Firm may pull ALS drug after failed trial

WASHINGTON — The maker of a much-debated drug for Lou Gehrig’s disease said Friday that its therapy failed to help patients in a large follow-up study, but it stopped short of committing to follow through on a prior pledge to pull the drug from the U.S. market.

The Food and Drug Administration approved Amylyx Pharmaceuticals’ Relyvrio in September 2022, following a yearslong advocacy campaign by patients with amyotrophic lateral sclerosis, or ALS, a fatal muscle-wasting disease.

Amylyx said it would discuss its plans for Relyvrio with patients and the FDA, which “may include voluntarily withdrawing” the drug. Executives were “surprised and disappointed” by the results and hoped to announce their plans in the next two months, they said in a statement.

The latest company study showed that the drug did not slow the disease compared with a dummy treatment. The drug also failed to show improvement on any secondary measures, such as muscle strength.

Amylyx’s medication is part of a string of drugs for deadly, degenerative diseases that have won FDA approval in recent years despite questionable proof that they work. The 2022 approval was based on results from one small, midstage study that was criticized by some of the agency’s own internal scientists. An outside committee of experts also voted against the drug initially, then were swayed to back it at a follow-up meeting requested by patients.

Company executives at the meeting told FDA regulators they would pull their drug from the market if a larger follow-up study didn’t confirm that it helps. That commitment seemed to reassure FDA’s advisers.