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.

EOS-984 is an oral, potential first-in-class, highly selective ENT1 inhibitor from iTeos currently in clinical trials for advanced solid tumors. The drug, which was identified through SBDD and optimization of the vasodilator dilazep, targets the immunosuppressive effects of adenosine, which helps tumors evade immune detection. This is an excellent case study on the importance of understanding a molecule's bioactive conformation to reduce the entropy of binding and enhance potency.

Inavolisib is a PI3Kα isoform-selective kinase inhibitor and monovalent degrader of the mutant p110α catalytic subunit of mutant PI3Kα. The molecule selectively depletes mutant p110α in cancer cells with active RTK (receptor tyrosine kinase) signaling and is in several ongoing or planned Ph. III trials for breast cancer. In October 2024, it received FDA approval for use in combination with palbociclib and fulvestrant to treat adults with endocrine-resistant, PIK3CA-mutated, HR+/HER2- breast cancer. This article explains how it works, how it was discovered, and why it matters.

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.

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.