press release archive

Rigel Receives Milestone Payment from Daiichi in Cancer Drug Deal

SOUTH SAN FRANCISCO, CA, - January 07, 2003

Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL - News) announced that it has received the first milestone payment from Daiichi Pharmaceuticals Co., Ltd, in conjunction with the companies' partnership to develop a new type of oncology drug.

The two companies are collaborating on research related to protein degradation, an emerging strategy for treating cancer. The deal, which began last August, is one of the first industry collaborations focused on drug development in this field.

In addition to its partnership with Daiichi, Rigel has its own broader, proprietary drug development program aimed at protein degradation. This effort is directed at a novel class of drug targets called ligases. Ligases are enzymes that regulate protein degradation, which in turn helps control cell division. This property makes ligases a potentially important target for new cancer therapies. Rigel’s ligase research program has already uncovered a number of compounds that have been shown in laboratory studies to inhibit replication of tumor cells. Rigel expects to move the first of its own ligase drugs into clinical evaluation in 2004.

"It now appears that ligases and related targets could hold as much potential for drug development as kinases did a decade ago," said James Gower, Rigel’s chief executive officer. "We believe that our collaboration with Daiichi together with our internal development program puts Rigel at the forefront of commercial research into this important new class of drug target."

About Rigel
Rigel's mission is to become a source of novel, small-molecule drugs to meet large, unmet medical needs. The company's business model is to develop a portfolio of drug candidates and to take these through phase II clinical trials, after which Rigel intends to seek commercialization partners for completion of clinical evaluation, regulatory approval and marketing. Rigel has identified three areas for its lead product research programs: mast cell inhibition to treat immunologic diseases such as asthma/allergy and autoimmune disorders, antiviral agents to treat hepatitis C, and ubiquitin ligases, a new class of cancer drug target. Rigel has begun clinical testing of its first product, for allergic rhinitis, and plans to follow this with two additional drugs in the clinic by the end of 2003. Rigel's approach to drug discovery is based on advanced, proprietary functional genomics techniques that allow the company to identify targets with a demonstrable role in a disease pathway and to efficiently screen for those that are likely to be amenable to drug modulation.

This press release contains "forward-looking" statements, including statements related to Rigel's business strategy, drug development programs, collaborations and clinical trial plans. Any statements contained in this press release that are not statements of historical fact may be deemed to be forward-looking statements. Words such as "plans," "appears," "could," "intends," "expects," "believes" and similar expressions are intended to identify these forward-looking statements. There are a number of important factors that could cause Rigel's results to differ materially from those indicated by these forward-looking statements, including the risks detailed from time to time in Rigel's SEC reports, including its Annual Report on Form 10-K for the year ended December 31, 2001. Rigel does not undertake any obligation to update forward-looking statements.