Blue­print stum­bles in PhI­II GIST tri­al, send­ing stock slid­ing, but an­a­lysts preach cau­tion

When the FDA ap­proved Blue­print’s first drug three months ago, they split their de­ci­sion. Ay­vak­it would be ap­proved for gas­troin­testi­nal stro­mal tu­mors (GIST) with a rare mu­ta­tion called PDGFRa. The oth­er half of their ap­pli­ca­tion for plain old fourth line GIST would have to wait. Reg­u­la­tors want­ed to know how the drug per­formed in a Phase III tri­al.

Re­sults are now in from that Phase III tri­al and they spelled a death-knell. In a study of 476 pa­tients with third or fourth line GIST, Ay­vak­it (avapri­tinib) per­formed worse on the pri­ma­ry end­point than the al­ready-ap­proved Bay­er GIST drug, re­go­rafenib. Pro­gres­sion-free sur­vival was 4.2 months, com­pared with 5.6 months for Ay­vak­it.

Unlock this article instantly by becoming a free subscriber.

You’ll get access to free articles each month, plus you can customize what newsletters get delivered to your inbox each week, including breaking news.

SIGN UP LOG IN BECOME A PREMIUM SUBSCRIBER