Data are to come next week on Mirati’s adagrasib, and if the group is to maintain its monster valuation of nearly $9bn it cannot afford to disclose any diminution of the Kras G12C-selective inhibitor’s effects. Adagrasib, formerly known as MRTX849, will be the subject of two presentations at the Triple (EORTC-NCI-AACR) meeting. LBA-03, revealing updates in NSCLC, is a plenary; LBA-04 covers colorectal cancer and other solid tumours. So far adagrasib seems to have the edge over its main competitor, Amgen’s sotorasib, but with far lower patient numbers. And response rates with sotorasib in NSCLC dwindled on central review, from around 54% a year ago to 35% last month, something Mirati will be keen to avoid. Amgen plans to file on its phase II data, but Mirati has not yet made its filing intentions plain; the group is planning an investor event after the presentations on October 25 at which it might address this issue. Mirati will also use its investor meeting to reveal plans for MRTX1133, another Kras inhibitor but this time selective for G12D, a mutation Mirati says is relevant in a greater number of patients than G12C.
|Cross-trial comparison of Amgen and Mirati data so far|
|Target dose||600mg twice daily||960mg once daily|
|NSCLC||3/5 PRs (60% ORR)||12/34 PRs (35% ORR)|
|Colorectal cancer||1/2 PRs (50% ORR)||3/25 PRs (12% ORR)|
|Source: NEJM, Esmo & company announcements. PR=partial remission; ORR=overall response rate.|