Epizyme Earns $6-Million Milestone Payment From GlaxoSmithKline

“Epizyme has pioneered the discovery and development of epigenetic therapies for the treatment of cancer, with three agents discovered by Epizyme now in clinical development,” said Robert Bazemore, President and Chief Executive Officer, Epizyme. “Our collaboration with GSK represents an important part of our strategy of partnering with industry leaders to extend the breadth of our epigenetic therapies while providing resources to help us accelerate our portfolio of assets. We look forward to GSK’s continued progress with this program.”

GSK has initiated a Phase 1, dose-escalation study to investigate the safety, pharmacokinetics, pharmacodynamics and clinical activity of GSK3326595 in patients with solid tumors and non-Hodgkin lymphoma.

“The introduction of this PRMT5 inhibitor into the clinic by GSK is an exciting scientific achievement for Epizyme,” said Robert A. Copeland, Ph.D., President of Research and Chief Scientific Officer, Epizyme. “This milestone reinforces the strength of our scientific capabilities, which have enabled us to expand our platform into new epigenetic target classes of potentially high importance in oncology. Through our collaborations with GSK and other biopharmaceutical companies, as well as our in-house research efforts, we have developed a number of novel epigenetic programs that we believe hold tremendous potential, including this first-in-class PRMT5 inhibitor.”

About the Epizyme-GSK Collaboration
Under the terms of its collaboration and license agreement with GSK, Epizyme granted GSK exclusive worldwide license rights to methyltransferase inhibitors directed to three targets. During the research term of the collaboration, Epizyme was primarily responsible for pre-clinical research, and now GSK is responsible for subsequent research, development and commercialization of the three programs. Using its proprietary drug discovery platform, Epizyme discovered and optimized compounds targeting three methyltransferases, including PRMT5. GSK3326595 is the first of these to enter the clinic. GSK holds worldwide rights to all three programs. Epizyme has earned $59 million in up-front, research, and milestone payments to date, and may receive up to an additional $617 million from GSK if all milestones are met for all three programs. Epizyme is eligible to receive up to double-digit royalties on worldwide net sales of collaboration products.

About PRMT5 and GSK3326595
PRMT5 is a protein arginine methyltransferase (PRMT) that is reported to have a role in diverse cellular processes, including tumorigenesis. PRMT5 overexpression is observed in cell lines and primary patient samples derived from a number of cancers, including lymphomas, lung cancer, breast cancer and colorectal cancer. GSK3326595 (formerly EPZ015938), a highly selective and orally bioavailable small molecule, is the first PRMT5 inhibitor and the third epigenetic investigational therapy derived from Epizyme’s proprietary discovery platform to enter the clinic.

About Epizyme, Inc.
Epizyme, Inc. is a clinical-stage biopharmaceutical company creating novel epigenetic therapeutics for people with cancer. Epizyme has built a proprietary product platform to create small molecule inhibitors of chromatin modifying proteins (CMPs), such as histone methyltransferases (HMTs). CMPs are part of the system of gene regulation, referred to as epigenetics, that controls gene expression. Genetic alterations can result in changes to the activity of CMPs, making them oncogenic (cancer-causing). By focusing on the genetic drivers of cancers, Epizyme’s targeted science seeks to match the right medicines with the right patients. For more information, visit www.epizyme.com.