Rigel Pharmaceuticals, Inc. is a clinical-stage drug development company. The Company discovers and develops small-molecule drugs for the treatment of inflammatory and autoimmune diseases, immuno-oncology related diseases, and muscle disorders. Its research focuses on intracellular signaling pathways and related targets that are critical to disease mechanisms. It has various product candidates in development: fostamatinib; R348; two oncology product candidates, and two preclinical programs. Fostamatinib is an oral spleen tyrosine kinase (SYK) inhibitor. R348 is a topical janus kinase (JAK)/SYK inhibitor. It is conducting research in the disease areas of inflammation/immunology and muscle wasting/muscle endurance.