A.L.S. Drug Relyvrio Will Be Taken Off the Market, Its Maker Says

The maker of the newest treatment approved for amyotrophic lateral sclerosis said Thursday that it would withdraw the drug from the market because a large clinical trial did not produce evidence that the treatment worked.

The company, Amylyx Pharmaceuticals, said in a statement that it had started the process of withdrawing the drug in the United States, where it is called Relyvrio, and in Canada, where it is called Albrioza. As of Thursday, no new patients will be able to start the drug, while current patients who wish to continue taking the medication can be transitioned to a free drug program, the company said.

The medication is one of only a few treatments for the severe neurological disorder. When the Food and Drug Administration approved it in September 2022, the agency concluded there was not yet sufficient evidence that the medication could help patients live longer or slow the progression of the disease.

It decided to greenlight the medication anyway, instead of waiting two years for results of a large clinical trial, citing data showing the treatment to be safe and the desperation of A.L.S. patients. The disease robs patients of their ability to control muscles, speak and breathe without assistance and often causes death in two to five years.

Since then, about 4,000 patients in the United States have received the treatment, a powder that is mixed with water and either drunk or ingested through a feeding tube. Its list price was $158,000 a year.

Last month, Amylyx, of Cambridge, Mass., announced that the results of a 48-week trial of 664 patients showed that the treatment did not work better than a placebo. The company said then that it would consider withdrawing the drug from the market.