Amylyx pulls FDA-approved ALS drug after trial failure

Amylyx Pharmaceuticals is pulling its drug to treat amyotrophic lateral sclerosis (ALS) from the shelves after it failed in a confirmatory trial.

The company has started the process of discontinuing marketing authorizations for the drug, marketed as Relyvrio in the US and Albrioza in Canada. People who are already taking Relyvrio and believe it’s helping them can stay on it with the approval of a physician, but it will not be available to new patients.

Both the US Food and Drug Administration and Health Canada approved the drug in 2022 based on a 127-person Phase 2 clinical trial showing a functional benefit for patients with ALS. At the time, Amylyx had a larger, Phase 3 study underway that was meant to serve as a confirmatory trial. Amylyx co-CEOs Justin Klee and Joshua Cohen told regulators they would pull Reylvrio if it failed in Phase 3. “If the drug’s not helping patients, then why would we want to be giving it to them?” Klee said.

That’s what happened last month. In a 664-person study, Reylvrio did not meet any of its primary or secondary goals—including improvement in function, physical mobility, and communication—thus throwing its future into question.

“While this is a difficult moment for the ALS community, we reached this path forward in partnership with the stakeholders who will be impacted and in line with our steadfast commitment to people living with ALS and other neurodegenerative diseases,” Cohen and Klee said in a joint statement accompanying the firm’s announcement Thursday.

While Reylvrio doesn’t work in ALS, Amylyx plans to continue exploring the drug for other uses, including Wolfram syndrome and progressive supranuclear palsy. The company is also testing another drug, an antisense oligonucleotide that targets calpain-2, in ALS. But Amylyx will have fewer resources to move those forward after losing its main revenue stream in Relyvrio. The firm also announced that it is laying off 70% of its staff. That totals 269 employees, given that Amylyx had 384 full-time staffers at the end of 2023, according to its most recent annual filing.

“We commend Amylyx for pulling Relyvrio off the market, while still ensuring that people living with ALS can access the drug if they believe it is helping them,” the ALS Association says in a statement. “ALS is a fatal and heterogenous disease with few treatment options, and creative solutions are needed. We believe the example of Relyvrio shows how the system can work.”