CAMBRIDGE, Mass., Aug. 27, 2025 (Business Wire) — Amylyx Pharmaceuticals, Inc. (NASDAQ: AMLX) said Wednesday it will discontinue its ORION program of AMX0035 for adults with progressive supranuclear palsy (PSP) after the drug showed no benefit over placebo in a mid-stage trial.
The Phase 2b study found no differences between AMX0035 and placebo on primary or secondary outcomes at Week 24. An open-label extension will also be halted, and the planned Phase 3 portion of the program will not move forward. Safety findings were consistent with earlier studies, with the drug continuing to be generally well-tolerated.
“We set a high bar for AMX0035 in PSP and made a commitment to base our decision-making on the totality of the data and the potential for clinically meaningful outcomes for those living with PSP,” said Camille L. Bedrosian, M.D., Chief Medical Officer at Amylyx. “While we are disappointed in these results, we believe these data will inform the PSP trial literature as well as deepen scientific understanding of this devastating disease. We extend our gratitude to the participants, their families and care partners, the ORION sites, and the entire PSP community for their collaboration on this study.”
Amylyx said its focus remains on other late-stage and early-stage programs. The pivotal Phase 3 LUCIDITY trial of avexitide is on track to complete enrollment in 2025, with topline results expected in the first half of 2026. Development of AMX0035 in Wolfram syndrome is ongoing, and the company is also advancing AMX0114 in ALS, with initial data from the Phase 1 LUMINA trial anticipated next year.
