Clinical report: takeaways from Amylyx’s ALS journey

After a high-drama development program that involved not one but two advisory committee meetings, an approval based on Phase II results that FDA’s own reviewers found unconvincing, and a public promise from the company to voluntarily withdraw the therapy if its Phase III trial was negative, the story of the ALS drug from Amylyx may be coming to an end. The question now is what can be learned from the experience.

Amylyx Pharmaceuticals Inc. (NASDAQ:AMLX) announced Friday that Relyvrio, its fixed-dose combination of sodium phenylbutyrate and taurursodiol, missed the primary and secondary endpoints in the Phase III PHOENIX trial to treat amyotrophic lateral sclerosis. The company also acknowledged that Relyvrio failed to show benefit in a subgroup of patients who matched the inclusion criteria used in the company’s Phase II that formed the basis of the drug’s approval...