Blueprint proposes $275M follow-on after ASH gains

Blueprint Medicines Corp. (NASDAQ:BPMC) gained $16.46 (23%) to $88.32 on Monday after reporting its lead candidate, avapritinib (formerly BLU-285), led to an overall response rate (ORR) of 72% in 18 evaluable patients with advanced systemic mastocytosis (SM) in a Phase I trial. Data were presented at the American Society of Hematology meeting in Atlanta.

After market close on Monday, Blueprint proposed to raise $275 million in a follow-on underwritten by Goldman Sachs, Morgan Stanley, Cowen and Canaccord Genuity...