(Reuters) – Sarepta Therapeutics Inc said on Monday the U.S. Food and Drug Administration declined to approve its newest treatment for Duchenne muscular dystrophy (DMD), citing safety concerns including the risk of infection and kidney toxicity.
Shares of the company plunged 12.7% to $105.05 in trading after the bell.
Sarepta acknowledged that kidney toxicity was observed in animal trials, which tested the drug, golodirsen, in doses “ten-fold higher” than those tested on humans.
However, the side effect was not observed in the human trial on which the application for approval was based, the company said.
“We are very surprised to have received the complete response letter this afternoon,” Chief Executive Officer Doug Ingram said in a statement.
“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,” Ingram said.
Duchenne muscular dystrophy is a progressive disorder that begins to cause symptoms at an early age, first by hampering the ability to walk and later by causing breathing difficulties and heart problems.
Many patients die at a relatively young age from DMD, which is caused by the absence of dystrophin, a muscle building protein.
Exondys 51, the company’s first DMD treatment, was approved in 2016 against the advice of the FDA’s outside panel of experts and its own reviewers, who had questioned the drug’s effectiveness.
The company said it would request a meeting with the FDA to determine next steps for golodirsen.
Reporting by Manas Mishra and Nivedita Balu in Bengaluru; Editing by Anil D’Silva