Shares of Epizyme Inc. vaulted 75.5 percent Tuesday after the Cambridge biotechnology startup disclosed that an experimental cancer drug had performed well enough to earn a payout from the company’s partner, Celgene Corp.
News of the $25 million “proof of concept” milestone payment from Celgene, based in Summit, N.J., lifted Epizyme’s stock by $15.49 a share to $35.99 on the Nasdaq exchange.
Epizyme’s drug candidate, called EPZ-5676, is designed to treat genetically defined cancers.
The company said it had also earned a $4 million payment from the British pharmaceutical giant GlaxoSmithKline PLC for its work on a separate targeted cancer therapy.
A pioneer in the emerging field of “epigenetics,” Epizyme went public in June. Full story for BostonGlobe.com subscribers.
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