Bristol stops SOS1
Bristol Myers Squibb has discontinued its SOS1 inhibitor, the company revealed in its third-quarter earnings presentation last week. The asset, BMS-986509, came via the $4.8bn purchase of Mirati, although that deal was driven by the G12C inhibitor Krazati. Bristol didn’t give details about BMS-986509’s demise, although presumably a phase 1/2 solid tumour trial, studying the project with or without Krazati, returned disappointing results. The move comes after Boehringer canned its pan-KRAS:SOS1 inhibitor BI 1701963 last year, although 2024 also saw Bayer start a phase 1 study of its SOS1 inhibitor BAY 3498264, with or without Amgen’s Lumakras. The only other SOS1 assets in clinical development, according to OncologyPipeline, are in China: namely, Suzhou Zelgen’s ZG2001 and Sichuan Huiyu’s HYP-6589. Plenty of preclinical work is ongoing, although this arena has also seen discontinuations, such as that of Erasca’s ERAS-9. Bristol discontinued another Mirati-originated project, the KRAS G12D inhibitor MRTX1133, earlier this year; although the PRMT5 inhibitor BMS-986504, also gained through the deal, recently began the phase 2/3 Mountain-TAP29 trial in first-line NSCLC. Still, there have always been questions about Mirati’s price tag, especially with Krazati selling just $149m in the first nine months of this year.
Clinical-stage SOS1 inhibitors
| Project | Description | Company | Key trial | Note |
|---|---|---|---|---|
| ZG2001 | Pan-KRAS:SOS1 inhibitor | Suzhou Zelgen Biopharmaceuticals | China ph1/2 in solid tumours | Completes Feb 2026 |
| HYP-6589 | SOS1 inhibitor | Sichuan Huiyu Pharmaceutical | China ph1/2 in solid tumours | Completes Jul 2026 |
| BAY 3498264 | SOS1 inhibitor | Bayer | Global (OUS) ph1 in solid tumours, +/- Lumakras | Completes Jul 2027 |
Source: OncologyPipeline.
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