Frosty reception for Ayvakit data as Blueprint pushes toward expanded label

Blueprint believes Phase II data for Ayvakit will support the kinase inhibitor’s approval as the first disease-modifying therapy for non-advanced systemic mastocytosis, but the readout dragged on the company’s stock as investors weighed whether the therapy’s commercial prospects are still as strong as previously thought.

Blueprint Medicines Corp. (NASDAQ:BPMC) announced Wednesday that Ayvakit avapritinib met the primary endpoint of mean change in total symptom score (TSS) at 24 weeks and all key secondary endpoints in Part 2 of the registrational PIONEER trial of patients with non-advanced systemic mastocytosis. Part I of the trial read out in March 2020. ...