The Menarini Group, a leading international pharmaceutical and diagnostics company headquartered in Italy, and Stemline Therapeutics, Inc., a wholly-owned subsidiary of the Menarini Group focused on bringing transformational oncology treatments to cancer patients, along with clinical stage generative artificial intelligence (AI)-driven biotechnology company Insilico Medicine (based in the US and Hong Kong), have entered into an exclusive licensing agreement granting Stemline the global rights to develop and commercialise a novel, small molecule KAT6A inhibitor designed using Insilico's AI platform, as a potential treatment for hormone sensitive cancers and other oncology indications. 

KAT6A is known to play an important role in several cancers. Overexpression of KAT6A correlates with poor clinical outcomes in patients with ER+/HER2- breast cancer, the most common subtype of breast cancer.  In preclinical studies, the molecule has demonstrated potent inhibition against KAT6A in multiple cell line-derived xenograft (CDX) and patient-derived xenograft (PDX) models with good efficacy and safety. 

The novel molecule was designed by Insilico's R&D team with the help of its end-to-end Pharma Generative AI platform to inhibit KAT6A and block endocrine receptor (ER) at the transcriptional level, giving it the potential to overcome resistance to endocrine therapies due to mutation or ligand-independent constitutive activation of ER. Currently, endocrine therapy in combination with CDK4/6 inhibitors is the standard treatment for ER+/HER2- breast cancer patients with advanced or metastatic disease. Novel combinations with CDK4/6 inhibitors and/or new oral SERDs are needed to further extend outcomes.

Under the terms of the agreement, Stemline will provide a $12 million upfront payment to Insilico. The combined value of the deal, including all development, regulatory, and commercial milestones, is over $500 million, followed by royalties up to double digits.