Sarepta Therapeutics’ stock plummeted last week following an adverse event report (AER) of a serious side effect during a phase 2 gene therapy trial — but the company says the AER was wrongly submitted.

The sponsor says that neither it nor the trial’s principal investigator reported an adverse event involving a participant who experienced rhabdomyolysis, a breakdown of muscle tissue that releases a damaging protein into the blood.

The participant in Sarepta’s trial, which is testing a gene therapy candidate for Duchenne muscular dystrophy, was hospitalized for observation and determined to be asymptomatic.

The study’s drug safety monitoring board “has reviewed the issue and recommends the study continue uninterrupted,” the company said.