Rigel to Webcast Investor Update on October 27, 2008

SOUTH SAN FRANCISCO, Calif., Oct. 21 /PRNewswire-FirstCall/ -- Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL) today announced that it will webcast its investor update, in conjunction with the American College of Rheumatology Meeting (ACR), on October 27, 2008 from 2:00-3:00pm Pacific Time. Members of Rigel's senior management team will provide an update on the company's lead product candidate, R788, a novel, oral Syk kinase inhibitor. R788 is currently being evaluated in two Phase 2b clinical trials in patients with rheumatoid arthritis, as well as Phase 2 clinical trials in immune thrombocytopenic purpura and B-cell lymphomas.

The event will be webcast live and can be accessed from Rigel's website at www.rigel.com. Please connect to Rigel's website several minutes prior to the start of the live webcast to ensure adequate time for any software downloads that may be necessary. The webcast will be archived and available for replay on the Company's website.

In addition, Rigel will be participating in both a plenary session and a poster session during ACR in San Francisco, California from October 24-29, 2008.

    ACR Presentation Details
    Plenary session: Monday, Oct 27, 12:15-12:30 PM
    Session: Discovery 2008: Pathogenesis and Treatment of Inflammatory
    Arthritis
    Title: 1189 - Treatment of Rheumatoid Arthritis (RA) with a Syk Kinase
    Inhibitor: A 12-week randomized placebo controlled study
    Location: Hall C

    Poster session: Tuesday, Oct 28, 9:00-11:00 AM
    Session: Biology and Pathology of Bone and Cartilage
    Title: 1293 - R406, a Small Molecule Syk inhibitor, Suppresses Osteoclast
    Differentiation of Murine Bone Marrow Progenitor Cells
    Location: Hall A, Poster Board: 15

About Rigel (www.rigel.com)

Rigel is a clinical-stage drug development company that discovers and develops novel, small-molecule drugs for the treatment of inflammatory/autoimmune diseases and cancer, as well as viral and metabolic diseases. Our pioneering research focuses on intracellular signaling pathways and related targets that are critical to disease mechanisms. Rigel's productivity has resulted in strategic collaborations with large pharmaceutical partners to develop and market our product candidates. Rigel has product development programs in inflammatory/autoimmune diseases such as rheumatoid arthritis, thrombocytopenia and asthma, as well as in cancer.

     Contact: Raul Rodriguez
     Phone: 650.624.1302
     Email: invrel@rigel.com

     Media Contact: Susan C. Rogers, Alchemy Consulting, Inc.
     Phone: 650.430.3777
     Email: susan@alchemyemail.com

SOURCE Rigel Pharmaceuticals, Inc.

Released October 21, 2008