Mosaic Therapeutics Ltd, a targeted oncology therapeutics company dedicated to resolving cancer’s complexity with new combination therapies for patients, has in-licensed two clinical-stage oncology programs from Astex Pharmaceuticals, a wholly owned subsidiary of Otsuka Pharmaceutical Co. Ltd.

Mosaic has identified proprietary combinations incorporating the licensed products and their targets and this agreement gives Mosaic the exclusive rights to develop those combination products for patients for whom there are no or limited treatment options.

As part of the agreement, Astex has taken an equity stake in Mosaic equating to a fully-diluted ownership stake of 19% equity upfront and a further 3% dependent on clinical milestones, which will consolidate the partnership between these two innovation-driven businesses. Astex will also receive potential future revenue shares. Dr. Harren Jhoti, Co-founder, President and Chief Executive Officer of Astex, will also take an observer role on the Mosaic Board. Other financial details have not been disclosed.

Mosaic’s platform identifies oncology drug pairs predicted to have synergistic activity in biomarker-defined populations, leading to greater efficacy than monotherapy. The strategy is to seek a broad, biomarker-defined label across multiple tumor types. The two assets from Astex are ASTX029, an ERK1/2 inhibitor that completed a Phase 2 study, and ASTX295, an MDM2 antagonist developed with the Cancer Research UK Drug Discovery Unit, which completed a Phase 1 study. Both licensed compounds have been studied in over 100 patients and show differentiated safety profiles and single-agent activity, enabling combination therapies.

“Mosaic’s mission is to bring novel targeted combination medicines to patients who need them,” said Dr. Edward Hodgkin, Managing Partner of Syncopal Investment Management Limited and Chair of Mosaic. “The in-licensing of these two clinical-stage assets provides a step change in our development pipeline, allowing Mosaic to progress targeted drug combinations in novel biomarker-defined settings and enabling the delivery of precision medicines for patients who currently have few therapeutic options. Excitingly, the deal significantly accelerates Mosaic’s development path, with the first clinical combination study expected to commence in 2026.”

“We recognize the significance of Mosaic’s platform, which has identified these two assets as anchor components of a pipeline of potential combination products,” said Dr. Harren Jhoti, Co-founder, President and CEO of Astex. “Both drug targets are well-characterized drivers of many cancers, and we are excited to be working with the experienced team at Mosaic to expand the Company’s pipeline in combination therapies with high unmet medical need.”