Rigel Pharmaceuticals, Inc. is a biotechnology company dedicated to discovering, developing and providing novel, small molecule drugs that significantly improve the lives of patients with immune and hematological disorders, cancer and rare diseases. Rigel's pioneering research focuses on signaling pathways that are critical to disease mechanisms. Its clinical programs include clinical trials of fostamatinib, an oral spleen tyrosine kinase (SYK) inhibitor, in a number of indications. The Company has submitted an NDA to the FDA for fostamatinib in patients with chronic or persistent ITP. The investigation of fostamatinib also includes Phase 2 clinical trials for autoimmune hemolytic anemia and IgA nephropathy.