value of the Common Stock on the date of exercise as determined in good faith by the Company’s Board of Directors by such fraction.

7. Compliance with Act; Disposition of Warrant or Shares of Common Stock.

(a) Compliance with Act. The holder of this warrant, by acceptance hereof, agrees that this warrant, and the shares of Common Stock to be issued upon exercise hereof are being acquired for investment and that such holder will not offer, sell or otherwise dispose of this warrant, or any shares of Common Stock except under circumstances which will not result in a violation of the Securities Act of 1933, as amended (the “Securities Act”) or any applicable state securities laws. Upon exercise of this warrant, unless the Shares being acquired are registered under

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the Securities Act and any applicable state securities laws or an exemption from such registration is available, the holder hereof shall confirm in writing that the shares of Common Stock so purchased are being acquired for investment and not with a view toward distribution or resale in violation of the Securities Act and shall confirm such other matters related thereto as may be reasonably requested by the Company. This warrant and all shares of Common Stock issued upon exercise of this warrant (unless registered under the Securities Act and any applicable state securities laws) shall be stamped or imprinted with a legend in substantially the following form:

THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS. THE SECURITIES REPRESENTED HEREBY MAY NOT BE TRANSFERRED UNLESS (I) SUCH SECURITIES HAVE BEEN REGISTERED FOR SALE PURSUANT TO THE SECURITIES ACT, (II) SUCH SECURITIES MAY BE SOLD PURSUANT TO RULE 144(K) OR (III) THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO IT THAT SUCH TRANSFER MAY LAWFULLY BE MADE WITHOUT REGISTRATION UNDER THE SECURITIES ACT OR QUALIFICATION UNDER APPLICABLE STATE SECURITIES LAWS.

Said legend shall be removed by the Company, upon the request of a holder, at such time as the restrictions on the transfer of the applicable security shall have terminated. In addition, in connection with the issuance of this warrant, the holder specifically represents to the Company by acceptance of this warrant as follows:

(1) The holder is aware of the Company’s business affairs and financial condition, and has acquired information about the Company sufficient to reach an informed and knowledgeable decision to acquire this warrant. The holder is acquiring this warrant for its own account for investment purposes only and not with a view to, or for the resale in connection with, any “distribution” thereof in violation of the Securities Act.

(2) The holder understands that this warrant has not been registered under the Securities Act in reliance upon a specific exemption therefrom, which exemption depends upon, among other things, the bona fide nature of the holder’s investment intent as expressed herein.

(3) The holder further understands that this warrant must be held indefinitely unless subsequently registered under the Securities Act and qualified under any applicable state securities laws, or unless exemptions from registration and qualification are otherwise available. The holder is aware of the provisions of Rule 144, promulgated under the Securities Act.

(4) The holder is an “accredited investor” as such term is defined in Rule 501 of Regulation D promulgated under the Securities Act.

(b) Disposition of Warrant or Shares. This warrant and any shares of Common Stock acquired pursuant to the exercise or conversion of this warrant may be transferred only pursuant to a registration statement filed under the Securities Act or an exemption from such

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registration. Subject to such restrictions, the Company shall transfer this warrant from time to time upon the books to be maintained by the Company for that purpose, upon surrender thereof for transfer properly endorsed or accompanied by appropriate instructions for transfer and such other documents as may be reasonably required by the Company, including, if required by the Company, an opinion of counsel to the effect that such transfer is exempt from the registration requirements of the Securities Act to establish that such transfer is being made in accordance with the terms hereof, and a new warrant shall be issued to the transferee and the surrendered warrant shall be cancelled by the Company. Each certificate representing this warrant or the shares of Common Stock thus transferred (except a transfer pursuant to Rule 144 or 144A) shall bear a legend as to the applicable restrictions on transferability in order to ensure compliance with such laws, unless such legend is not required in order to ensure compliance with such laws. The Company may issue stop transfer instructions to its transfer agent in connection with such restrictions.

(c) Applicability of Restrictions. Neither any restrictions of any legend described in this warrant nor the requirements of Section 7(b) above shall apply to any transfer of, or grant of a security interest in, this warrant (or the Common Stock obtainable upon exercise hereof) or any part hereof (i) to a partner of the holder if the holder is a partnership or to a member of the holder if the holder is a limited liability company, (ii) to a partnership of which the holder is a partner or to a limited liability company of which the holder is a member, or (iii) to any affiliate of the holder if the holder is a corporation; provided, however, in any such transfer, if applicable, the transferee shall on the Company’s request agree in writing to be bound by the terms of this warrant as if an original holder hereof.

8. Rights as Stockholders; Information. No holder of this warrant, as such, shall be entitled to vote or receive dividends or be deemed the holder of Common Stock issuable upon the exercise hereof for any purpose, nor shall anything contained herein be construed to confer upon the holder of this warrant, as such, any of the rights of a stockholder of the Company or any right to vote for the election of directors or upon any matter submitted to stockholders at any meeting thereof, or to receive notice of meetings, or to receive dividends or subscription rights or otherwise until this warrant shall have been exercised and the Shares purchasable upon the exercise hereof shall have become deliverable, as provided herein.

9. Right to Convert Warrant into Stock; Net Issuance.

(a) Right to Convert. In addition to and without limiting the rights of the holder under the terms of this warrant, the holder shall have the right to convert this warrant or any portion thereof (the “Conversion Right”) into shares of Common Stock as provided in this Section 9 at any time or from time to time during the term of this warrant. Upon exercise of the Conversion Right with respect to a particular number of shares subject to this warrant (the “Converted Warrant Shares”), the Company shall deliver to the holder (without payment by the holder of any exercise price or any cash or other consideration) that number of shares of fully paid and nonassessable Common Stock as is determined according to the following formula:

X = B - A

Y

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Where: X =	the number of shares of Common Stock that shall be issued to holder
Y =	the fair market value of one share of Common Stock
A =	the aggregate Warrant Price of the specified number of Converted Warrant Shares immediately prior to the exercise of the Conversion Right (i.e., the number of Converted Warrant Shares multiplied by the Warrant Price)
B =	the aggregate fair market value of the specified number of Converted Warrant Shares (i.e., the number of Converted Warrant Shares multiplied by the fair market value of one Converted Warrant Share)

No fractional shares shall be issuable upon exercise of the Conversion Right, and, if the number of shares to be issued determined in accordance with the foregoing formula is other than a whole number, the Company shall pay to the holder an amount in cash equal to the fair market value of the resulting fractional share on the Conversion Date (as hereinafter defined).

(b) Method of Exercise. The Conversion Right may be exercised by the holder by the surrender of this warrant at the principal office of the Company together with a written statement (which may be in the form of Exhibit A-1) specifying that the holder thereby intends to exercise the Conversion Right and indicating the number of shares subject to this warrant which are being surrendered (referred to in Section 9(a) hereof as the Converted Warrant Shares) in exercise of the Conversion Right. Such conversion shall be effective upon receipt by the Company of this warrant together with the aforesaid written statement, or on such later date as is specified therein (the “Conversion Date”). Certificates for the shares issuable upon exercise of the Conversion Right and, if applicable, a new warrant evidencing the balance of the shares remaining subject to this warrant, shall be issued as of the Conversion Date and shall be delivered to the holder within thirty (30) days following the Conversion Date.

(c) Determination of Fair Market Value. For purposes of this Section 9, “fair market value” of a share of Common Stock as of a particular date (the “Determination Date”) shall mean: (i) if traded on a securities exchange, the fair market value of the Common Stock shall be deemed to be the average of the closing prices of the Common Stock on such exchange over the five trading days immediately prior to the Determination Date as reported by Bloomberg Financial Markets (or a comparable reporting service of national reputation selected by the Company and reasonably acceptable to the holder if Bloomberg Financial Markets is not then reporting sales prices of such security) (collectively, “Bloomberg”); (ii) if traded on the Nasdaq Stock Market or other over-the-counter system, the fair market value of the Common Stock shall be deemed to be the average of the closing bid prices of the Common Stock over the five trading days immediately prior to the Determination Date as reported by Bloomberg; and (iii) if there is no public market for the Common Stock, then fair market value shall be determined by the Board of Directors of the Company in good faith.

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10. Representations and Warranties. The Company represents and warrants to the holder of this warrant as follows:

(a) This warrant has been duly authorized and executed by the Company and is a valid and binding obligation of the Company enforceable in accordance with its terms, subject to laws of general application relating to bankruptcy, insolvency and the relief of debtors and the rules of law or principles at equity governing specific performance, injunctive relief and other equitable remedies.

(b) The Shares have been duly authorized and reserved for issuance by the Company and, when issued in accordance with the terms hereof, will be validly issued, fully paid and nonassessable and free from preemptive rights.

(c) The execution and delivery of this warrant are not, and the issuance of the Shares upon exercise of this warrant in accordance with the terms hereof will not be, inconsistent with the Company’s certificate of incorporation or bylaws, do not and will not contravene any law, governmental rule or regulation, judgment or order applicable to the Company, and do not and will not conflict with or contravene any provision of, or constitute a default under, any indenture, mortgage, contract or other instrument of which the Company is a party or by which it is bound or require the consent or approval of, the giving of notice to, the registration or filing with or the taking of any action in respect of or by, any federal, state or local government authority or agency or other person, except for the filing of notices pursuant to federal and state securities laws, which filings will be effected by the time required thereby.

11. Modification and Waiver. This warrant and any provision hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of the same is sought.

12. Notices. Any notice, request, communication or other document required or permitted to be given or delivered to the holder hereof or the Company shall be delivered, or shall be sent by certified or registered mail, postage prepaid, to each such holder at its address as shown on the books of the Company or to the Company at the address indicated therefor on the signature page of this warrant.

13. Binding Effect on Successors. This warrant shall be binding upon any corporation succeeding the Company by merger, consolidation or acquisition of all or substantially all of the Company’s assets, and all of the obligations of the Company relating to the Common Stock issuable upon the exercise or conversion of this warrant shall survive the exercise, conversion and termination of this warrant and all of the covenants and agreements of the Company shall inure to the benefit of the successors and assigns of the holder hereof.

14. Lost Warrants or Stock Certificates. The Company covenants to the holder hereof that, upon receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this warrant or any stock certificate and, in the case of any such loss, theft or destruction, upon receipt of an indemnity reasonably satisfactory to the Company, or in the case of any such mutilation upon surrender and cancellation of such warrant or stock certificate, the Company will make and deliver a new warrant or stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or mutilated warrant or stock certificate.

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15. Descriptive Headings. The descriptive headings of the various sections of this warrant are inserted for convenience only and do not constitute a part of this warrant. The language in this warrant shall be construed as to its fair meaning without regard to which party drafted this warrant.

16. Governing Law. This warrant shall be construed and enforced in accordance with, and the rights of the parties shall be governed by, the laws of the State of California.

17. Remedies. In case any one or more of the covenants and agreements contained in this warrant shall have been breached, the holder hereof (in the case of a breach by the Company), or the Company (in the case of a breach by a holder), may proceed to protect and enforce their or its rights either by suit in equity and/or by action at law, including, but not limited to, an action for damages as a result of any such breach and/or an action for specific performance of any such covenant or agreement contained in this warrant.

18. No Impairment of Rights. The Company will not, by amendment of its certificate of incorporation or through any other means, avoid or seek to avoid the observance or performance of any of the terms of this warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the holder of this warrant against impairment.

19. Severability. The invalidity or unenforceability of any provision of this warrant in any jurisdiction shall not affect the validity or enforceability of such provision in any other jurisdiction, or affect any other provision of this warrant, which shall remain in full force and effect.

20. Recovery of Litigation Costs. If any legal action or other proceeding is brought for the enforcement of this warrant, or because of an alleged dispute, breach, default, or misrepresentation in connection with any of the provisions of this warrant, the successful or prevailing party or parties shall be entitled to recover reasonable attorneys’ fees and other costs incurred in that action or proceeding, in addition to any other relief to which it or they may be entitled.

21. Entire Agreement; Modification. This warrant constitutes the entire agreement between the parties pertaining to the subject matter contained in it and supersedes all prior and contemporaneous agreements, representations, and undertakings of the parties, whether oral or written, with respect to such subject matter.

(Signature page follows)

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The Company has caused this Warrant to Purchase Shares of Common Stock of Sunesis Pharmaceuticals, Inc. to be duly executed and delivered as of the Date of Grant specified above.

SUNESIS PHARMACEUTICALS, INC.
By:	/s/ Daryl B. Winter, Ph.D.
Name:	Daryl B. Winter
Title:	Sr. Vice President and General Counsel
Address:	341 Oyster Point Boulevard
	South San Francisco, CA 94080

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EXHIBIT A-1

NOTICE OF EXERCISE

To: SUNESIS PHARMACEUTICALS, INC. (the “Company”)

1. The undersigned hereby:

¨ elects to purchase              shares of common stock of the Company pursuant to the terms of the attached warrant, and tenders herewith payment of the purchase price of such shares in full, or

¨ elects to exercise its net issuance rights pursuant to Section 9 of the attached warrant with respect to              shares of common stock.

2. Please issue a certificate or certificates representing              shares in the name of the undersigned or in such other name or names as are specified below:

(Name)

(Address)

3. The undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in connection with, the distribution thereof and that the undersigned has no present intention of distributing or reselling such shares, all except as in compliance with applicable securities laws.

(Signature)

______________

        (Date)

EX-99.E

Exhibit E

REGISTRATION RIGHTS AGREEMENT

This Registration Rights Agreement (the “Agreement”) is made and entered into as of this 17^th day of March 2006 by and among Sunesis Pharmaceuticals, Inc., a Delaware corporation (the “Company”), and the “Investors” named in that certain Common Stock and Warrant Purchase Agreement, dated as of March 17, 2006 (the “Purchase Agreement”), by and among the Company and the Investors.

The parties hereby agree as follows:

1. Certain Definitions.

As used in this Agreement, the following terms shall have the following meanings:

“Affiliate” means, with respect to any Person, any other Person which directly or indirectly controls, is controlled by, or is under common control with, such Person.

“Business Day” means a day, other than a Saturday or Sunday, on which banks in New York City are open for the general transaction of business.

“Common Stock” shall mean the Company’s common stock, par value $0.0001 per share.

“Effectiveness Date” means the date on which the Registration Statement is declared effective by the SEC.

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

“Filing Date” means the date on which the Registration Statement is first filed with the SEC.

“Investor Rights Agreement” means the Eighth Amended and Restated Investor Rights Agreement, dated August 30, 2004, as amended, by and among the Company and the Persons listed on the signature pages thereto.

“Investors” shall mean the Investors identified in the Purchase Agreement and any Affiliate or permitted transferee of any Investor who is a subsequent holder of any Registrable Securities.

“Person” means an individual, corporation, partnership, limited liability company, trust, business trust, association, joint stock company, joint venture, sole proprietorship, unincorporated organization, governmental authority or any other form of entity not specifically listed herein.

“Prospectus” shall mean the prospectus included in any Registration Statement, as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Registrable Securities covered by such Registration Statement and by all other amendments and supplements to the prospectus, including post-effective amendments and all material incorporated by reference in such prospectus.

“Register,” “registered” and “registration” refer to a registration made by preparing and filing a Registration Statement or similar document in compliance with the Securities Act (as

defined below), and the declaration or ordering of effectiveness of such Registration Statement or document.

“Registrable Securities” shall mean (i) the Shares, (ii) the Warrant Shares and (iii) any other securities issued or issuable with respect to or in exchange for Shares and the Warrant Shares, including shares issued upon any stock split, stock dividend, recapitalization, subdivision or similar event, provided that a security shall cease to be a Registrable Security upon (A) sale pursuant to a Registration Statement or Rule 144 under the Securities Act or (B) such security becoming eligible for sale by the Investors pursuant to Rule 144(k).

“Registration Statement” shall mean any registration statement of the Company filed under the Securities Act that covers the resale of any of the Registrable Securities pursuant to the provisions of this Agreement, amendments and supplements to such Registration Statement, including post-effective amendments, all exhibits and all material incorporated by reference in such Registration Statement.

“Required Investors” means the Investors holding a majority of the Registrable Securities.

“SEC” means the Securities and Exchange Commission.

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

“Shares” means the shares of Common Stock issued pursuant to the Purchase Agreement.

“Warrant Shares” means the shares of Common Stock issuable upon exercise of the Warrants.

“Warrants” means the Warrants to Purchase Shares of Common Stock of Sunesis Pharmaceuticals, Inc. issued pursuant to the Purchase Agreement.

2. Registration.

(a) Registration Statement. As soon as reasonably practicable following the Closing (as defined in the Purchase Agreement but no later than thirty-five (35) days after the Closing (the “Filing Deadline”), the Company shall prepare and file with the SEC a Registration Statement on Form S-1 covering the resale of the Shares and the Warrant Shares. Such Registration Statement also shall cover to the extent allowable under the Securities Act and the rules promulgated thereunder, such indeterminate number of additional shares of Common Stock resulting from stock splits, stock dividends or similar transactions with respect to the Shares. The Registration Statement (and each amendment or supplement thereto, and each request for acceleration of effectiveness thereof) shall be provided in accordance with Section 3(c) to the Investors and their counsel prior to its filing or other submission. If a Registration Statement covering the Registrable Securities is not filed with the SEC on or prior to the Filing Deadline, the Company will make pro rata payments to each Investor, as liquidated damages and not as a penalty, in an amount equal to one percent (1.0%) of the aggregate amount invested by such Investor for each 30-day period or pro rata for any portion thereof following the Filing Deadline for which no Registration Statement is filed with respect to the Registrable Securities; provided, however, that the aggregate amount of such liquidated damages payable to each Investor, together with the amount of any liquidated damages previously paid pursuant to any

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provision of this Agreement, shall under no circumstances exceed ten percent (10.0%) of the aggregate amount invested by such Investor. Such payments shall be made to each Investor in cash.

(b) Expenses. The Company will pay all expenses associated with each registration, including filing and printing fees, the Company’s counsel and accounting fees and expenses, costs associated with clearing the Registrable Securities for sale under applicable state securities laws and listing fees, but excluding fees and expenses of counsel to the Investors, discounts, commissions, fees of underwriters, selling brokers, dealer managers or similar securities industry professionals with respect to the Registrable Securities being sold, provided that the Company shall pay the reasonable fees and expenses, not to exceed $5,000 in the aggregate, of one counsel for the Investors.

(c) Effectiveness.

(i) The Company shall use commercially reasonable efforts to have the Registration Statement declared effective as soon as practicable. The Company shall notify the Investors by facsimile or e-mail as promptly as practicable, and in any event, within twenty-four (24) hours, after any Registration Statement is declared effective and shall provide the Investors with copies of any related Prospectus to be used in connection with the sale or other disposition of the securities covered thereby. If a Registration Statement covering the Registrable Securities is not declared effective by the SEC within (i) thirty-five (35) days after the Filing Date if the SEC shall have informed the Company that no review of the Registration Statement will be made or (ii) 105 days after the Filing Date if the SEC shall have informed the Company that a review of the Registration Statement will be made, then the Company will make pro rata payments to each Investor, as liquidated damages and not as a penalty, in an amount equal to one percent (1.0%) of the aggregate amount invested by such Investor for each 30-day period or pro rata for any portion thereof following the date by which such Registration Statement should have been effective; provided, however, that the aggregate amount of such liquidated damages payable to each Investor, together with the amount of any liquidated damages previously paid pursuant to any provision of this Agreement, shall under no circumstances exceed ten percent (10.0%) of the aggregate amount invested by such Investor. Such payments shall be made to each Investor in cash.

(ii) After such time as the Company becomes eligible to file a registration statement on Form S-3, the Company shall file a post-effective amendment to the Registration Statement to provide for the automatic incorporation by reference of the Company’s reports subsequently filed pursuant to the Exchange Act.

(iii) Except as required by the provisions of the Investor Rights Agreement, the Company shall not file a registration statement on Form S-1 or S-3 until the Effectiveness Date.

3. Suspension.

(a) Subject to Section 3(b) below, in the event: (i) of any request by the SEC or any other federal or state governmental authority during the period of effectiveness of

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the Registration Statement for amendments or supplements to the Registration Statement or related prospectus or for additional information so that the Registration Statement will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading or otherwise fail to comply with the applicable rules and regulations of the federal securities laws; (ii) of the issuance by the SEC or any other federal or state governmental authority of any stop order suspending the effectiveness of the Registration Statement or the initiation of any proceedings for that purpose; (iii) of the receipt by the Company of any notification with respect to the suspension of the qualification or exemption from qualification of any of the Registrable Securities for sale in any jurisdiction or the initiation of any proceeding for such purpose, provided that, considering the advice of counsel, the Company reasonably believes that it must qualify in such jurisdiction; (iv) of any event or circumstance that, considering the advice of counsel, the Company reasonably believes necessitates the making of any changes in the Registration Statement or related prospectus, or any document incorporated or deemed to be incorporated therein by reference, so that, in the case of the Registration Statement, it will not contain any untrue statement of a material fact or any omission to state a material fact required to be stated therein or necessary to make the statements therein not misleading, and that in the case of a related prospectus, it will not contain any untrue statement of a material fact or any omission to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; or (v) that the Company reasonably believes, considering the advice of counsel, that the Company may, in the absence of a suspension described hereunder, be required under state or federal securities laws to disclose any corporate development, the disclosure of which could reasonably be expected to have a material adverse effect upon the Company, its stockholders, a potentially material transaction or event involving the Company, or any negotiations, discussions or proposals directly relating thereto; then the Company shall deliver a certificate in writing to each Holder of Registrable Securities (the “Suspension Notice”) to the effect of the foregoing (but in no event, without the prior written consent of an Investor, shall the Company disclose to such Investor any of the facts or circumstances regarding any material nonpublic information) and, upon receipt of such Suspension Notice, the Holder will refrain from selling any Registrable Securities pursuant to the Registration Statement (a “Suspension”) until the Holder’s receipt of copies of a supplemented or amended prospectus prepared and filed by the Company or until the Holder is advised in writing by the Company that the current prospectus may be used and the Holder has received copies of any additional or supplemental filings that are incorporated or deemed incorporated by reference in any such prospectus.

(b) Notwithstanding the foregoing, the Company shall not suspend any Registration Statement or related prospectus for more than thirty (30) consecutive days or for a total of not more than sixty (60) days in any twelve (12) month period (each a “Permitted Suspension” and together the “Permitted Suspensions”).

(c) On any day after the Effectiveness Date sales of all the Registrable Securities required to be included on such Registration Statement cannot be made pursuant to such Registration Statement (including, without limitation, because of a failure to keep such Registration Statement effective, to disclose such information as is necessary for sales to be made pursuant to such Registration Statement or to register sufficient shares of Registrable Securities or because of a Suspension) then the Company will make pro rata payments to each

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Investor, as liquidated damages and not as a penalty, in an amount equal to one percent (1.0%) of the aggregate amount invested by such Investor for each 30-day period or pro rata for any portion thereof following the date by which such sales of Registrable Securities under the Registration Statement cannot be made; provided, however, that the aggregate amount of such liquidated damages payable to each Investor, together with the amount of any liquidated damages previously paid pursuant to any provision of this Agreement, shall under no circumstances exceed ten percent (10.0%) of the aggregate amount invested by such Investor. Such payments shall be made to each Investor in cash. Notwithstanding the foregoing, the Company shall not be required to pay liquidated damages during any Permitted Suspension.

(d) The Company will use commercially reasonable efforts to terminate an Suspension as promptly as practicable after delivery of a Suspension Notice to the Holders.

4. Company Obligations. The Company will use commercially reasonable efforts to effect the registration of the Registrable Securities in accordance with the terms hereof, and pursuant thereto the Company will, as expeditiously as possible:

(a) use commercially reasonable efforts to cause such Registration Statement to become effective and to remain continuously effective for a period that will terminate upon the earlier of (i) the date on which all Registrable Securities have been sold pursuant to the Registration Statement, as amended from time to time, (ii) the date on which all Registrable Securities covered by such Registration Statement may be sold pursuant to Rule 144 in a three-month period and (iii) the two-year anniversary of the Effectiveness Date (the “Effectiveness Period”) and advise the Investors in writing when the Effectiveness Period has expired;

(b) prepare and file with the SEC such amendments and post-effective amendments to the Registration Statement and such supplements to the Prospectus as may be necessary to keep the Registration Statement effective for the period specified in Section 4(a) and to comply with the provisions of the Securities Act and the Exchange Act with respect to the distribution of all of the Registrable Securities covered thereby;

(c) provide copies to and permit counsel designated by the Investors to review the Registration Statement and any amendments or supplements thereto and any comments made by the staff of the SEC and the Company’s responses thereto a reasonable period of time prior to its filing with the SEC or its receipt from the SEC as applicable and shall duly consider comments made by such counsel thereon;

(d) furnish to the Investors and their legal counsel (i) promptly after the same is prepared and publicly distributed, filed with the SEC, or received by the Company (but not later than two (2) Business Days after the filing date, receipt date or sending date, as the case may be) one (1) copy of any Registration Statement and any amendment thereto, each preliminary prospectus and Prospectus and each amendment or supplement thereto, and each letter written by or on behalf of the Company to the SEC or the staff of the SEC, and each item of correspondence from the SEC or the staff of the SEC, in each case relating to such Registration Statement (other than any portion of any thereof which contains information for

5

which the Company has sought confidential treatment), and (ii) an electronic copy of a Prospectus, including a preliminary prospectus, and all amendments and supplements thereto and such other documents as each Investor may reasonably request in connection with the disposition of the Registrable Securities owned by such Investor that are covered by the related Registration Statement;

(e) use commercially reasonable efforts to (i) prevent the issuance of any stop order or other suspension of effectiveness and, (ii) if such order is issued, obtain the withdrawal of any such order at the earliest practicable time and to notify each Investor of the issuance of such an order and the resolution thereof;

(f) prior to any public offering of Registrable Securities, use commercially reasonable efforts to register or qualify or cooperate with the Investors and their counsel in connection with the registration or qualification of such Registrable Securities for offer and sale under the securities or blue sky laws of such jurisdictions requested by the Investors and do any and all other commercially reasonable acts or things necessary or advisable to enable the distribution in such jurisdictions of the Registrable Securities covered by the Registration Statement; provided, however, that the Company shall not be required in connection therewith or as a condition thereto to (i) qualify to do business in any jurisdiction where it would not otherwise be required to qualify but for this Section 3(f), (ii) subject itself to general taxation in any jurisdiction where it would not otherwise be so subject but for this Section 3(f), or (iii) file a general consent to service of process in any such jurisdiction;

(g) use commercially reasonable efforts to cause all Registrable Securities covered by a Registration Statement to be listed on each securities exchange, interdealer quotation system or other market on which similar securities issued by the Company are then listed;

(h) immediately notify the Investors, at any time when a Prospectus relating to Registrable Securities is required to be delivered under the Securities Act, upon discovery that, or upon the happening of any event as a result of which, the Prospectus included in a Registration Statement, as then in effect, includes an untrue statement of a material fact or omits to state any material fact required to be stated therein or necessary to make the statements therein not misleading in light of the circumstances then existing, and at the request of any such holder, promptly prepare and furnish to such holder an electronic copy of a supplement to or an amendment of such Prospectus as may be necessary so that, as thereafter delivered to the purchasers of such Registrable Securities, such Prospectus shall not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading in light of the circumstances then existing;

(i) otherwise use commercially reasonable efforts to comply with all applicable rules and regulations of the SEC under the Securities Act and the Exchange Act, take such other actions as may be reasonably necessary to facilitate the registration of the Registrable Securities hereunder; and make available to its security holders, as soon as reasonably practicable, but not later than the Availability Date (as defined below), an earnings statement covering a period of at least twelve (12) months, beginning after the effective date of each Registration Statement, which earnings statement shall satisfy the provisions of Section 11(a) of

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the Securities Act, including Rule 158 promulgated thereunder (for the purpose of this subsection 3(i), “Availability Date” means the 45th day following the end of the fourth fiscal quarter that includes the effective date of such Registration Statement, except that, if such fourth fiscal quarter is the last quarter of the Company’s fiscal year, “Availability Date” means the 90th day after the end of such fourth fiscal quarter); and

(j) with a view to making available to the Investors the benefits of Rule 144 (or its successor rule) and any other rule or regulation of the SEC that may at any time permit the Investors to sell shares of Common Stock to the public without registration, the Company covenants and agrees to: (i) make and keep public information available, as those terms are understood and defined in Rule 144, during the Effectiveness Period; (ii) file with the SEC in a timely manner all reports and other documents required of the Company under the Exchange Act; and (iii) furnish to each Investor upon request, as long as such Investor owns any Registrable Securities, (A) a written statement by the Company that it has complied with the reporting requirements of the Exchange Act, (B) a copy of the Company’s most recent Annual Report on Form 10-K or Quarterly Report on Form 10-Q, and (C) such other information as may be reasonably requested in order to avail such Investor of any rule or regulation of the SEC that permits the selling of any such Registrable Securities without registration.

5. Obligations of the Investors.

(a) Each Investor shall furnish in writing to the Company such information regarding itself, the Registrable Securities held by it and the intended method of disposition of the Registrable Securities held by it, as shall be required to effect the registration of such Registrable Securities and shall execute such documents in connection with such registration as the Company may reasonably request. At least five (5) Business Days prior to the first anticipated filing date of any Registration Statement, the Company shall notify each Investor of the information the Company requires from such Investor if such Investor elects to have any of the Registrable Securities included in the Registration Statement. An Investor shall provide such information to the Company at least two (2) Business Days prior to the first anticipated filing date of such Registration Statement if such Investor elects to have any of the Registrable Securities included in the Registration Statement.

(b) Each Investor, by its acceptance of the Registrable Securities agrees to cooperate with the Company as reasonably requested by the Company in connection with the preparation and filing of a Registration Statement hereunder, unless such Investor has notified the Company in writing of its election to exclude all of its Registrable Securities from such Registration Statement.

(c) Each Investor agrees that, upon receipt of any notice from the Company of either (i) the commencement of an Suspension pursuant to Section 3, such Investor will immediately discontinue disposition of Registrable Securities pursuant to the Registration Statement covering such Registrable Securities, until the Investor’s receipt of the supplemented or amended prospectus filed with the SEC and until any related post-effective amendment is declared effective and, if so directed by the Company, the Investor shall deliver to the Company (at the expense of the Company) or destroy (and deliver to the Company a certificate of

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destruction) all copies in the Investor’s possession of the Prospectus covering the Registrable Securities current at the time of receipt of such notice.

6. Indemnification.

(a) Indemnification by the Company. The Company agrees to indemnify and hold harmless, to the fullest extent permitted by law, the Investors and their respective directors, officers, employees, stockholders and each Person who controls any Investor (within the meaning of the Securities Act) against any losses, claims, damages, liabilities and expense (including reasonable attorney fees) resulting from or which arise out of or are based up any untrue statement or alleged untrue statement of a material fact or any omission or alleged omission of a material fact required to be stated in the Registration Statement or Prospectus or preliminary prospectus or amendment or supplement thereto or necessary to make the statements therein not misleading and will reimburse each Investor and their respective directors, officers, employees, stockholders or controlling Persons for any legal and other expenses reasonably incurred as such expenses are reasonably incurred by such Person in connection with investigating, defending, settling, compromising or paying any such loss, claim, damage, liability, expense or action; provided, however, that the Company will not be liable in any such case if and to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission so made in conformity with information furnished by an Investor in writing specifically for use in such Registration Statement or Prospectus.

(b) Indemnification by the Investors. Each Investor agrees, severally but not jointly, to indemnify and hold harmless, to the fullest extent permitted by law, the Company, its directors, officers, employees, stockholders and each Person who controls the Company (within the meaning of the Securities Act) against any losses, claims, damages, liabilities and expense (including reasonable attorney fees) resulting from or which arise out of or are based upon any untrue statement or alleged untrue statement of a material fact or any omission or alleged omission of a material fact required to be stated in the Registration Statement or Prospectus or preliminary prospectus or amendment or supplement thereto or necessary to make the statements therein not misleading, to the extent, but only to the extent that such untrue statement or omission or alleged statement or omission is contained in any information furnished in writing by such Investor to the Company specifically for inclusion in such Registration Statement or Prospectus or amendment or supplement thereto, and will reimburse the Company and its directors, officers, employees, stockholders or controlling Persons for any legal and other expenses reasonably incurred as such expenses are reasonably incurred by such Person in connection with investigating, defending, settling, compromising or paying any such loss, claim, damage, liability, expense or action. In no event shall the liability of an Investor be greater in amount than the dollar amount of the proceeds (net of all expense paid by such Investor in connection with any claim relating to this Section 6 and the amount of any damages such Investor has otherwise been required to pay by reason of such untrue statement or omission or alleged untrue statement or omission) received by such Investor upon the sale of the Registrable Securities included in the Registration Statement giving rise to such indemnification obligation.

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(c) Conduct of Indemnification Proceedings. Any Person entitled to indemnification hereunder shall (i) give prompt notice to the indemnifying party of any claim with respect to which it seeks indemnification and (ii) permit such indemnifying party to assume the defense of such claim with counsel reasonably satisfactory to the indemnified party; provided that any Person entitled to indemnification hereunder shall have the right to employ separate counsel and to participate in the defense of such claim, but the fees and expenses of such counsel shall be at the expense of such Person unless (a) the indemnifying party has agreed to pay such fees or expenses, or (b) the indemnifying party shall have failed to assume the defense of such claim within five (5) Business Days after written notice thereof and employ counsel reasonably satisfactory to such Person or (c) in the reasonable judgment of any such Person, considering the advice of counsel, a conflict of interest exists between such Person and the indemnifying party with respect to such claims (in which case, if the Person notifies the indemnifying party in writing that such Person elects to employ separate counsel at the expense of the indemnifying party, the indemnifying party shall not have the right to assume the defense of such claim on behalf of such Person); and provided, further, that the failure of any indemnified party to give notice as provided herein shall not relieve the indemnifying party of its obligations hereunder, except to the extent that such failure to give notice shall materially adversely affect the indemnifying party in the defense of any such claim or litigation. It is understood that the indemnifying party shall not, in connection with any proceeding in the same jurisdiction, be liable for fees or expenses of more than one additional firm of attorneys at any time for all such indemnified parties. No indemnifying party will, except with the consent of the indemnified party, consent to entry of any judgment or enter into any settlement that does not include as an unconditional term thereof the giving by the claimant or plaintiff to such indemnified party of a release from all liability in respect of such claim or litigation.

(d) Contribution. If for any reason the indemnification provided for in the preceding paragraphs (a) and (b) is unavailable to an indemnified party or insufficient to hold it harmless, other than as expressly specified therein, then the indemnifying party shall contribute to the amount paid or payable by the indemnified party as a result of such loss, claim, damage or liability in such proportion as is appropriate to reflect the relative fault of the indemnified party and the indemnifying party, as well as any other relevant equitable considerations. No Person guilty of fraudulent misrepresentation within the meaning of Section 11(f) of the Securities Act shall be entitled to contribution from any Person not guilty of such fraudulent misrepresentation. In no event shall the contribution obligation of a holder of Registrable Securities be greater in amount than the dollar amount of the proceeds (net of all expenses paid by such holder in connection with any claim relating to this Section 6 and the amount of any damages such holder has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission) received by it upon the sale of the Registrable Securities giving rise to such contribution obligation.

7. Miscellaneous.

(a) Amendments and Waivers. This Agreement may be amended only by a writing signed by the Company and the Required Investors, provided that any such amendment shall not disproportionately affect the rights of any Investor, relative to all other Investors, without the consent of such Investor. The Company may take any action herein prohibited, or omit to perform any act herein required to be performed by it, only if the

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Company shall have obtained the written consent to such amendment, action or omission to act, of the Required Investors.

(b) Notices. All notices and other communications provided for or permitted hereunder shall be made as set forth in Section 9.4 of the Purchase Agreement.

(c) Assignments and Transfers by Investors. The provisions of this Agreement shall be binding upon and inure to the benefit of the Investors and their respective successors and assigns. An Investor may transfer or assign, in whole or from time to time in part, to one or more Persons its rights hereunder in connection with the transfer of Registrable Securities by such Investor to such Person, provided that such Investor complies with all laws applicable thereto and provides written notice of assignment to the Company promptly after such assignment is effected.

(d) Assignments and Transfers by the Company. This Agreement may not be assigned by the Company (whether by operation of law or otherwise) without the prior written consent of the Required Investors, provided, however, that the Company may assign its rights and delegate its duties hereunder to any surviving or successor corporation in connection with a merger or consolidation of the Company with another corporation, or a sale, transfer or other disposition of all or substantially all of the Company’s assets to another corporation, without the prior written consent of the Required Investors, after notice duly given by the Company to each Investor.

(e) Benefits of the Agreement. The terms and conditions of this Agreement shall inure to the benefit of and be binding upon the respective permitted successors and assigns of the parties. Nothing in this Agreement, express or implied, is intended to confer upon any party other than the parties hereto or their respective successors and assigns any rights, remedies, obligations, or liabilities under or by reason of this Agreement, except as expressly provided in this Agreement.

(f) Counterparts; Faxes. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. This Agreement may also be executed via facsimile, which shall be deemed an original.

(g) Titles and Subtitles. The titles and subtitles used in this Agreement are used for convenience only and are not to be considered in construing or interpreting this Agreement.

(h) Severability. Any provision of this Agreement that is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof but shall be interpreted as if it were written so as to be enforceable to the maximum extent permitted by applicable law, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction. To the extent permitted by applicable law, the parties hereby waive any provision of law which renders any provisions hereof prohibited or unenforceable in any respect.

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(i) Further Assurances. The parties shall execute and deliver all such further instruments and documents and take all such other actions as may reasonably be required to carry out the transactions contemplated hereby and to evidence the fulfillment of the agreements herein contained.

(j) Entire Agreement. This Agreement is intended by the parties as a final expression of their agreement and intended to be a complete and exclusive statement of the agreement and understanding of the parties hereto in respect of the subject matter contained herein. This Agreement supersedes all prior agreements and understandings between the parties with respect to such subject matter.

(k) Governing Law; Consent to Jurisdiction; Waiver of Jury Trial. This Agreement shall be governed by, and construed in accordance with, the internal laws of the State of California without regard to the choice of law principles thereof. Each of the parties hereto irrevocably submits to the exclusive jurisdiction of the courts of the State of California located in San Mateo County and the United States District Court for the Northern District of California for the purpose of any suit, action, proceeding or judgment relating to or arising out of this Agreement and the transactions contemplated hereby. Service of process in connection with any such suit, action or proceeding may be served on each party hereto anywhere in the world by the same methods as are specified for the giving of notices under this Agreement. Each of the parties hereto irrevocably consents to the jurisdiction of any such court in any such suit, action or proceeding and to the laying of venue in such court. Each party hereto irrevocably waives any objection to the laying of venue of any such suit, action or proceeding brought in such courts and irrevocably waives any claim that any such suit, action or proceeding brought in any such court has been brought in an inconvenient forum. EACH OF THE PARTIES HERETO WAIVES ANY RIGHT TO REQUEST A TRIAL BY JURY IN ANY LITIGATION WITH RESPECT TO THIS AGREEMENT AND REPRESENTS THAT COUNSEL HAS BEEN CONSULTED SPECIFICALLY AS TO THIS WAIVER.

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IN WITNESS WHEREOF, the parties have executed this Registration Rights Agreement as of the date first above written.

The Company:	SUNESIS PHARMACEUTICALS, INC.
	By:	/s/ Daniel N. Swisher, Jr.
	Name:	Daniel N. Swisher, Jr.
	Title:	President and Chief Executive Officer

The Investors:	ABINGWORTH BIOEQUITIES MASTER FUND LTD.
	BY:	Its Manager, Abingworth Management
	By:	/s/ James Abell
	Name:	James Abell
	Title:	Director

ALTA BIOPHARMA PARTNERS III, L.P.
BY:	ALTA BIOPHARMA MANAGEMENT III, LLC
By:	/s/ Hilary Strain
Name:	Hilary Strain
Title:	Vice President, Finance and Administration

Alta BioPharma Partners III GmbH & Co. Beteiligungs KG
BY:	ALTA BIOPHARMA MANAGEMENT III, LLC
By:	/s/ Hilary Strain
Name:	Hilary Strain
Title:	Vice President, Finance and Administration

ALTA EMBARCADERO BIOPHARMA PARTNERS III, LLC
By:	/s/ Hilary Strain
Name:	Hilary Strain
Title:	Vice President, Finance and Administration

The Investors:	BIOTECHNOLOGY VALUE FUND, L.P.
	By:	/s/ Mark Lambert
	Name:	Mark Lambert
	Title:	President of BVF Inc.
		General Partner of BVF Partners L.P.
		General Partner of Biotechnology Value Fund, L.P.

BIOTECHNOLOGY VALUE FUND II, L.P.
By:	/s/ Mark Lambert
Name:	Mark Lambert
Title:	President of BVF Inc.
	General Partner of BVF Partners L.P.
	General Partner of Biotechnology Value Fund, L.P.

INVESTMENT 10, L.L.C.
By:	/s/ Mark Lambert
Name:	Mark Lambert
Title:	President of BVF Inc.
	General Partner of BVF Partners L.P.
	General Partner of Biotechnology Value Fund, L.P.

BVF INVESTMENTS, L.L.C.
By:	/s/ Mark Lambert
Name:	Mark Lambert
Title:	President of BVF Inc.
	General Partner of BVF Partners L.P.
	General Partner of Biotechnology Value Fund, L.P.

The Investors:	DOMAIN PUBLIC EQUITY PARTNERS, L.P.
	BY:	Domain Public Equity Associates, L.L.C.
	By:	/s/ Nicole Vitullo
	Name:	Nicole Vitullo
	Title:	Managing Member

The Investors:	THE BOARD OF TRUSTEES OF THE LELAND
	STANFORD JUNIOR UNIVERSITY (SBST)
	By:	/s/ Martina S. Poquet
	Name:	Martina S. Poquet
	Title:	Director, Separate Investments Division

The Investors:	Warburg, Pincus Equity Partners, L.P.
	By:	Warburg Pincus Partners, LLC, its General Partner
	By:	Warburg, Pincus & Co., its Managing Member
	By:	/s/ Jonathan Leff
	Name:	Jonathan Leff
	Title:	Partner
	Warburg, Pincus Netherlands Equity Partners I, C.V.
	By:	Warburg Pincus Partners, LLC, its General Partner
	By:	Warburg, Pincus & Co., its Managing Member
	By:	/s/ Jonathan Leff
	Name:	Jonathan Leff
	Title:	Partner
	Warburg, Pincus Netherlands Equity Partners III, C.V.
	By:	Warburg Pincus Partners, LLC, its General Partner
	By:	Warburg, Pincus & Co., its Managing Member
	By:	/s/ Jonathan Leff
	Name:	Jonathan Leff
	Title:	Partner

The Investors:	Deerfield Special Situations Fund International, Ltd.
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO
	Deerfield Special Situations Fund, L.P.
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO
	Deerfield Partners, L.P.
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO
	Deerfield International Limited
	By:	/s/ Darren Levine
	Name:	Darren Levine
	Title:	CFO

The Investors:	Baker Bros. Investments, L.P.
	BY:	Baker Bros. Capital, L.P. (general partner)
	BY:	Baker Bros. Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member
	Baker Bros. Investments II, L.P.
	BY:	Baker Bros. Capital, L.P. (general partner)
	BY:	Baker Bros. Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member
	Baker Biotech Fund I, L.P.
	BY:	Baker Bros. Capital, L.P. (general partner)
	BY:	Baker Bros. Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member
	Baker Biotech Fund II, L.P.
	BY:	Baker Bros. Capital II, L.P. (general partner)
	BY:	Baker Bros. Capital II (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member
	Baker Biotech Fund II (Z), L.P.
	BY:	Baker Bros. Capital II (Z), L.P. (general partner)
	BY:	Baker Bros. Capital II (Z) (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

The Investors:	Baker Biotech Fund III, L.P.
	BY:	Baker Bros. Capital III, L.P. (general partner)
	BY:	Baker Bros. Capital III (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member
	Baker Biotech Fund III (Z), L.P.
	BY:	Baker Bros. Capital III (Z), L.P. (general partner)
	BY:	Baker Bros. Capital III (Z) (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member
	14159, L.P.
	BY:	14159 Capital, L.P. (general partner)
	BY:	14159 Capital (GP), LLC (general partner)
	By:	/s/ Julian Baker
	Name:	Julian Baker
	Title:	Managing Member

EX-99.F

Exhibit F

LOCK-UP LETTER AGREEMENT

Sunesis Pharmaceuticals, Inc.

341 Oyster Point Boulevard

South San Francisco, California 94080

Ladies and Gentlemen:

The undersigned understands that Sunesis Pharmaceuticals, Inc., a Delaware corporation (the “Company”), and certain persons (the “Investors”) propose to enter into a Common Stock and Warrant Purchase Agreement (the “Purchase Agreement”) providing for the purchase by the Investor of shares (the “Shares”) of Common Stock, par value $0.0001 per share (the “Common Stock”), of the Company and warrants (the “Warrants”) to purchase additional shares of Common Stock (the “Financing”).

In consideration of the execution of the Purchase Agreement by the Investors, and for other good and valuable consideration, the undersigned hereby irrevocably agrees that, without the prior written consent of the Company, the undersigned will not, directly or indirectly, (1) offer for sale, sell, pledge, or otherwise dispose of (or enter into any transaction or device that is designed to, or could be expected to, result in the disposition by any person at any time in the future of) any shares of Common Stock (including, without limitation, shares of Common Stock that may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”) and shares of Common Stock that may be issued upon exercise of any option or warrant) or securities convertible into or exchangeable for Common Stock, or (2) enter into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic benefits or risks of ownership of shares of Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or other securities, in cash or otherwise, for a period of 60 days after the Closing Date (as defined in the Purchase Agreement) (such 60-day period, the “Lock-Up Period”).

The foregoing paragraph shall not apply to (1) transfers of Common Stock or securities convertible into or exchangeable or exercisable for any shares of Common Stock made as a bona fide gift or gifts, provided that the donee or donees thereof agree in writing to be bound by the terms of this Lock-Up Letter Agreement prior to such transfer, (2) transfers of Common Stock or securities convertible into or exchangeable or exercisable for any shares of Common Stock to an immediate family member of the undersigned or to any trust for the direct or indirect benefit of the undersigned or an immediate family member of the undersigned, provided that the transferee agrees in writing to be bound by the terms of this Lock-Up Letter Agreement prior to such transfer and (3) distributions to partners, members, shareholders or affiliates of the undersigned, provided that the undersigned is a limited partnership, limited liability company or corporation and the distributees thereof agree in writing to be bound by the terms of this Lock-Up Letter Agreement prior to such distribution.

Notwithstanding the foregoing, if the registration statement covering the resale of the Shares and the shares of Common Stock issuable upon exercise of the Warrants (the “Registration Statement”) has not been declared effective by the SEC prior to the expiration of the Lock-Up Period, then the restrictions imposed by this Lock-Up Letter Agreement shall continue to apply until the earlier of the expiration of (1) the 30-day period beginning on the date that the Registration Statement is declared effective by the SEC or (2) the 180-day period after the Closing Date, unless the Company waives, in writing, such extension.

In furtherance of the foregoing, the Company and its transfer agent are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Lock-Up Letter Agreement.

It is understood that, if the Company notifies the Investors that it does not intend to proceed with the Financing, if the Purchase Agreement does not become effective, or if the Purchase Agreement (other than the provisions thereof that survive termination) shall terminate or be terminated prior to payment for and delivery of the Shares and the Warrants, the undersigned shall have no further obligations under this Lock-Up Letter Agreement.

The undersigned understands that the Company and the Investors will proceed with the Financing in reliance on this Lock-Up Letter Agreement. Whether or not the Financing actually occurs depends on a number of factors, including market conditions.

The terms of this Lock-Up Letter Agreement shall be construed in accordance with the laws of the State of California.

[Signature Page Follows]

Exhibit F

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Lock-Up Letter Agreement and that, upon request, the undersigned will execute any additional documents necessary in connection with the enforcement hereof. Any obligations of the undersigned shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned.

Very truly yours,
Warburg Pincus Equity Partners L.P.
Warburg Pincus Netherlands Equity Partners I
Warburg Pincus Netherlands Equity Partners II
Warburg Pincus Netherlands Equity Partners III
By:	Warburg Pincus, Its General Partner
/s/ Jonathan Leff
(Name of Signatory if Stockholder is an entity—Please Print)
(Title of Signatory if Stockholder is an entity—Please Print)

Dated: 3/14/06