Sarepta Therapeutics Inc. said the U.S. Food and Drug Administration rejected its application for golodirsen to treat Duchenne muscular dystrophy.
DMD is a genetic disorder characterized by progressive muscle degeneration and weakness.
The regulator issued a complete response letter for the drugmaker's new drug application for golodirsen injection to treat DMD in patients with a gene mutation that is amenable to exon 53 skipping. Golodirsen is designed to bind to a specific section of the gene that causes DMD, causing that section to be "skipped" so that the gene then codes for a functional protein.
Cambridge, Mass.-based Sarepta said the FDA was concerned about the risk of infections related to intravenous infusion ports and kidney-related toxicity seen in preclinical models of golodirsen. The company added that kidney toxicity with the drug was seen in preclinical models at doses 10x higher than those in clinical studies. Further, kidney toxicity was not observed in study 4053-101, which was the basis for the application.
Sarepta President and CEO Doug Ingram said the company was "very surprised" with the rejection. "Over the entire course of its review, the agency did not raise any issues suggesting the non-approvability of golodirsen, including the issues that formed the basis of the complete response letter," he said in an Aug. 19 news release.
The company said it will request a meeting with the FDA to determine next steps.
Sarepta's Essence study, or 4045-301, evaluating golodirsen and casimersen, another of its "skipping agents," is ongoing.
Shares of Sarepta dropped by 16% at market open Aug. 20 to $100.43, and were trading about 13% down as of 10:07 a.m. at $103.81.
