Nuvalent’s lead compound, NVL-520, is an oral, brain-penetrant, TRK-sparing, and potential best-in-class ROS1 kinase inhibitor that recently entered Ph. II of the ARROS-1 trial (NCT05118789) in patients with advanced ROS1-positive NSCLC. This article highlights what makes the Nuvalent’s NVL-520 program scientifically notable, including what gives it a potential best-in-class profile as a ROS1 inhibitor, the emerging toxicology of hard-to-avoid off-targets, an interesting synthetic route to the small macrocycle, and more.

Nested Therapeutics’ lead asset, NST-628, is an oral, brain-penetrant pan-RAF–MEK non-degrading molecular glue that lacks paradoxical pathway activation. Read the full article to learn about NST-628’s fascinating mechanism of action preventing paradoxical pathway activation, how it differentiates from other RAS/RAF/MAPK pathway inhibitors, the likely molecular origin, preclinical profile supporting clinical development, why this might be an ideal combination partner, and why this molecule is a big deal.

BMS-986365 is a potential best-in-class heterobifunctional ligand-directed degrader of WT AR. This full case study details how this heterobifunctional degrader was engineered to have low intrinsic agonism and exert direct antagonism of WT AR through occupancy of its ligand-binding domain, how the dual modality of BMS-986365 results in deep AR pathway inhibition and allows antagonism to reinforce degradation to combat compensatory resistance mechanisms, its attractive preclinical profile, interim clinical data, how it differentiates from Arvinas’ first-to-clinic AR degraders, and more!

Novartis’ HRO761 is an oral allosteric WRN helicase inhibitor, aimed at treating MSI-high and dMMR tumors. This article details the discovery of HRO761 and highlights the importance of selecting appropriate assays during early HTS as well as transferable medicinal chemistry strategies to optimize permeability and solubility through the modulation of LipE, neutral TPSA, chameleonicity, and non-classical zwitterions. It also explores the X-ray structure of HRO761 bound to WRN, how it differentiates from Vividion's VVD-214, its preclinical activity, clinical status, chemical synthesis, and more!

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.