KRAS & RAS inhibitors

Patients with KRAS G12C lung cancer that has progressed after chemo-immunotherapy can take an oral KRAS inhibitor instead of docetaxel and gain a somewhat longer time to progression with fewer severe side effects, but should understand that most tumours become resistant within a year and that survival is not improved. KRAS G12C testing is worthwhile, but first-generation inhibitors are a step rather than a cure; combinations and next-generation inhibitors are the active research fronts.

Patients with metastatic colorectal cancer carrying a KRAS G12C mutation (about 3-4% of cases) who have exhausted standard chemotherapy now have a targeted option that works far better than trifluridine-tipiracil or regorafenib. The higher sotorasib dose is clearly superior, and the EGFR antibody is essential because KRAS inhibition alone barely works in bowel cancer. Responses are still modest and short-lived compared with EGFR or ALK inhibitors in lung cancer.

The most frequently mutated oncogene in cancer stopped being undruggable, and patients with KRAS G12C lung and bowel cancers now have targeted pills. The approach, exploiting a mutation-created chemical handle and an inactive-state pocket, has become a template for other hard targets.