Preclinical Characterization and Clinical Activity of RNK08954, a Highly Selective and Orally Bioavailable KRAS G12D Inhibitor

Abstract KRAS G12D is the most prevalent subtype of KRAS mutation across solid tumors, but no drug is available in the clinic. RNK08954 is a potent and selective KRAS G12D inhibitor that inhibits proliferation of KRAS G12D-mutant cells and demonstrates significant tumor regressions in mouse xenograft models while inhibiting KRAS-mediated signaling. The in vivo effects of RNK08954 are explained by its unique pharmacokinetic (PK) profile and significantly prolonged retention time in tumor tissues. RNK08954 shows synergy with immune check blockade (ICB). In a Phase 1a study, the median follow-up was 4.85 months for 36 evaluable patients. In patients with non-small cell lung cancer (NSCLC), the objective response rate (ORR, unconfirmed) is 58.33%, and in patients with pancreatic ductal adenocarcinoma (PDAC) the ORR (unconfirmed) was 33.33% in the 1000-1200mg cohort. This study supports the clinical potential of RNK08954 in patients with KRAS G12D mutation either as a single agent or in combination.