Abstract
Mutations in the KRAS gene have long been implicated in the pathogenesis of colorectal cancer (CRC). KRAS G12C inhibitors overcome the "undruggable" challenge, enabling precision therapy. Garsorasib (D-1553), a highly potent and selective KRAS G12C inhibitor, has demonstrated promising anti-tumor activity and favorable safety profile in early clinical trials. We conducted an open-label, nonrandomized phase II trial (ClinicalTrials.gov, NCT04585035) to assess the safety and efficacy of garsorasib with or without cetuximab in KRAS G12C-mutated CRC. In the monotherapy cohort (n = 26), objective response rate (ORR) was 19.2% (95% CI, 6.6-39.4), disease control rate (DCR) was 92.3% (95% CI, 74.9-99.1), median progression-free survival (PFS) was 5.5 months (95% CI, 2.9-11.6) and median overall survival (OS) was 13.1 months (95% CI, 9.5-NE). In the combination cohort (n = 42), ORR was 45.2% (95% CI, 29.8-61.3), DCR was 92.9% (95% CI, 80.5-98.5), median PFS was 7.5 months (95% CI, 5.5-8.1), and median OS was not reached. Grade ≥3 treatment-related adverse events occurred in 5 (19.2%) and 6 (14.3%) patients in monotherapy and combination cohort, respectively. Garsorasib with or without cetuximab showed a promising efficacy and manageable safety profiles in heavily pretreated patients with KRAS G12C-mutated CRC, providing a potential new treatment approach for such population.