Rigel gets first FDA approval with Tavalisse

FDA approved an NDA from Rigel Pharmaceuticals Inc. (NASDAQ:RIGL) for Tavalisse fostamatinib to treat chronic idiopathic thrombocytopenic purpura in adults who have had an insufficient response to a previous treatment. The oral spleen tyrosine kinase (SYK) inhibitor is the company's first product to be approved by any regulatory agency since its founding in 1996.

Rigel expects to launch Tavalisse late next month. A Rigel spokesperson declined to disclose the drug's wholesale acquisition cost (WAC)...