Positive Phase I results spark trial expansion stage
CAMBRIDGE, Mass.—Epizyme Inc. has released initial findings from its Phase I study of EPZ-5676, a selective inhibitor of the DOT1L histone methyltransferase under development for the treatment of acute leukemia with alterations in the MLL gene. So far, the treatment has been well tolerated and no dose-limiting toxicities have been observed, nor has the maximum tolerated dose been reached. Treatment effects consistent with the therapeutic mechanism of action were seen in half of the MLL-rearrangements (MLL-r) acute leukemia patients, though none were seen in the non-MLL-r patients. Treatment effects were consistent with leukemia cell differentiation and maturation, and some MLL-r patients reported resolution of leukemia-related symptoms and manifestations. As a result, a Phase I MLL-r only expansion stage will be started this December, with possible continued dose escalation.