RMC-9805 is a first-in-class, covalent KRAS(G12D)(ON) molecular glue inhibitor from Revolution Medicines that uses a cyclophilin A (CypA)-recruiting tricomplex mechanism combined with a finely tuned aziridine covalent handle to inhibit the previously “undruggable” KRAS(G12D) mutant. Read our coverage of the discovery story, disclosed at the AACR 2024 meeting in San Diego, to discover how structural and modeling insights were key to engaging a poorly nucleophilic mutant Asp, how RMC-9805 synergizes with PD-1 inhibitors, and the progress this remarkable compound is making in the clinic.

PLX-4545 is an oral CRBN-based molecular glue degrader of IKZF2 in Ph. I trials. It potentially addresses anti-tumor immunity suppression within the TME, critical in checkpoint blocker resistance. Tumors use IKZF2 to regulate the function of regulatory T cells and inhibit effector T cells. IKZF2 depletion in regulatory T cells enhances the anti-tumor response. The discovery and structural data of PLX-4545 were presented by Kevin Freeman-Cook at the ACS Fall 2024 First-Time Disclosures session in Denver, CO. We are reporting the discovery story and its potential impact on immuno-oncology.

In August 2024, seladelpar (LivdelziTM) became the first FDA-approved selective agonist of PPARδ (peroxisome proliferator-activated receptor δ), following an almost 20-year journey from the original discovery and patent publications. Originally developed by CymaBay in collaboration with Johnson & Johnson, approval was granted to Gilead Sciences following their February 2024 purchase of CymaBay Therapeutics for $4.3B. Seladelpar was approved as a second-line treatment for patients with primary biliary cholangitis.

Pfizer disclosed the structure and discovery of their oral small molecule BDK inhibitor/degrader, PF-07328948, during the ACS Fall 2024 First-Time Disclosures session in Denver. The team identified a thiophene carboxylic acid-based hit targeting an allosteric pocket on BDK. Through optimization, they overcame challenges such as potential IADRs and BDK-E2 complex stabilization. By manipulating the dihedral angle of the methoxy group, they enhanced binding interactions, verifying PF-07328948's unexpected mechanism of action in vivo. PF-07328948 is currently Ph. I trials.

The recently released WHO INN proposed names list includes the structure and name of Structure Therapeutics’ oral small molecule GLP-1R agonist, aleniglipron (GSBR-1290). Seemingly emerging from a “fast-follower” program based on Chugai/Eli Lilly’s orforglipron, the compound includes an unusual phosphine oxide motif and has shown positive results on plasma glucose levels and bodyweight in a Ph. IIa study.