Rigel Pharmaceuticals Inc. (NASDAQ: RIGL) shares retreated early Wednesday despite an approval from the U.S. Food and Drug Administration (FDA) for Tavalisse (fostamatinib disodium hexahydrate) for the treatment of thrombocytopenia in adult patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment.
Rigel now plans to launch its new drug in the United States in late May 2018. In patients with ITP, the immune system attacks and destroys the body’s own blood platelets, which play an active role in blood clotting and healing.
The FDA approval of Tavalisse was supported by data from the FIT clinical program. The New Drug Application (NDA) included data from 163 ITP patients and was supported by a safety database of more than 4,600 subjects across other indications in which fostamatinib has been evaluated.
James Bussel, M.D., professor emeritus of Pediatrics at Weill Cornell Medicine, was the principal study investigator on the FIT Phase 3 program. He has served as a consultant and paid member of the advisory board for Rigel, and he commented:
Chronic ITP is challenging to treat because the heterogeneity of the disease makes it difficult to predict how an individual patient will respond to available treatments and not all patients can find a treatment that works well for them. The FDA approval of fostamatinib arms physicians with a new treatment option, which works via a novel mechanism.
Shares of Rigel were last seen down about 2% at $4.02, with a consensus analyst price target of $5.78 and a 52-week trading range of $2.14 to $4.71.