Abstract 1813: Discovery, biomarker validation, and pre-clinical profiling of a novel PKMYT1 inhibitor

Abstract Protein kinase membrane-associated tyrosine/threonine 1 (PKMYT1) is a negative regulator of CDK1 activity and has been identified as a putative synthetic lethal target in cancers which upregulate cyclin E (CCNE1). We used high-throughput virtual screening to identify inhibitors of PKMYT1 with high lipophilic ligand efficiency (LLE), which were rapidly optimized to potent leads with exceptional selectivity over a key off target, WEE1. Machine learning-driven optimization rapidly reduced mouse hepatocyte clearance to acceptable levels, delivering a compound with best-in-class potency, selectivity, and pharmacokinetic profiles in relevant animal models. Tool compounds from this series were used to validate a differentiated biomarker for sensitivity to PKMYT1 inhibition in cellular models, which could significantly expand the potential patient population. In vivo proof-of-concept studies are ongoing in a variety of cell line- and patient-derived xenograft models which represent the novel biomarker previously identified, to further validate our therapeutic strategy. Citation Format: Alfie Brennan, Jan Lanz, Daniel S. Miller, Oliver Vipond, Noah Harrison, James Aaronson, Anna Hercot. Discovery, biomarker validation, and pre-clinical profiling of a novel PKMYT1 inhibitor abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 1813.