 SOUTH SAN FRANCISCO, Calif., Aug. 13, 2021 PRNewswire -- Rigel Pharmaceuticals, Inc. Nasdaq: RIGL, today announced that the U.S. Food and Drug Administration FDA has informed the Company that clinical data submitted in late-May from a 59-patient NIHNHLBI-sponsored Phase 2 trial of fostamatinib to treat hospitalized patients suffering from COVID-19 are insufficient for an emergency use authorization EUA at this time. 