BridgeBio Oncology Therapeutics has unveiled promising preclinical data for BBO-11818, a novel panKRAS inhibitor designed to address the significant unmet medical need in KRAS-driven cancers. The data, presented at the 2025 AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, demonstrate the compound's potential to target a broader range of KRAS mutations than currently available therapies.
Addressing KRAS Mutation Diversity
KRAS represents one of the most commonly mutated oncogenes in human cancers, yet current therapeutic options remain limited. As Pedro Beltran, PhD, Chief Scientific Officer of BridgeBio Oncology, explained, "While current KRASG12C inhibitors have shown promising clinical efficacy, they only address a subset of mutations, leaving many patients without effective options."
BBO-11818 was specifically designed as a potent panKRAS inhibitor with strong binding affinity for KRAS and broad selectivity over HRAS and NRAS. The compound targets KRAS in both the ON (active GTP-bound) and OFF (inactive GDP-bound) states, representing a comprehensive approach to KRAS inhibition.
Robust Preclinical Efficacy Data
The preclinical studies revealed impressive potency metrics for BBO-11818. Cell-based assays confirmed that the compound potently inhibits ERK phosphorylation and proliferation in KRAS mutant cell lines, achieving single-digit nanomolar EC50 values. The selectivity profile proved equally compelling, with BBO-11818 demonstrating over 1000-fold lower potency against NRAS, HRAS, and BRAF-mutant cell lines compared to KRAS mutant cells.
In monotherapy studies, BBO-11818 showed strong anti-tumor responses with favorable pharmacokinetics and oral bioavailability. The compound demonstrated dose- and time-dependent inhibition of pERK in in vivo pharmacodynamic studies and achieved tumor regressions at well-tolerated doses in cell-derived xenograft models of KRAS mutant pancreatic, non-small cell lung, and colorectal cancer.
Combination Therapy Potential
The preclinical program also explored combination approaches with encouraging results. Treatment combining BBO-11818 with BBO-10203, the company's selective RAS:PI3Kα breaker that blocks RAS-mediated activation of the PI3K-AKT pathway, demonstrated enhanced anti-tumor activity both in vitro and in xenograft models. The efficacy of this combination was driven by a robust decrease in tumor cell proliferation and increase in apoptosis.
Additional combination studies showed promise with established therapies. BBO-11818 combined with cetuximab, an approved anti-EGFR monoclonal antibody, demonstrated enhanced anti-tumor activity. Perhaps most notably, combination with anti-PD-1 treatment resulted in complete tumor regressions in the KRASG12D CT26 syngeneic tumor mouse model.
Clinical Development Timeline
BBO-11818 is currently being evaluated in the Phase 1 KONQUER-101 trial, which is enrolling patients with KRAS mutant pancreatic, non-small cell lung, and colorectal cancer harboring KRASG12A, KRASG12C, KRASG12D, KRASG12S, or KRASG12V mutations, or KRAS amplification. Initial Phase 1 clinical data are expected in the second half of 2026.
"We are pleased to share this updated preclinical data on BBO-11818, which further reinforces its clinical potential," said Eli Wallace, PhD, Chief Executive Officer of BridgeBio Oncology. "These results support further evaluation of BBO-11818 as a monotherapy and in combination as we continue to drive efforts to deliver meaningful value to patients and work towards fully unlocking the potential of RAS-focused therapies by optimizing target coverage."
The comprehensive preclinical dataset positions BBO-11818 as a potentially differentiated approach to targeting KRAS-driven malignancies, with the breadth of mutation coverage and combination potential offering hope for patients currently lacking effective treatment options.
