Arcus Biosciences recently disclosed the structure and discovery story of their oral HIF-2α inhibitor casdatifan (AB521) at the ACS Fall 2024 First Time Disclosures session in Denver. Read on to find out how the team overcame serum shifts and metabolism issues to deliver into the clinic what could potentially be a best-in-class compound, superior to the recently approved inhibitor, belzutifan.

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.

AZ-PRMT5i-1 is an orally bioavailable MTA-cooperative PRMT5 inhibitor that specifically targets MTAP-deleted cancers and is structurally related to AZ’s clinical candidate, AZ3470. This case study is an excellent example of utilizing bioisosteric replacements for polar guanidine headgroups, rigidifying scaffolds through spirocyclization to reduce rotatable bonds, and leveraging fluorine atoms beyond simply blocking metabolic soft spots.

HiberCell recently disclosed the discovery of HC-7366, a potential first-in-class, intentionally discovered, orally bioavailable, potent, selective, small-molecule kinase activator of GCN2. HC-7366 has now progressed to Ph. I trials to treat ccRCC and AML. This case study is a fantastic example of how to mitigate CYP3A4 inhibition and improve oral bioavailability via judicious choice of salt formulation.

BMS-986397 is a potential first-in-class CRBN-based selective CK1α molecular glue degrader. CK1α promotes tumor growth by enhancing MDM2 and MDMX degradation of the tumor suppressor p53. Since AML has a low TP53 mutation rate, activating the p53 pathway is a promising approach; however, p53 activators have faced challenges due to hematological toxicities. Targeting CK1α degradation offers an alternative approach. The BMS team sought to develop a CELMoD® for CK1α degradation. This article outlines the discovery of BMS-986397, as presented at the ACS Fall 2024 meeting in Denver, CO.