Acadia Pharmaceuticals Ends Prader-Willi Drug Development After Trial Failure

What's Happening?

Acadia Pharmaceuticals has ceased development of its investigational drug for hyperphagia in Prader-Willi syndrome following a late-stage trial failure. The Phase III COMPASS PWS trial tested intranasal carbetocin, an oxytocin analogue, but failed to meet its endpoints, showing no significant change in hyperphagia symptoms. Acadia acquired the drug, ACP-101, from Levo Therapeutics in 2022, which had previously faced FDA rejection for the drug. Despite higher enrollment in the COMPASS trial, the results were insufficient to demonstrate clinical efficacy. Acadia plans to share trial data with the Prader-Willi community but will not pursue further development of intranasal carbetocin.

Why It's Important?

The discontinuation of ACP-101 development marks a setback for Acadia in addressing Prader-Willi syndrome, a rare neurological condition with severe cognitive effects. The failure highlights the challenges in developing effective treatments for rare diseases and the importance of robust clinical trial design. Acadia's decision impacts its portfolio strategy, shifting focus to other pipeline projects, such as ACP-204 for Alzheimer's-related psychosis. The trial failure also affects investor confidence, as reflected in a 12% drop in Acadia's share price. The pharmaceutical industry may redirect attention to alternative treatments for Prader-Willi syndrome.

What's Next?

Following the trial failure, Acadia is likely to concentrate on its other drug development programs, particularly ACP-204, with a Phase II readout expected in mid-2026. The company may also explore partnerships or acquisitions to bolster its pipeline. The Prader-Willi community will await Acadia's data summary to gain insights into the trial outcomes. Meanwhile, industry focus may shift to other potential treatments for Prader-Willi syndrome, as companies seek to address unmet needs in this area.