EU approves Ayvakyt for metastatic gastrointestinal stromal tumors.- Blueprint Medicines Corp

Blueprint Medicines Corp announced that the European Commission (EC) has granted conditional marketing authorization to Ayvakyt (avapritinib) as a monotherapy for the treatment of adult patients with unresectable or metastatic gastrointestinal stromal tumors (GIST) harboring the platelet-derived growth factor receptor alpha (PDGFRA) D842V mutation. For the first time in Europe, there is an approved therapy for patients with PDGFRA D842V mutant GIST specifically designed to target the underlying molecular driver of their disease.The EC approval is based on efficacy results from the Phase I NAVIGATOR trial as well as combined safety results from the NAVIGATOR and Phase III VOYAGER trials. Ayvakyt demonstrated deep and durable clinical activity and was generally well-tolerated in patients with PDGFRA D842V mutant GIST with or without prior therapy. In 38 NAVIGATOR trial patients with PDGFRA D842V mutant GIST at a starting dose of 300 mg or 400 mg once daily, Ayvakyt had an overall response rate (ORR) of 95 percent (95% CI: 82.3%, 99.4%), with 13 percent of patients achieving a complete response, and the median duration of response (DOR) was 22.1 months (95% CI: 14.1 months, not estimable). The median progression-free survival (PFS) was 24 months, and the median overall survival (OS) was not reached. These efficacy data were reported earlier this month during the European Society for Medical Oncology (ESMO) Virtual Congress 2020. The most frequently reported adverse reactions (at least 20 percent) were nausea, fatigue, anemia, periorbital edema, face edema, hyperbilirubinemia, diarrhea, vomiting, peripheral edema, increased lacrimation, decreased appetite and memory impairment.