Acadia Pharmaceuticals Inc (Nasdaq:ACAD), a developer of treatments for neurological and rare diseases, announced on Monday that the European Commission has granted marketing authorisation for DAYBU (trofinetide) to treat neurobehavioural symptoms of Rett syndrome in adults and children aged five and older.

This approval makes DAYBU the first and only treatment authorised for Rett syndrome in the European Union.

The decision was primarily supported by Phase 3 LAVENDER results, which showed statistically significant and clinically meaningful improvements in core Rett syndrome features based on the Rett Syndrome Behaviour Questionnaire (RSBQ) and Clinical Global Impression-Improvement (CGI-I) scale co-primary endpoints.

DAYBU is authorised for marketing across all 27 EU member states, as well as Iceland, Liechtenstein and Norway.

Acadia said it will begin pricing and reimbursement negotiations with national authorities as it works toward making the treatment available to patients across the region.