Genentech announced that fenebrutinib (GDC-0853), a non-covalent BTK inhibitor entering Ph. III, showed significant human CNS exposure and reduced new brain lesions in Ph. II for relapsing multiple sclerosis. Fenebrutinib is the only reversible BTK inhibitor in Ph. III for MS, and has the opportunity to differentiate on safety relative to covalent inhibitors. This case study highlights notable challenges overcome in the discovery of fenebrutinib including surprising metabolism, animal-specific on-target toxicity, and more.

The Bristol Myers Squibb (BMS) HPK1 kinase inhibitor, “compound 24” is an oral tool compound intended for cancer immunotherapy, with >50x selectivity against family members including GLK. The starting point was an IRAK4 kinase inhibitor identified from historical kinome selectivity data. A homology-model based on MST1 was used for [...]

Sovleplenib (HMPL-523) is an orally bioavailable Syk inhibitor being developed by HUTCHMED and is currently in Ph. II and Ph. III clinical trials for several autoimmune diseases. Derived from an HTS hit and SAR optimization, the discovery story of sovleplenib serves as an excellent case study on how to design a next-generation Syk inhibitor devoid of off-target kinase activity, mitigated hERG activity, and more.

A second-generation AR bifunctional degrader for drug-resistant prostate cancer. ARV-766 is Arvinas’ second bifunctional CRL4 CRBN E3 ligase-based androgen receptor (AR) degrader to enter the clinic for the treatment of prostate cancer (PCa), after ARV-110 (bavdegalutamide) . The glutarimide recruiting element is notable as it is simpler than [...]

Kymera's KT-474 is the first oral degrader to demonstrate activity in clinical trials outside cancer and Sanofi recently started a Ph. II trial with the molecule in AD, restoring life to IRAK4 as an immunology target. This article highlights why Kymera’s KT-474 program is scientifically notable, including how it differentiates from small molecule inhibitors, potential competitiveness with biologics, the first reported cryo-EM ternary complex of a heterobifunctional degrader, and why this 2023 Molecule of the Year Nominee will likely be considered a “landmark in drug discovery” for some time.