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Filed Pursuant to
Rule 424(b)(3) and (c)
File No. 333-106942

Prospectus Supplement No. 7
Dated August 20, 2004
To Prospectus Dated July 23, 2003

Rigel Pharmaceuticals, Inc.
9,583,331 Shares
Common Stock

        This prospectus supplement supplements the prospectus, dated July 23, 2003, of Rigel Pharmaceuticals, Inc. relating to the offering and sale by selling stockholders of Rigel (or by donees, pledgees, transferees and other successors in interest that receive such shares as a gift, pledge, partnership distribution or other non-sale transfer) of 9,583,331 shares of our common stock. This prospectus supplement should be read in conjunction with the prospectus, and is qualified by reference to the prospectus, except to the extent that the information presented herein supercedes the information contained in the prospectus. The term "Selling Stockholders" as used in the prospectus shall be deemed to include the selling stockholders identified in the table below. This prospectus supplement is not complete without, and may not be delivered or utilized except in connection with, the prospectus, including any amendments or supplements thereto.

        Investing in our securities involves a high degree of risk. See "Risk Factors" beginning on page 1 of the prospectus.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

        This prospectus supplement is being filed in connection with the distribution of shares held by Alta California Partners, L.P., Alta Embarcadero Partners, LLC, Alta BioPharma Partners II, L.P. and Alta Embarcadero BioPharma Partners II, LLC (collectively, the "Alta Funds"), each identified in the prospectus as a selling stockholder, to their partners and members. No additional shares of Rigel common stock are being offered for resale hereunder. Except with respect to directors and officers of Rigel, the Alta Funds and entities that have filed reports pursuant to Section 13(f) of the Securities Exchange Act of 1934, as amended (the "Act"), and statements of beneficial ownership filed pursuant to Sections 13(d) and 13(g) of the Act, the ownership indicated in the table below is based solely on shares owned by the indicated selling stockholders as a result of distributions of shares by the Alta Funds. The table appearing on pages 16 and 17 of the prospectus under the caption "Selling

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Stockholders" is supplemented and amended to include the following stockholders in addition to those identified in the prospectus:

		Ownership Before Offering						Ownership After Offering
Name and Address of Owner***						Shares Offered
		Shares		Percent*				Shares		Percent*
Alta California Partners, L.P.(1) One Embarcadero Center, Suite 4050 San Francisco, CA 94111		33,947		**		33,947		0		**
Alta Embarcadero Partners, LLC(1) One Embarcadero Center, Suite 4050 San Francisco, CA 94111		776		**		776		0		**
Alta BioPharma Partners II, L.P.(1) One Embarcadero Center, Suite 4050 San Francisco, CA 94111		1,025,470		5.6	%	1,025,470		0		**
Alta Embarcadero BioPharma Partners II, LLC(1) One Embarcadero Center, Suite 4050 San Francisco, CA 94111		37,723		**		37,723		0		**
1999 Farah Hyder Champsi Trust		1,998		**		1,388		610		**
Anne Davis Living Trust Dtd 1/22/04		7,359		**		1,871		5,488		**
A. Rachel Leheny		380		**		264		116		**
Alison de Bord		492		**		342		150		**
Andreas Bremer		286		**		198		88		**
Arnold T Hagler Separate Property Trust dtd 9/17/97		142		**		99		43		**
Arun K. Aggarwal		47		**		33		14		**
ASF Montparnasse Limited		10,938		**		2,782		8,156		**
B.A. Ventures, Inc.		572		**		278		294		**
Bank of America Capital Corporation		14,250		**		9,902		4,348		**
Bear Stearns Securities (Custodians) for Douglas I. Lovison		219		**		56		163		**
Blackboard Ventures, Inc.		38,000		**		26,405		11,595		**
Boatmen's Trust F/B/O Laura Hoblitzelle		437		**		111		326		**
Brian E. Cobb		510		**		234		276		**
Brian W. McNeill		296		**		117		179		**
BSD & T of CA As Agent For 1051-0032-006		437		**		111		326		**
BSD & T of CA As Trustee For 1051-0005-002		437		**		111		326		**
Burr Family Investment Company, LLC		3,680		**		936		2,744		**
California Public Employees' Retirement System		397,785	(2)	1.9	%	141,433		256,352	(2)	1.4	%
Chase Capital Partners Private Equity Fund of Funds		19,000		**		13,202		5,798		**
Christopher Walsh		95		**		66		29		**
CINQ-M Participations		475		**		330		145		**

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Claudio Engel		380		**		264		116		**
Comerica Capital Advisors		950		**		660		290		**
Continental Investments Corporation, LLC		2,044		**		938		1,106		**
Craig L. Burr 1985 Children's Trust		1,146		**		501		645		**
Craig L. Burr Revocable Trust		671		**		171		500		**
Daniel Fred Goodman		190		**		132		58		**
Daniel H. Case Separate Property Non-Exempt Marital Trust		475		**		330		145		**
Daniel Janney and Noelle Montgomery Family Trust		4,084		**		1,217		2,867		**
Daniel Richner		190		**		132		58		**
Daniel V. Santi		95		**		66		29		**
David E. Retick Trust		27		**		7		20		**
Deleage Children's Trust FBO Andre Deleage		2,329		**		660		1,669		**
Deleage Children's Trust FBO Emmanuel Deleage		2,329		**		660		1,669		**
Deleage Children's Trust FBO Michel Deleage		2,329		**		660		1,669		**
Deleage Children's Trust FBO Phillippe Deleage		2,329		**		660		1,669		**
Des femmes Foundation, Inc.		475		**		330		145		**
Dolly Champsi		475		**		330		145		**
Edward E. Penhoet		3,181		**		2,210		971		**
Edward Hurwitz		76		**		53		23		**
Eileen McCarthy		1,947		**		513		1,434		**
Elliot B. & Pascale V. Evers Revocable Trust		832		**		337		495		**
Eric W. Roberts		475		**		330		145		**
Eugene G. Chen		47		**		33		14		**
Eurazeo		28,500		**		19,804		8,696		**
Finedix, B.V.		4,750		**		3,301		1,449		**
Fleet National Bank & Edith N.K. Meyer Trustees U/I C.P. Knight, Jr. Residuary Trust DTD 12/19/61 as Amended		547		**		139		408		**
Francois A. L'Eplattenier		190		**		132		58		**
Fred S. Endsley, as Trustee of General Fund c/u/a Dtd August 10, 1987		437		**		111		326		**
Garden Bay Investors		190		**		132		58		**
Garrett P. Gruener		15,865		**		4,421		11,444		**
GC&H Investments		1,306		**		499		807		**
Geoffrey R. Hoguet		201		**		51		150		**

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Guy Paul Nohra and Linda Nohra, Nohra Living Trust		11,442		**		3,087		8,355		**
H. Michael Cohen		95		**		66		29		**
Hans Tjian		95		**		66		29		**
Harris Barton		475		**		330		145		**
Health Partners Holdings Limited		1,900		**		1,320		580		**
Hilary Strain		202		**		140		62		**
Hoblitzelle FBO Christopher Augur		146		**		37		109		**
Hoblitzelle FBO Harrison H. Augur		145		**		37		108		**
Hoblitzelle FBO Newell A. Augur Jr.		146		**		37		109		**
Howard Hughes Medical Institute		28,500		**		19,804		8,696		**
James Cervantes		95		**		66		29		**
James M. Gower(3)		125,628		**		264		125,364		**
Jean Deleage(4)		9,593		**		2,832		6,761		**
Jean-Philippe Tripe		190		**		132		58		**
John Clawson		95		**		66		29		**
JP Morgan Chase Bank as Trustee of the Corning Inc. Retirement Master Trust		9,500		**		6,601		2,899		**
Kenneth E. Williams		95		**		66		29		**
Khaled Nasr		101		**		70		31		**
Kingsley Profit Sharing Trust		67		**		17		50		**
KJM Florida Trust		475		**		330		145		**
Le Serre		173		**		76		97		**
Len R. Small		285		**		198		87		**
Lip-Bu Tan & Ysa Loo, TTES FBO Lip-Bu Tan & Ysa Loo Trust UTD 2/3/92		285		**		198		87		**
Lockard/Marduel Revocable Trust		1,903		**		1,322		581		**
Lotus BioScience Investment Holdings Ltd		19,000		**		13,202		5,798		**
Lushtak Family Living Trust DTD 8/9/99		475		**		330		145		**
Mahendra G. Shah		95		**		66		29		**
Marc L. Abramowitz		475		**		330		145		**
Marina Bozilenko		475		**		330		145		**
Mario M. Rosati, Trustee of the Mario M. Rosati Trust U/D/T 1/5/90		142		**		99		43		**
Mark J. and Becky R. Levin		475		**		330		145		**
Mellon Bank As Agent For 1026-032245-8		547		**		139		408		**
Mellon Bank As Agent For 1026-032279-7		547		**		139		408		**

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Mellon Bank As Agent For 1083-671500-0		437		**		111		326		**
Mellon Bank As Agent For 1083-67D200-7		437		**		111		326		**
Mellon Bank As Agent For 1083-67I600-0		874		**		222		652		**
Mellon Bank As Agent For 1084-28YW01-6		219		**		56		163		**
Mellon Bank As Agent For 1084-316H01-4		547		**		139		408		**
Mellon Bank As Agent For 1084-33VX00-0		437		**		111		326		**
Mellon Bank As Trustee For 1026-018408-0		1,094		**		278		816		**
Mellon Bank As Trustee For 1026-019556-5		1,094		**		278		816		**
Mellon Bank As Trustee For 1026-460574-2		437		**		111		326		**
Mellon Bank As Trustee For 1026-460581-7		437		**		111		326		**
Mellon Bank As Trustee For 1026-540503-5		656		**		167		489		**
Mellon Bank As Trustee For 1084-09FN42-1		2,187		**		556		1,631		**
Mellon Bank As Trustee For 1084-09FN46-0		547		**		139		408		**
Mellon Bank As Trustee For 1051-067700-0		437		**		111		326		**
Mellon Bank NA As Agent For Account 1026-020287-0		2,187		**		556		1,631		**
Mellon Bank NA As Agent For Account 1026-402383-0		2,187		**		556		1,631		**
Mellon Bank NA As Agent For Account 1026-047161-0		19,000		**		13,202		5,798		**
Mellon Bank NA As Custodian For Account 1026-071459-0		437		**		111		326		**
Michael G. Dovey Individual Account		95		**		66		29		**
Mitchell H. Gage		190		**		132		58		**
Mumtaz H. Champsi		380		**		264		116		**
Needham & Company, Inc.		1,094		**		278		816		**
Niel H. Sherman		76		**		53		23		**
North Star Venture Mgmt Inc. Pst F/B/O Terrance Mcguire		134		**		34		100		**
Northern Trust Bank of Florida A/C F22316700, Fred Endsley Insurance Trust dtd 6/27/78, Fred Endsley Trustee		437		**		111		326		**
Nottingham Trust		107		**		27		80		**
Old Westbury Venture Capital Fund, L.L.C.		26,195		**		6,661		19,534		**
Peter S. Handy		656		**		167		489		**
Peter Seeburg		3,800		**		2,641		1,159		**
PH Investments, LLC		547		**		139		408		**
PharmaBio Development		9,500		**		6,601		2,899		**

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R. Scott Greer		950		**		660		290		**
Raijacur, N.V.		5,700		**		3,961		1,739		**
Rainicur, N.V.		5,700		**		3,961		1,739		**
Revocable Trust of Gerald M. Rubin		475		**		330		145		**
Robert Simon		101		**		70		31		**
RockPoint Capital II		9,500		**		6,601		2,899		**
Sanford Robertson & Jeanne Robertson, Trustees of the Robertson Revocable Trust dated 11/27/02		475		**		330		145		**
Scaler Foundation		1,425		**		990		435		**
Scott C. Sollers		152		**		106		46		**
Silicon Valley Bancshares		547		**		139		408		**
Soparexo		5,700		**		3,961		1,739		**
Stephanie Lovison Trust dtd 10/3/01, Stephanie Lovison Trustee		219		**		56		163		**
Sutro Investment Partners VI, LLC		950		**		660		290		**
Swan Ventures, L.P.		1,900		**		1,320		580		**
Taha Tippu Hyder Champsi		190		**		132		58		**
Tandon Family Trust		2,187		**		556		1,631		**
Teachers Insurance and Annuity Association of America		38,000		**		26,405		11,595		**
The Clarence Westbury Foundation		570		**		396		174		**
The McGuire Family Irrevocable Trust		190		**		132		58		**
The Nohra 1996 Credit Trust U/A/D 12/2/96		3,680		**		936		2,744		**
The Sutro Group		1,094		**		278		816		**
Theodore A. Bosler Trust U/A 4/21/93		328		**		83		245		**
Thomas B. King		190		**		132		58		**
Thomas J. Dietz		190		**		132		58		**
Thuban Partners L.P.		142		**		99		43		**
Timothy L. Dibble		80		**		20		60		**
Timothy P. Neher		547		**		139		408		**
Virginia M. Turezyn		190		**		132		58		**
Waldemar Jantz		475		**		330		145		**
Warren E. Miller and Britt Marie E. Ljung Living Trust dtd 6/20		95		**		66		29		**
Wells Fargo Bank Minnesota NA & Frank Polestra Co-Executors for Marino Polestra Estate		7,417		**		1,897		5,520		**

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William J. Steding		219		**		56		163		**
William P. Egan		671		**		171		500		**
William P. Egan 1985 Childrens Trust F/B/O Gregory J. Egan		287		**		126		161		**
William P. Egan 1985 Childrens Trust F/B/O Kristen E. Reed		287		**		126		161		**
William P. Egan 1985 Childrens Trust F/B/O Mark P. Egan		287		**		126		161		**
William P. Egan 1985 Childrens Trust F/B/O William P. Egan III		287		**		126		161		**
William Thomas Lockard, Trustee and Alix Marduel, Trustee—Lockard/Marduel Revocable Trust		475		**		330		145		**
WS Investment Company 96A		201		**		51		150		**
WS Investment Company, LLC (2000)		142		**		99		43		**
WS Investment Company, LLC (2000B)		190		**		132		58		**
Total		1,877,149		10.5	%	1,480,549		396,600		2.5	%

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*

Percentage calculations based on 18,454,166 shares of our common stock that were issued and outstanding as of August 17, 2004.

**

Less than 1%

***

Addresses that are not listed are c/o Alta Partners, One Embarcadero Center, Suite 4050, San Francisco, CA 94111.

(1)

Includes 33,947 shares of common stock that are subject to purchase by Alta California Partners, L.P., 776 shares of common stock that are subject to purchase by Alta Embarcadero Partners, LLC, 217,686 shares of common stock that are subject to purchase by Alta BioPharma Partners II, L.P. and 8,008 shares of common stock that are subject to purchase by Alta Embarcadero BioPharma Partners II, LLC under warrants that are currently exercisable. Jean Deleage, PhD, a director of Rigel since 1997, is a principal of Alta Partners and a general partner, managing director, manager or member of the foregoing funds. As a general partner, managing director, manager or member of the foregoing funds, Dr. Deleage may be deemed to share voting and investment powers for the shares held by the foregoing funds. Dr. Deleage disclaims beneficial ownership of the shares held by funds affiliated with Alta Partners except to the extent of his proportionate pecuniary interest therein.

(2)

Includes 55,545 shares of common stock as disclosed on a Form 13F for the quarter ended June 30, 2004.

(3)

Includes 125,248 shares of common stock previously owned by Mr. Gower. Mr. Gower is the Chairman of the Board and Chief Executive Officer of Rigel.

(4)

Dr. Deleage is a director of Rigel.

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Filed Pursuant to Rule 424(b)(3) and (c) File No. 333-106942

Prospectus Supplement No. 7 Dated August 20, 2004 To Prospectus Dated July 23, 2003