RMC-6236 is a non-covalent pan-RAS(ON) inhibitor from Revolution Medicines, which shows remarkable efficacy in tumors driven by RAS mutants that were previously considered “undruggable,” such as G12V/D/A/S, G13X, and Q61X. RMC-6236 exerts its action via a “tri-complex” mechanism, gluing RAS to the ubiquitously expressed chaperone protein, cyclophilin A. Our in-depth article covers the presentation given at the AACR 2024 meeting, which outlines the discovery and preclinical profile of RMC-6236 as well as the latest clinical updates.

STX-478 is a wild-type-sparing, oral, CNS-penetrant, novel allosteric inhibitor of mutant PI3Kα (phosphatidylinositol-3 kinase α) targeting a cryptic pocket near the ATP-binding site. PI3Kα plays a central role in many cancers, and has been recently highlighted in coverage of 2021 Molecule of the Year nominee and PI3Kα degrader inavolisib. Currently approved PI3Kα modulators are limited by their off-target activities on WT PI3Kα and other kinases, leading to significant side effects including hyperglycemia and rash.

RLY-2608 is an oral, mutant-selective PI3Kα allosteric inhibitor from Relay Therapeutics. Current FDA-approved PI3Kα modulator (alpelisib) and a clinically advanced molecule (inavolisib) are limited by their off-target toxicities associated with the inhibition of WT PI3Kα, leading to hyperglycemia and rash. RLY-2608 is currently in a Ph. I as a single agent and in combination with fulvestrant for HR+/HER2- breast cancer treatment. This article reviews the discovery of RLY-2608, its mechanism of mutant selectivity, how it compares to other molecules, recent clinical developments, and more.

AbbVie’s ABBV-467 is a highly potent, selective MCL-1 (myeloid cell leukemia-1) inhibitor which entered the clinic in 2022 in a Ph. I trial in patients with advanced hematologic cancers. MCL-1 has had a rough time in the clinic with multiple trials being halted or terminated due to cardiac toxicity, which is suspected to be an on-target effect. AbbVie’s approach with ABBV-467 was to target a highly potent/short half-life compound which could induce rapid apoptosis and tumor regressions in a short exposure period before the onset of any adverse events. Is this the end for MCL-1?

Sonrotoclax, BeiGene’s clinical-stage, orally bioavailable, next-generation inhibitor, targets both WT and mutated forms of the Bcl-2 protein by binding within a hydrophobic groove, similar to other inhibitors in its class. Explore this case study to see how sonrotoclax was rationally designed to potency against both WT and mutant Bcl-2 and address the limitations of first-generation inhibitors and more!