Arvinas’ ARV-393 is an orally bioavailable PROTAC that degrades BCL6 via CRBN-mediated ubiquitination and proteasomal degradation intended for the treatment of NHL. At the AACR San Diego 2024 meeting, Arvinas disclosed the structure and discovery story of this molecule, which exhibits first-in-class potential. This article covers the key SAR observations that led to the invention of this orally bioavailable PROTAC®, its performance in a triple-hit, high-grade BCL and R-CHOP-resistant cell line, and why sustaining BCL6 knockdown beyond 24 hours was critical for the success of this program.

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.

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.

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.