SC 13D/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO

§ 240.13d-2(a)

(Amendment No. 5)¹

Rain Therapeutics Inc.

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

75082Q105

(CUSIP Number)

JAMES KRATKY

BVF PARTNERS L.P.

44 Montgomery St., 40th Floor

San Francisco, California 94104

(415) 525-8890

KENNETH A. SCHLESINGER, ESQ.

OLSHAN FROME WOLOSKY LLP

1325 Avenue of the Americas

New York, New York 10019

(212) 451-2300

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

November 8, 2022

(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 § 240.13d-7 for other parties to whom copies are to be sent.

1              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).

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BIOTECHNOLOGY VALUE FUND, L.P.
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			WC
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			DELAWARE
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					1,734,960
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					1,734,960
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			1,734,960
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			7.0%
	14	TYPE OF REPORTING PERSON
			PN

2

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BVF I GP LLC
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			AF
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			DELAWARE
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					1,734,960
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					1,734,960
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			1,734,960
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			7.0%
	14	TYPE OF REPORTING PERSON
			OO

3

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BIOTECHNOLOGY VALUE FUND II, L.P.
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			WC
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			DELAWARE
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					1,367,838
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					1,367,838
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			1,367,838
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			5.5%
	14	TYPE OF REPORTING PERSON
			PN

4

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BVF II GP LLC
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			AF
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			DELAWARE
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					1,367,838
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					1,367,838
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			1,367,838
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			5.5%
	14	TYPE OF REPORTING PERSON
			OO

5

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BIOTECHNOLOGY VALUE TRADING FUND OS, L.P.
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			WC
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			CAYMAN ISLANDS
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					185,388
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					185,388
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			185,388
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			Less than 1%
	14	TYPE OF REPORTING PERSON
			PN

6

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BVF PARTNERS OS LTD.
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			AF
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			CAYMAN ISLANDS
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					185,388
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					185,388
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			185,388
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			Less than 1%
	14	TYPE OF REPORTING PERSON
			CO

7

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BVF GP Holdings LLC
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			AF
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			DELAWARE
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					3,102,798
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					3,102,798
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			3,102,798
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			12.5%
	14	TYPE OF REPORTING PERSON
			OO

8

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BVF PARTNERS L.P.
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			AF
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			DELAWARE
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					3,526,729
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					3,526,729
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			3,526,729
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			14.2%
	14	TYPE OF REPORTING PERSON
			PN, IA

9

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			BVF INC.
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			AF
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			DELAWARE
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					3,526,729
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					3,526,729
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			3,526,729
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			14.2%
	14	TYPE OF REPORTING PERSON
			CO

10

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			MARK N. LAMPERT
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
			AF
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			USA
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					3,526,729
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					3,526,729
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			3,526,729
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			14.2%
	14	TYPE OF REPORTING PERSON
			IN

11

CUSIP No. 75082Q105

	1	NAME OF REPORTING PERSON
			Gorjan Hrustanovic
	2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP				(a) ☒
						(b) ☐
	3	SEC USE ONLY
	4	SOURCE OF FUNDS
	5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) OR 2(e)				☐
	6	CITIZENSHIP OR PLACE OF ORGANIZATION
			USA
NUMBER OF			7	SOLE VOTING POWER
SHARES
BENEFICIALLY					- 0 -
OWNED BY			8	SHARED VOTING POWER
EACH
REPORTING					- 0 -
PERSON WITH			9	SOLE DISPOSITIVE POWER
					- 0 -
			10	SHARED DISPOSITIVE POWER
					- 0 -
	11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
			- 0 -
	12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES				☐
	13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
			0%
	14	TYPE OF REPORTING PERSON
			IN

12

CUSIP No. 75082Q105

The following constitutes Amendment No. 5 to the Schedule 13D filed by the undersigned (“Amendment No. 5”). This Amendment No. 5 amends the Schedule 13D as specifically set forth herein.

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

Item 3 is hereby amended and restated to read as follows:

The Shares beneficially owned by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Accounts were purchased with working capital (which may, at any given time, include margin loans made by brokerage firms in the ordinary course of business) in open market purchases, except as otherwise noted.

The aggregate purchase price of the Shares beneficially owned by BVF is approximately $26,039,412, including brokerage commissions. The aggregate purchase price of the Shares beneficially owned by BVF2 is approximately $20,229,292, including brokerage commissions. The aggregate purchase price of the Shares beneficially owned by Trading Fund OS is approximately $2,782,270, including brokerage commissions. The aggregate purchase price of the Shares held in the Partners Managed Accounts is approximately $1,925,390, including brokerage commissions.

The aggregate purchase price of the non-voting common stock directly owned by BVF is approximately $16,532,282, including brokerage commissions. The aggregate purchase price of the non-voting common stock directly owned by BVF2 is approximately $11,935,281, including brokerage commissions. The aggregate purchase price of the non-voting common stock directly owned by Trading Fund OS is approximately $1,960,944, including brokerage commissions. The aggregate purchase price of the non-voting common stock held in the Partners Managed Accounts is approximately $28,520, including brokerage commissions.

Pursuant to a certain agreement entered into between Partners and Dr. Hrustanovic, Dr. Hrustanovic is obligated to transfer the economic benefit, if any, received upon the sale of any Shares issuable upon the exercise of options granted to Dr. Hrustanovic in his capacity as a director of the Issuer. As of the date hereof, Dr. Hrustanovic does not beneficially own any Shares.

Item 5. Interest in Securities of the Issuer.

Items 5(a) – (c) are hereby amended and restated to read as follows:

(a) The aggregate percentage of Shares reported owned by each person named herein is based on 24,763,488 Shares outstanding as of November 8, 2022, which is the total number of Shares outstanding following the close of the Issuer’s public offering as disclosed in the Issuer’s Prospectus filed with the Securities and Exchange Commission on November 7, 2022.

As of the date hereof, BVF beneficially owns, subject to the Beneficial Ownership Limitation (as defined in Item 4 of the Schedule 13D), 2,870,985 shares of non-voting common stock and 1,734,960 Shares. As of the date hereof, the Beneficial Ownership Limitation limits the aggregate conversion of the non-voting common stock by BVF to 0 out of the 2,870,985 Shares underlying the non-voting common stock, resulting in percentage beneficial ownership of approximately 7.0% of the outstanding Shares.

As of the date hereof, BVF2 beneficially owns, subject to the Beneficial Ownership Limitation, 2,076,085 shares of non-voting common stock and 1,367,838 Shares. As of the date hereof, the Beneficial Ownership Limitation limits the aggregate conversion of the non-voting common stock by BVF2 to 0 out of the 2,076,085 Shares underlying the non-voting common stock, resulting in percentage beneficial ownership of approximately 5.5% of the outstanding Shares.

13

CUSIP No. 75082Q105

As of the date hereof, Trading Fund OS beneficially owns, subject to the Beneficial Ownership Limitation, 341,547 shares of non-voting common stock and 185,388 Shares. As of the date hereof, the Beneficial Ownership Limitation limits the aggregate conversion of the non-voting common stock by Trading Fund OS to 0 out of the 341,547 Shares underlying the non-voting common stock, resulting in percentage beneficial ownership of less than 1% of the outstanding Shares.

As of the date hereof, 4,892 shares of non-voting common stock and 238,543 Shares are held in the Partners Managed Accounts, subject to the Beneficial Ownership Limitation. As of the date hereof, the Beneficial Ownership Limitation limits the aggregate conversion of the non-voting common stock held by the Partners Managed Accounts to 0 out of the 4,892 Shares underlying the non-voting common stock, resulting in percentage beneficial ownership of less than 1% of the outstanding Shares.

BVF GP, as the general partner of BVF, may be deemed to beneficially own the 1,734,960 Shares beneficially owned by BVF, representing percentage ownership of approximately 7.0% of the Shares outstanding.

BVF2 GP, as the general partner of BVF2, may be deemed to beneficially own the 1,367,838 Shares beneficially owned by BVF2, representing percentage ownership of approximately 5.5% of the Shares outstanding.

Partners OS, as the general partner of Trading Fund OS, may be deemed to beneficially own the 185,388 Shares beneficially owned by Trading Fund OS, representing percentage ownership of less than 1% of the Shares outstanding.

BVF GPH, as the sole member of each of BVF GP and BVF2 GP, may be deemed to beneficially own the 3,102,798 Shares beneficially owned in the aggregate by BVF and BVF2, representing percentage ownership of approximately 12.5% of the Shares outstanding.

Partners, as the investment manager of BVF, BVF2, Trading Fund OS and the Partners Managed Accounts and the sole member of Partners OS, may be deemed to beneficially own the 3,526,729 Shares beneficially owned in the aggregate by BVF, BVF2 and Trading Fund OS and held in the Partners Managed Accounts, representing percentage ownership of approximately 14.2% of the Shares outstanding.

BVF Inc., as the general partner of Partners, may be deemed to beneficially own the 3,526,729 Shares beneficially owned by Partners, representing percentage ownership of approximately 14.2% of the Shares outstanding.

Mr. Lampert, as a director and officer of BVF Inc. may be deemed to beneficially own the 3,526,729 Shares beneficially owned by BVF Inc., representing percentage ownership of approximately 14.2% of the Shares outstanding.

As of the date hereof, Dr. Hrustanovic does not beneficially own any Shares.

(b)       Each of BVF, BVF2 and Trading Fund OS shares with Partners voting and dispositive power over the Shares each such entity beneficially owns. BVF shares with BVF GP voting and dispositive power over the Shares beneficially owned by BVF. BVF2 shares with BVF2 GP voting and dispositive power over the Shares beneficially owned by BVF2. Each of BVF GP and BVF2 GP shares with BVF GPH voting and dispositive power over the Shares each such entity beneficially owns. Trading Fund OS shares with Partners OS voting and dispositive power over the Shares beneficially owned by Trading Fund OS. Partners, BVF Inc. and Mr. Lampert share voting and dispositive power over the 3,526,729 Shares they may be deemed to beneficially own with BVF, BVF GP, BVF2, BVF2 GP, Trading Fund OS, Partners OS and BVF GPH and held in the Partners Managed Accounts.

14

CUSIP No. 75082Q105

(c)       Schedule A annexed hereto lists all transactions in securities of the Issuer by the Reporting Persons during the past sixty days. All of such transactions were effected in connection with the Issuer’s public offering (the “Offering”).

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

Item 6 is hereby amended to add the following:

On November 3, 2022, certain of the Reporting Persons and Dr. Hrustanovic entered into certain lock-up agreements (the “Lock-Up Agreements”) in connection with the Offering. Pursuant to the Lock-Up Agreements, these Reporting Persons and Dr. Hrustanovic have agreed not to, subject to certain exceptions, until the earlier of (i) December 31, 2022 or (ii) the Issuer’s public announcement of topline data from its Phase 3 MANTRA trial (the “Lock-Up Period”), without the prior written consent of Guggenheim Securities, LLC (“Guggenheim”), directly or indirectly, sell, offer, contract or grant any option to sell (including without limitation any short sale), grant any option, right or warrant to purchase, pledge, transfer, establish an open “put equivalent position” within the meaning of Rule 16a-1(h) under the Exchange Act, lend or otherwise dispose of Shares, options, rights or warrants to acquire Shares, or securities exchangeable or exercisable for or convertible into Shares currently or hereafter owned either of record or beneficially (as defined in Rule 13d-3 under the Exchange Act) by them, including, without limitation, entering into any swap or other arrangement that transfers, in whole or in part, the economic consequences of the ownership of Shares or publicly announce an intention to do any of the foregoing. These restrictions terminate after the close of trading of the Shares on the expiration of the Lock-Up Period. Guggenheim may, in its sole discretion and at any time or from time to time before the expiration of the Lock-Up Period release all or any portion of the securities subject to the Lock-Up Agreements. The foregoing description of the Lock-Up Agreements is qualified in its entirety by reference to the full text of the Lock-Up Agreements, a form of which is attached hereto as Exhibit 99.1 and incorporated herein by reference.

Stock options referencing 20,000 Shares were awarded to Dr. Hrustanovic on June 1, 2022 for no consideration in connection with his service on the Issuer’s board of directors (the “Board”). Pursuant to a certain agreement entered into between Partners and Mr. Hrustanovic, Mr. Hrustanovic is obligated to transfer the economic benefit, if any, received upon the sale of the Shares issuable upon exercise of the above referenced stock options to Partners. Such stock options shall vest in full on June 1, 2023, subject to Dr. Hrustanovic’s continued service on the Board.

Item 7. Material to be Filed as Exhibits.

Item 7 is hereby amended to add the following Exhibit:

99.1 Form of Lock-Up Agreement, dated November 3, 2022

15

CUSIP No. 75082Q105

SIGNATURES

After reasonable inquiry and to the best of his or its knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: November 10, 2022

BIOTECHNOLOGY VALUE FUND, L.P.		BIOTECHNOLOGY VALUE TRADING FUND OS LP
By:	BVF I GP LLC., its general partner	By:	BVF Partners L.P., its investment manager
		By:	BVF Inc., its general partner
By:	/s/ Mark N. Lampert
	Mark N. Lampert	By:	/s/ Mark N. Lampert
	Chief Executive Officer		Mark N. Lampert
			President
BVF I GP LLC
		BVF GP HOLDINGS LLC
By:	/s/ Mark N. Lampert
	Mark N. Lampert	By:	/s/ Mark N. Lampert
	Chief Executive Officer		Mark N. Lampert
			Chief Executive Officer
BIOTECHNOLOGY VALUE FUND II, L.P.
		BVF PARTNERS L.P.
By:	BVF II GP LLC, its general partner
		By:	BVF Inc., its general partner
By:	/s/ Mark N. Lampert
	Mark N. Lampert	By:	/s/ Mark N. Lampert
	Chief Executive Officer		Mark N. Lampert
			President
BVF II GP LLC
		BVF INC.
By:	/s/ Mark N. Lampert
	Mark N. Lampert	By:	/s/ Mark N. Lampert
	Chief Executive Officer		Mark N. Lampert
			President
BVF PARTNERS OS LTD.
		/s/ Mark N. Lampert
By:	BVF Partners L.P., its sole member	MARK N. LAMPERT
By:	BVF Inc., its general partner
By:	/s/ Mark N. Lampert	/s/ Gorjan Hrustanovic
	Mark N. Lampert	GORJAN HRUSTANOVIC
	President

16

CUSIP No. 75082Q105

SCHEDULE A

Transactions in the Securities of the Issuer During the Past Sixty Days

Class of
Security Securities
Purchased / (Sold) Price ($) Date of
Purchase / Sale

BIOTECHNOLOGY VALUE FUND, L.P.

Non-Voting Common Stock 970,171 5.8300 11/08/2022

BIOTECHNOLOGY VALUE FUND II, L.P.

Non-Voting Common Stock 685,330 5.8300 11/08/2022

BIOTECHNOLOGY VALUE TRADING FUND OS LP

Non-Voting Common Stock 54,857 5.8300 11/08/2022

BVF PARTNERS L.P.

(Through a Partners Managed Account)

Non-Voting Common Stock 4,892 5.8300 11/08/2022

EX-99.1

Exhibit 99.1

November 3, 2022

Guggenheim Securities, LLC
As Representative of the several
Underwriters referred to below

c/o Guggenheim Securities, LLC
330 Madison Avenue
New York, New York 10017

Rain Therapeutics Inc. - Lock-Up Agreement

Ladies and Gentlemen:

This letter agreement (this “Agreement”) relates to the proposed public offering (the “Offering”) by Rain Therapeutics Inc., a Delaware corporation (the “Company”), of shares of its common stock, $0.001 par value (the “Stock”), pursuant to an Underwriting Agreement (the “Underwriting Agreement”) to be entered into between the Company and Guggenheim Securities, LLC (“Guggenheim”), as representative of the several underwriters named therein (the “Underwriters”).

In order to induce you and the other Underwriters to underwrite the Offering, the undersigned hereby agrees that, without the prior written consent of Guggenheim, during the period from the date hereof until the earlier of (i) December 31, 2022 or (ii) the date of public announcement by the Company of topline data from its Phase 3 MANTRA trial (the “Lock-Up Period”), the undersigned (a) will not, directly or indirectly, offer, sell, agree to offer or sell, solicit offers to purchase, grant any call option or purchase any put option with respect to, pledge, borrow or otherwise dispose of, any Relevant Security (as defined below), and (b) will not establish or increase any “put equivalent position” or liquidate or decrease any “call equivalent position” with respect to any Relevant Security (in each case within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and the rules and regulations promulgated thereunder), or otherwise enter into any swap, derivative or other transaction or arrangement that transfers to another, in whole or in part, any economic consequence of ownership of a Relevant Security, whether or not such transaction is to be settled by delivery of Relevant Securities, other securities, cash or other consideration. As used herein “Relevant Security” means the Stock, any other equity security of the Company or any of its subsidiaries and any security convertible into, or exercisable or exchangeable for, any Stock or other such equity security.

The foregoing restrictions in this Agreement shall not apply to:

(a) the transfer of Relevant Securities (i) as a bona fide gift or gifts, (ii) by will, other testamentary document or intestate succession, (iii) to a Family Member (as defined below), (iv) to a trust for the direct or indirect benefit of the undersigned and/or one or more Family Members, (v) by operation of law, including pursuant to a domestic order, divorce settlement, divorce decree, separation agreement or pursuant to an order of a court of competent jurisdiction enforcing such agreement, (vi) to a charitable trust, (vii) to a corporation, limited liability company, partnership or other entity wholly owned by the undersigned and/or one or more Family Members, (viii) to the undersigned’s direct or indirect affiliates or to any investment fund or other entity controlled or managed by, controlling or managing, or under common control with, the undersigned (including, for the avoidance of doubt, where the undersigned is a partnership, to its general partner or a successor partnership or fund or any other funds managed by such partnership), or (ix) if the undersigned is a trust, to the beneficiary of such trust;

(b) the transfer of Relevant Securities (i) as forfeitures to satisfy tax withholding obligations of the undersigned in connection with the vesting or exercise of equity awards by the undersigned existing as of the date of the final prospectus supplement, (ii) pursuant to a net exercise or cashless exercise (to satisfy exercise price or related withholding obligations) by the undersigned of outstanding equity awards existing as of the date of the final prospectus supplement, provided that any shares of Stock acquired upon the net exercise or cashless exercise of equity awards described in this clause (b) shall be subject to the restrictions set forth in this Agreement, or (iii) transfers of the Relevant Securities to the Company by an executive officer upon death, disability or termination of employment, in each case, of such executive officer;

(c) distributions of Relevant Securities to partners, members or stockholders of the undersigned;

(d) transactions relating to Relevant Securities acquired in the Offering or in open market transactions after the closing of the Offering; and

(e) the transfer of Relevant Securities pursuant to a bona fide third-party tender offer for all outstanding shares of the Company, merger, consolidation or other similar transaction made to all holders of the Company’s securities involving a change of control of the Company (including, without limitation, the entering into of any lock-up, voting or similar agreement pursuant to which the undersigned may agree to transfer, sell, tender or otherwise dispose of Relevant Securities in connection with such transaction, or vote any Relevant Securities in favor of any transaction), provided that in the event that such tender offer, merger, consolidation or other such transaction is not completed, such securities held by the undersigned shall remain subject to the provisions of this Agreement; and

(f) transactions pursuant to any contract, instruction or plan (a “Trading Plan”) that satisfies all of the requirements of Rule 10b5-1(c)(1)(i)(B) under the Exchange Act that has been entered into by the undersigned prior to the date of this Agreement, provided, that the existence of such Trading Plan was communicated to the Representatives and such Trading Plan will not be amended or otherwise modified during the Lock-Up Period.

It shall be a further condition to any transfer or distribution pursuant to the preceding clauses (a), (b), (c), or (d) that no public disclosure or filing by any party (donor, donee, transferor or transferee) under the Exchange Act, or other public announcement shall be required or shall be made voluntarily in connection with such transfer or distribution (other than a filing on Form 5 made after the expiration of the Lock-Up Period or the filing of a required Schedule 13F or 13G, or, with respect to clauses (a), (b), (c) or (f), any filings required under Section 16 of the Exchange Act, provided that such Section 16 filings shall clearly indicate in the footnotes thereto the nature of the transfer).

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It shall be a condition to any transfer or distribution pursuant to each of the preceding clauses (a) or (c) that (x) any such transfer shall not involve a disposition for value and (y) each resulting transferee or donee of Relevant Securities executes and delivers to you an agreement satisfactory to you in which such transferee agrees to be bound by the terms of this Agreement for the remainder of the Lock-Up Period.

For purposes of this Agreement, the term “Family Member” shall mean any relationship by blood, domestic partnership, marriage or adoption not more remote than first cousin.

In addition, the restrictions described in this Agreement shall not apply to the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act, provided that no transfers occur under such plan during the Lock-Up Period and no public announcement or filing shall be required or voluntarily made by any person in connection therewith other than general disclosure in Company periodic reports to the effect that the Company directors and officers may enter into such trading plans from time to time.

Furthermore, the undersigned may, without the prior written consent of Guggenheim, (i) exercise any option to purchase shares of common stock granted under any stock incentive plan or stock purchase plan of the Company [or convert any outstanding shares of common stock into shares of non-voting common stock],¹ provided that the underlying shares of common stock shall continue to be subject to the restrictions on transfer set forth in this Agreement and (ii) transfer or surrender to the Company of shares of common stock pursuant to any contractual arrangement that provides the Company with an option to repurchase such shares of common stock in connection with the termination of the undersigned’s employment or other service relationship with the Company, provided that any filing under Section 16 of the Exchange Act shall clearly indicate in the footnotes thereto that the filing relates to the circumstances described in this clause (ii) and no other public announcement shall be required or shall be made voluntarily in connection with such transfer or surrender.

The undersigned hereby authorizes the Company during the Lock-Up Period to cause any transfer agent for the Relevant Securities to decline to transfer, and to note stop transfer restrictions on the stock register and other records relating to, Relevant Securities for which the undersigned is the record holder and, in the case of Relevant Securities for which the undersigned is the beneficial but not the record holder, agrees during the Lock-Up Period to cause the record holder to cause the relevant transfer agent to decline to transfer, and to note stop transfer restrictions on the stock register and other records relating to, such Relevant Securities. The undersigned hereby further agrees that, without the prior written consent of Guggenheim, during the Lock-Up Period the undersigned (x) will not file or participate in the filing with the U.S. Securities and Exchange Commission (the “SEC”) of any registration statement, or circulate or participate in the circulation of any preliminary or final prospectus supplement or other disclosure document with respect to any proposed offering or sale of a Relevant Security and (y) will not exercise any rights the undersigned may have to require registration with the SEC of any proposed offering or sale of a Relevant Security.

¹ This bracketed language is not included in Dr. Hrustanovic’s Lock-Up Agreement

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It is understood that, if (i) the Company notifies the Underwriters that it does not intend to proceed with the Offering, (ii) the Underwriting Agreement does not become effective, (iii) the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Stock, or (iv) the closing of the Offering pursuant to the Underwriting Agreement has not occurred by December 31, 2022, the undersigned will be released from its obligations under this Agreement.

The undersigned understands that the Company and the Underwriters will proceed with the Offering in reliance on this Agreement.

Whether or not the Offering actually occurs depends on a number of factors, including market conditions. Any Offering will only be made pursuant to the Underwriting Agreement, the terms of which are subject to negotiation between the Company and the Underwriters.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Agreement and that this Agreement constitutes the legal, valid and binding obligation of the undersigned, enforceable in accordance with its terms. Upon request, the undersigned will execute any additional documents necessary in connection with enforcement hereof. Any obligations of the undersigned shall be binding upon the successors and assigns of the undersigned from the date first above written.

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This Agreement shall be governed by and construed in accordance with the laws of the State of New York. Delivery of a signed copy of this letter by electronic or facsimile transmission shall be effective as delivery of the original hereof.

Very truly yours,
By:
	Name:
	Title:

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