Epizyme, Inc., a company leading the discovery and development of personalized therapeutics for genetically-defined cancer patients, announced the achievement of pre-clinical milestones in its alliance with GlaxoSmithKline (GSK), triggering $4 million in milestone payments. Epizyme and GSK entered a worldwide strategic alliance in January 2011 to discover, develop, and market novel small molecule therapeutics targeting histone methyltransferases (HMTs), an important class of epigenetic enzymes, for the treatment of cancer and other diseases.

Robert Copeland, PhD, EVP and CSO of Epizyme, said: “The rapid progress we have made in our alliance with GSK provides further validation of Epizyme’s ability to discover small molecule histone methyltransferase inhibitors as personalized therapeutics for genetically-defined cancer patients.”

The GSK alliance leverages Epizyme’s unique HMT discovery platform, including its proprietary biology, biochemistry, chemical library, expertise, and intellectual property, to discover and develop HMT therapeutics against the set of targets included in the collaboration. Under the terms of the agreement, Epizyme received an upfront payment of $20 million and will also receive research funding. Epizyme is eligible to receive more than $630 million in total milestone payments if medicines are commercialized for all targets in the collaboration. Additionally, Epizyme is eligible to receive up to double-digit royalties on net sales of products resulting from the alliance. For each target in the collaboration, Epizyme will be primarily responsible for research up to development candidate selection, and GSK will be solely responsible for development and commercialization.

The HMT class of epigenetic enzymes contains 96 members, many of which have strong genetic associations with cancer and other serious diseases. Targeting HMTs with potent and selective small molecule inhibitors offers an innovative therapeutic approach to controlling pathways of disease-causing gene expression.