Highlights

  • Neuren shares declined sharply following regulatory update on trofinetide’s EU review process.
  • European regulator signaled a negative trend vote after reviewing Rett syndrome treatment application.
  • Acadia plans to seek formal re-examination under established European regulatory procedures.

Neuren Pharmaceuticals Limited (ASX:NEU) shares closed at AUD 14.44, falling 11.17 percent, on 3 February after its licensee, Acadia Pharmaceuticals Inc., released an update on the European regulatory status of trofinetide. The decline followed disclosure of a negative trend vote issued by the European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP).

The update relates to Acadia’s marketing authorization application (MAA) for trofinetide as a treatment for Rett syndrome within the European Union.

Details of the CHMP Review Process
According to the announcement, the CHMP informed Acadia of the negative trend vote following an oral explanation provided during the evaluation process. While the vote does not represent a final decision, it signals that the committee is currently inclined toward issuing a negative opinion on the application.

Under European Union regulations, Acadia retains the right to request a re-examination of the CHMP opinion once it is formally adopted. If exercised, this process involves submitting grounds for review within prescribed timelines, after which the committee has up to 60 days to reassess its position.

Next Procedural Steps in Europe
Acadia has indicated that, subject to the outcome of the February CHMP vote, it intends to request a re-examination of the opinion. This step is part of the standard regulatory framework and allows applicants to respond to concerns raised during the initial assessment.

Neuren confirmed its support for the re-examination process, citing the breadth of clinical and real-world experience accumulated for trofinetide across multiple regions.

Global Regulatory Status of Trofinetide
Trofinetide is already approved for the treatment of Rett syndrome in the United States, Canada, and Israel. The therapy is marketed in the United States under the brand names DAYBUE and DAYBUE STIX, following approval by the US Food and Drug Administration.

Neuren has granted Acadia exclusive global rights for the development and commercialization of trofinetide. As of the latest update, more than 1,000 patients worldwide are receiving active treatment, spanning pediatric and adult populations.

Broader Pipeline Context
Beyond trofinetide, Neuren is advancing NNZ-2591, a separate drug candidate under development for several rare neurodevelopmental disorders. Phase 2 trials have reported positive results in conditions including Phelan-McDermid syndrome, Pitt Hopkins syndrome, and Angelman syndrome. Each program has received orphan drug designation in both the United States and the European Union.