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.

NDI-101150 is an oral HPK1 inhibitor discovered by Nimbus Therapeutics and is currently in Ph. I/II clinical trial in advanced solid tumors. HPK1 is a compelling immuno-oncology target due to its critical role in regulating T-cells, B-cells, and dendritic cell-mediated immune responses. HPK1-deficient mice demonstrate enhanced anti-tumor T-cell responses and resistance to tumor growth. In this article, we detail the discovery of NDI-101150, as highlighted by Nimbus at the ACS Fall 2024 First-Time Disclosures session, interim results from the clinic, and more.

BridgeBio’s BBO-8520 is a selective, covalent KRAS(G12C) inhibitor which differentiates itself from the pack by engaging the (ON) state of the protein, potentially conferring increased clinical benefit in KRAS(G12C)-driven cancers, including overcoming resistance to current treatments. Disclosed at the 2024 AACR Annual Meeting in San Diego, is currently in a Ph. I trial in patients with advanced non-small-cell lung cancer. This article covers the structure, mechanism of action and preclinical efficacy that marks this compound out as one to watch.

STX-478 is a wild-type-sparing, oral, CNS-penetrant, novel allosteric inhibitor of mutant phosphatidylinositol-3 kinase α (PI3Kα), 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.

Vorasidenib (AG-881) is a brain-penetrant allosteric inhibitor of mutant isocitrate dehydrogenases 1 and 2 (mIDH1/2) from Agios and Celgene that made headlines summer 2023 due to its stunning efficacy for treatment of glioma in patients with mIDH1/2. This Featured Case Study reviews how it was discovered, how it works, and why it matters.