---
title: "Acadia Pharma Faces Trial Setback As Prader-Willi Syndrome Trial Falls Short"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/258730699.md"
description: "Acadia Pharmaceuticals Inc. faced a setback in its Phase 3 COMPASS PWS trial for intranasal carbetocin in treating hyperphagia in Prader-Willi syndrome, as it failed to show significant improvement over placebo. Despite this, CEO Catherine Owen Adams expressed confidence in the company's future growth, projecting over $1 billion in net sales by 2025 and multiple upcoming studies. Following the trial results, ACAD stock dropped 11.02% in premarket trading."
datetime: "2025-09-24T14:05:05.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/258730699.md)
  - [en](https://longbridge.com/en/news/258730699.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/258730699.md)
---

> Supported Languages: [简体中文](https://longbridge.com/zh-CN/news/258730699.md) | [繁體中文](https://longbridge.com/zh-HK/news/258730699.md)


# Acadia Pharma Faces Trial Setback As Prader-Willi Syndrome Trial Falls Short

**Acadia Pharmaceuticals Inc.** ACAD released topline results on Wednesday from its Phase 3 COMPASS PWS trial evaluating the efficacy and safety of intranasal carbetocin (ACP-101) in patients with hyperphagia in Prader-Willi syndrome (PWS).

PWS is a rare genetic disorder characterized by muscle weakness and feeding difficulties in infancy, followed by an insatiable hunger and tendency toward severe obesity starting in childhood. PWS also involves delayed development, intellectual disability, behavioral issues and physical traits, such as short stature.

Intranasal carbetocin did not demonstrate a statistically significant improvement over placebo on the study’s primary endpoint, change from baseline to Week 12 on the Hyperphagia Questionnaire for Clinical Trials (HQ-CT), nor was there separation from placebo on any secondary endpoint.

**_Also Read: JPMorgan Lifts Acadia Price Target After Nuplazid Patent Victory_**

The safety and tolerability profile of intranasal carbetocin was consistent with previous clinical trials, showing a low rate of adverse events.

COMPASS PWS was a 12-week, double-blind, randomized, placebo-controlled global Phase 3 trial evaluating the efficacy and safety of intranasal carbetocin 3.2 mg three times daily (TID) in 175 enrolled children and adults aged five to 30 years with PWS.

“Despite this disappointment, Acadia is well-positioned to deliver long-term, sustainable growth supported by two approved products projected to generate over $1 billion in net sales in 2025, and a robust pipeline that includes eight disclosed and multiple undisclosed programs,” said **Catherine Owen Adams**, Acadia’s CEO. “Looking ahead, we anticipate seven Phase 2 or 3 study starts through 2026 and four data readouts by the end of 2027.”

Recently, a short report from **Scorpion Capital** alleged that the company’s rival**, Soleno Therapeutics Inc.’s** SLNO Vykat XR is overpriced and potentially unsafe for children with Prader-Willi syndrome (PWS).

**Price Action:** ACAD stock is down 11.02% at $21 during the premarket session at the last check on Wednesday.

-   **_Can Amazon’s New Delivery Plans Change How Brits Buy Groceries?_**

_Photo: Shutterstock_

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