Just weeks after GlaxoSmithKline committed up to $650 million in its epigenetics pact with Cambridge, Mass.-based Epizyme, Japan's Eisai has joined the promising discovery platform with a $206 million collaboration of its own, according to Fierce Biotech.

Like most discovery deals, it starts small—with a $6 million upfront payment—while holding out $200 million at the back end as the two companies target EZH2, an epigenetic enzyme, for the treatment of lymphoma and other cancers in genetically-defined patients.

"Eisai is committed to bringing epigenetic therapeutics to cancer patients," said Takashi Owa, president of the oncology product creation unit at Eisai Product Creation Systems. "Epizyme's proprietary product platform, leadership in determining the oncogenic role of EZH2 in genetically-defined cancers, and success in discovering novel, potent and selective small molecule inhibitors of histone methyltransferases (HMTs), an important epigenetic target class, led us to them as the partner of choice in epigenetic drug discovery." 

Eisai will fund 100% of R&D through human proof-of-concept, at which point Epizyme has the right to opt into a profit share and co-commercialization arrangement for the U.S.

Robert Gould, Epizyme CEO, said the "U.S. profit share and co-commercialization option is a key element of our strategy to discover, develop and also to commercialize epigenetic medicines.”