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!

Morphic Therapeutic’s MORF-627 is an oral αvβ6 integrin inhibitor designed to treat IPF by blocking the TGFβ pathway. The Morphic team leveraged SBDD and FEP+ during lead optimization to enhance permeability and isoform selectivity. This article highlights the team’s focus on inhibiting the “bent-closed” conformation of αvβ6 as well as the linker design that led to the “chameloenicity” of the lead compound. The impressive multispecies PK and in vivo efficacy of MORF-627 in preclinical models was unfortunately accompanied by oncogenic toxicity that prevented it from reaching clinical trials.

KEAP1 inhibition/NRF2 activation has been hotly pursued in recent years for immunology indications; however, in oncology, NRF2 degradation has been posited as a novel therapeutic mechanism for specific cancers. Vividion has already disclosed work on covalent KEAP1 inhibitors, but at the recent ACS Fall 2024 meeting, the structure and discovery story of their clinical oral covalent activator of KEAP1 were disclosed, identified through careful analysis of the data from their inhibitor screen.

Revumenib (Revuforj®) is approved by the FDA as an oral, first-in-class menin-MLL interaction inhibitor for acute leukemia (AL). Since inhibition of the menin-MLL fusion protein interaction is selective for AL with a KMT2A translocation, it does not compromise normal hematopoietic function. This article covers the background, optimization and clinical development that has led to the approval of this groundbreaking new drug in a hard-to-treat indication.

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.