Blueprint reports additional Phase I data for BLU-285 in GIST

In an abstract released ahead of the American Society of Clinical Oncology meeting in Chicago, Blueprint Medicines Corp. (NASDAQ:BPMC) reported additional data from an open-label, international Phase I trial evaluating once-daily 30-600 mg oral BLU-285 to treat unresectable gastrointestinal tumors (GIST) and other relapsed or refractory solid tumors. In 17 evaluable patients with platelet derived growth factor receptor A (PDGFRA; PDGFR2; CD140A)-driven GIST, BLU-285 led to an overall response rate (ORR) of 41%, including 7 confirmed partial responses, plus 10 cases of stable disease. In 11 evaluable patients with stem cell factor (SCF) receptor tyrosine kinase (c-Kit; KIT; CD117)-driven GIST, BLU-285 led to an ORR of 18%, including 2 partial responses, plus 5 cases of stable disease.

The trial is evaluating primary endpoints of maximum tolerated dose (MTD) and recommended Phase II dose (Part 1), safety (Parts 1 and 2) and ORR (ORR) (Part 2). Secondary endpoints include pharmacokinetics, duration of response, progression-free survival (PFS) and clinical benefit rate (CBR)...