SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13G

(Rule 13d-102)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO RULES 13d-1(b) (c), AND (d) AND AMENDMENTS THERETO FILED

PURSUANT TO RULE 13d-2

(Amendment No. 1)*

Infinity Pharmaceuticals, Inc.

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

45665G303

(CUSIP Number)

December 31, 2007

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

¨ Rule 13d-1(b)

¨ Rule 13d-1(c)

x Rule 13d-1(d)

*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 the disclosures provided in a prior cover page.

The information required in 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 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).

CUSIP No. 45665G303 13G Page 2 of 5 Pages

1.	NAMES OF REPORTING PERSONS Amgen Inc.
2.	CHECK THE APPROPRIATE BOX IF MEMBER OF A GROUP (see instructions) (a)  ¨ (b)  ¨
3.	SEC USE ONLY
4.	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware

NUMBER OF   SHARES   BENEFICIALLY   OWNED BY   EACH   REPORTING   PERSON   WITH	5.    SOLE VOTING POWER          1,447,499
	6.    SHARED VOTING POWER          -0-
	7.    SOLE DISPOSITIVE POWER          1,447,499
	8.    SHARED DISPOSITIVE POWER          -0-

9.	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,447,499
10.	CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9 7.4%
12.	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS) CO

CUSIP No. 45665G303 13G Page 3 of 5 Pages

Item 1(a).	Name of Issuer: Infinity Pharmaceuticals, Inc.
Item 1(b).	Address of Issuer’s Principal Executive Offices: 780 Memorial Drive Cambridge, MA 02139
Item 2(a).	Name of Person Filing: Amgen Inc.
Item 2(b).	Address of Principal Business Office or, if none, Residence: One Amgen Center Drive Thousand Oaks, CA 91320-1799
Item 2(c).	Citizenship: Delaware
Item 2(d).	Title of Class of Securities: Common stock, par value $0.001 per share
Item 2(e).	CUSIP Number: 45665G303
Item 3.	Not applicable.
Item 4.	Ownership. (a)    Amount beneficially owned: 1,447,499

CUSIP No. 45665G303 13G Page 4 of 5 Pages

	(b) Percent of class: Amgen Inc. may be deemed to be the beneficial owner of 7.4% of the outstanding shares of the Common Stock of Infinity Pharmaceuticals, Inc. based on the number of shares of the Common Stock shown as outstanding as of September 30, 2007 on the Form 10-Q filed by Infinity Pharmaceuticals, Inc. on November 7, 2007. (c)    Number of shares as to which such person has:
	(i)     Sole power to vote or to direct the vote                              1,447,499
	(ii)    Shared power to vote or to direct the vote                          -0-
	(iii)  Sole power to dispose or to direct the disposition of          1,447,499
	(iv)   Shared power to dispose or to direct the disposition of      -0-
Item 5.	Ownership of Five Percent or Less of a Class. Not applicable.
Item 6.	Ownership of More than Five Percent on Behalf of Another Person. Not applicable.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person. Not applicable.
Item 8.	Identification and Classification of Members of the Group. Not applicable.
Item 9.	Notice of Dissolution of Group. Not applicable.
Item 10.	Certifications. Not Applicable

CUSIP No. 45665G303 13G Page 5 of 5 Pages

SIGNATURE

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

Date: February 14, 2008 AMGEN INC.
By:	/s/ David J. Scott
	Name:	David J. Scott
	Title:	Senior Vice President, General Counsel and Secretary