press release archive

Rigel Announces Milestone Payment from Pfizer for Validated Target for Respiratory Drug Development

South San Francisco, CA - November 28, 2001

Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL) today announced that Pfizer Inc. (NYSE: PFE) has accepted a validated drug target from Rigel, which will result in a milestone payment.

"We are pleased that Pfizer has selected this target, which we believe has potential for asthma/allergy drug development," said James M. Gower, chairman and chief executive officer of Rigel, who will be speaking later today at The Robertson Stephens Medical Conference in New York. "This collaboration is successfully meeting its research objectives to identify possible targets for the development of products for the management of certain respiratory diseases."

The companies originally entered into a two-year agreement in January 1999 to use Rigel's proprietary peptide libraries to identify intracellular drug targets that control production of IgE, a key mediator in allergic reactions and asthma, in B cells. In 2001, Pfizer extended the agreement for an additional year. Under the terms of this agreement, Pfizer provides Rigel with target validation and research milestones as well as milestone and royalty payments relating to the development and commercialization of any human or animal therapeutics resulting from the collaboration. Pfizer will have worldwide rights to develop and market human and veterinary drugs for use against the targets that inhibit the switch to IgE in B cells.

Robertson Stephens Webcast Details
Mr. Gower will present at the Robertson Stephens Medical Conference today at 1:30 p.m. EST in the Wedgewood Room at the Pierre Hotel. His presentation will be available via webcast replay starting at 3:30 p.m. EST, and can be accessed by logging onto the "Investor Resources" section of Rigel's website at www.rigel.com.

Rigel Pharmaceuticals is a drug discovery and development company that uses advanced functional genomics tools to discover novel drug targets. Rigel's technology is designed to identify molecules that play an important role in regulating a human cell's response to disease by testing a very large number of proteins in a very large number of cells to determine which proteins will change the cell's response to the disease. Rigel currently has programs in asthma/allergy, autoimmunity, transplant rejection, rheumatoid arthritis, inflammatory bowel disease, chronic bronchitis, cancerous tumor growth and hepatitis C. In addition to its program with Pfizer, Rigel has multi-year collaborations with Cell Genesys, Inc., Janssen Pharmaceutica N.V. and Novartis Pharma A.G. Rigel is based in South San Francisco, California.

Statements included in this press release that are not historical in nature are "forward-looking statements" within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. These statements include those relating to the anticipated progress and success of the Pfizer collaboration. Rigel cautions readers that forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those indicated in the forward-looking statements due to the risks and factors identified in Rigel's Annual Report on Form 10-K for the year ended December 31, 2000 and other filings made with the Securities and Exchange Commission from time to time. The information in this press release is current as of its release date. Rigel does not intend to update the forward-looking information contained in this press release.