PI3Kα:RAS breaker

BridgeBio is pursuing PI3Kα:RAS breakers, which are small molecules that block RAS driven PI3Kα activation. Currently, the only approved PI3Kα inhibitor blocks all kinase activity from the protein, which interferes with normal cell signaling and ultimately, may result in hyperglycemia and insulin-driven resistance. Through its novel protein-protein interaction inhibition, breaker molecules deliver tumor selectivity that spares normal glucose metabolism as it interferes with oncogenic signaling. In addition to treating patients currently served by PI3Kα inhibitors, we expect this approach to potentially have broad utility for many other patients with oncogene-driven tumors (including HER2/HER3 dependency, RAS mutant tumors, PI3Kα mutant tumors, and tumors driven by RTK activation of RAS signaling) as both a monotherapy and in combination with other agents. The development candidate selection will take place in 2023 with IND filing in 2024.