FDA Approves Relyvrio for ALS Treatment

Yesterday, the FDA approved Relyvrio, an ALS drug developed by Amylyx Pharmaceuticals, after extensive discussions about the safety and efficacy of the drug. The drug was initially rejected by an FDA advisory panel in March of this year. Earlier this month, the panel reconvened and reanalyzed, voting in favor of Relyvrio after being presented with additional data. The final ruling was delivered yesterday, September 29, 2022.

“Today’s FDA approval of Relyvrio is an exciting milestone for the ALS community and is a major step toward achieving our mission to one day end the suffering caused by neurodegenerative diseases,” said Joshua Cohen and Justin Klee, Co-CEOs of Amylyx, in the company’s press release.

Unlike most FDA approvals, which follow two clinical trials, this approval was based on a relatively small phase II clinical trial. The 6-month randomized placebo-controlled trial recruited 137 participants. Based on the data collected from this trial, participants receiving Relyvrio had a slower decline in daily functioning.

The drug is composed of sodium phenylbutyrate and taurursodiol. Each packet comprises 3 g of sodium phenylbutyrate and 1 g of taurursodiol. It is taken orally or via a feeding tube by combining one packet with water. During the first three weeks of treatment, only one packet is recommended daily. After the three-week mark, the dose is increased to two packets per day.

Despite the benefits of the drug, some participants experienced side effects such as diarrhea, abdominal pain, nausea, and respiratory tract infection. While these adverse side effects can occur at any point during treatment, Amylyx states that they are most common in patients with pre-existing gastrointestinal disorders and typically occur within the first three weeks of treatment.

“This approval provides another important treatment option for ALS, a life-threatening disease that currently has no cure,” said Billy Dunn, MD, director of the Office of Neuroscience in the FDA’s Center for Drug Evaluation and Research in the FDA statement. “The FDA remains committed to facilitating the development of additional ALS treatments.”