Pfizer Inc. PFE, -0.01% is ending ongoing research for a Duchenne muscular dystrophy drug after finding that the evidence "did not support a significant treatment effect," the company said on Thursday. Shares slumped 0.5% premarket, while shares of DMD drugmaker Sarepta Therapeutics Inc. SRPT, +0.56% rose 0.9%. Pfizer plans to keep reviewing trial data "to see if there is a place for this medicine in muscular diseases," said Seng Cheng, senior vice president and chief scientific officer, Pfizer Rare Disease Research Unit. Two phase 2 trials are being ended by Pfizer, and the decision was not made because of safety concerns about the therapy, domagrozumab, according to the company. DMD is a rare disease consisting of progressive muscle degeneration; the disease mostly affects boys and is often deadly. The first U.S. therapy for DMD, made by Sarepta, was approved in 2016. Pfizer is also developing a gene therapy for the disease, PF-06939926, which is in an ongoing clinical trial. Pfizer's stock has rallied 14.6% year to date through Wednesday, while Sarepta shares have soared 150.7% and the Dow Jones Industrial Average DJIA, -0.57% has gained 5.7%.
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