March 4 (Reuters) – PepGen said on Wednesday that the U.S. Food and Drug Administration has placed a partial clinical hold on its mid‑stage trial of a rare muscle disease drug, sending its shares plunging over 25% in extended trading.
The drug, PGN‑EDODM1, is being tested for myotonic dystrophy type 1, a genetic disease that causes muscles to weaken and tighten over time, making movement and daily activities harder.
PepGen said the health regulator’s concerns relate to earlier laboratory and animal studies the company submitted.
The agency did not flag any safety concerns from patient data generated in an early-stage study.
PepGen said it is working with the FDA to address the questions and will submit additional information, including newly unblinded data from the earlier study.
While the U.S. portion of the trial is on hold, the company has been cleared to open the study in South Korea, Australia and New Zealand.
Patients in the UK and Canada are already being treated at the 10 mg/kg dose, following a recommendation from an independent safety board to move ahead with dose escalation.
No patients in the U.S. had been enrolled in the trial before the hold was placed.
PepGen said it had $148.5 million in cash and investments as of December 31, 2025, enough to fund its operations into the second half of 2027.
(Reporting by Kamal Choudhury in Bengaluru; Editing by Sahal Muhammed)
