Rigel Pharmaceuticals' Fostamatinib Flunks In Late-Stage Rare Blood Disorder Trial

Rigel Pharmaceuticals Inc RIGL shares are falling on disappointing data from the FORWARD Phase 3 trial of fostamatinib in patients with warm autoimmune hemolytic anemia (wAIHA).
wAIHA is an autoimmune disorder characterized by the premature destruction of healthy red blood cells (hemolysis).
The trial did not demonstrate statistical significance in the primary efficacy endpoint of durable hemoglobin response in the overall study population.
Related: Knight Therapeutics Secures Rights To Rigel's Fostamatinib In Latin America.
In a post-hoc regional analysis of U.S., Canadian, Australian, and Western European trial sites, patients treated with fostamatinib had a more durable hemoglobin response than placebo, whereas not for the patients in the Eastern European trial sites.
Rigel plans to continue analyzing the data to understand the geographical differences in patient disease characteristics and outcomes and discuss these findings with the FDA.
Also Read: Rigel Stock Falls After Update From COVID-19 Program.
The safety and tolerability profile in the FORWARD trial was consistent with the existing fostamatinib safety database.
Price Action: RIGL shares are down 49.1% at $0.90 during the market session on the last check Wednesday.