Abstract 5077: A novel small molecule menin-MLL inhibitor for potential treatment of MLL-rearranged leukemias

Abstract

Abstract Patients with MLL-rearranged leukemia typically have a poor prognosis. With chemotherapy and stem cell transplantation as current standard of care, the 5-year survival rate is estimated to be only about 35%. As the leukemogenic activity of MLL fusion proteins has been shown to be dependent on their direct interaction with menin, development of small molecules that block the menin-MLL interaction is a promising therapeutic strategy for the treatment of this disease. Although small molecule menin-MLL inhibitors have been reported, previously published compounds exhibited modest cellular potency and/or poor pharmacokinetic properties. We now describe a novel, potent, and selective small molecule menin-MLL inhibitor that effectively treats MLL leukemias in in vivo models and demonstrate its potential clinical utility. The compound selectively inhibits the growth of a panel of MLL-rearranged cell lines relative to non MLL-rearranged cell lines, displays favorable pharmacokinetic properties, and induces tumor regression in an MV4;11 subcutaneous xenograft mouse model, with durable tumor suppression even after dosing is discontinued. In both the MV4;11 and MOLM13 disseminated leukemia models, the compound confers a prolonged survival benefit compared to an untreated group when dosed orally once daily at doses that are well-tolerated in the animals. We have used this potent and selective menin inhibitor to investigate the functional cellular response of MLL-rearranged cell lines to menin inhibition, assessing cell growth, cell cycle and gene expression responses over time, and compared that response to other epigenetic inhibitors and demonstrate significantly increased apoptosis which correlates with tumor regression measured both in early and long term readouts in xenograft and systemic leukemia models. We describe a menin-MLL inhibitor with optimized drug-like properties that demonstrates potential clinical utility in preclinical models of MLL leukemias. The compound is currently under further preclinical evaluation. Citation Format: Tao Wu, Linda Kessler, Shuangwei Li, Trupta Purohit, Shisheng Li, Hongzhi Miao, Brian Linhares, Rasmus Hansen, Jeff Kucharski, Yi Wang, Ke Yu, Katarzyna Kempinska, Tess Ely, Szymon Klossowski, Ata Zarieh, Ulf Peters, Jun Feng, Yvonne Yao, Yuan Liu, Bo Wen, Francis Burrows, Duxin Sun, Jingchuan Zhang, Levan Darjania, Dana Hu-Lowe, Patrick Zarrinkar, Liansheng Li, Tomasz Cierpicki, Jolanta Grembecka, Pingda Ren, Yi Liu. A novel small molecule menin-MLL inhibitor for potential treatment of MLL-rearranged leukemias [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5077. doi:10.1158/1538-7445.AM2017-5077