Mirati seeks to shrug off sitravatinib flop

Mirati’s broadly acting tyrosine kinase inhibitor sitravatinib always looked like a long shot, so perhaps the most surprising thing about yesterday’s Sapphire trial failure is that it caught investors unawares: the group’s stock fell 13% this morning. The project looks dead despite an ongoing study in treatment-naive patients and Beigene-backed trials of tislelizumab combos. Much more important to Mirati, though, is the launch of Krazati in second-line NSCLC, expanding that product’s use into earlier lines and new indications, and the group’s remaining pipeline. This month, Krazati’s first full quarter of sales beat expectations, but there are already signs of a broad Kras flatlining. Expanding into the potentially lucrative first-line NSCLC market is therefore key for Mirati, but Keytruda-combo data here looked lacklustre; SVB analysts suggested that the addition of chemotherapy, being tested in Krystal-17, might help. Mirati has yet to nail down its strategy in first-line lung, and investors will hope that things move more quickly than in colorectal cancer, where a filing is now due by year-end. As for the pipeline, data on a PRMT5 inhibitor are up next, although this mechanism has disappointed in the past.