Rigel Pharmaceuticals, Inc., a biotechnology company, engages in discovering, developing, and providing small molecule drugs that enhance the lives of patients with hematologic disorders, cancer, and rare immune diseases. The company's commercialized products include Tavalisse, an oral spleen tyrosine kinase inhibitor for the treatment of adult patients with chronic immune thrombocytopenia; and Rezlidhia, a non-intensive monotherapy for the treatment of adult patients with relapsed or refractory (R/R) acute myeloid leukemia (AML) with a susceptible isocitrate dehydrogenase-1 (IDH1) mutation as detected by an FDA-approved test. It also develops Fostamatinib that has conducted phase III clinical trials for the treatment of warm autoimmune hemolytic anemia; has completed FOCUS phase III clinical trial for the treatment of hospitalized high-risk patients COVID-19; and that is in phase III clinical trials for the treatment of COVID-19 in hospitalized patients. In addition, its other clinical programs include interleukin receptor-associated kinase inhibitor program and a receptor-interacting serine/threonine-protein kinase inhibitor program in clinical development with partner Eli Lilly and Company. Further, the company has product candidates in clinical development with partners BerGenBio ASA and Daiichi Sankyo. Rigel Pharmaceuticals, Inc. was incorporated in 1996 and is headquartered in South San Francisco, California.