EU Approves Acadia Pharmaceuticals' Rett Syndrome Drug Daybu

12:19 AM EDT, 08/25/2026 (MT Newswires) -- The European Commission granted marketing authorization to Acadia Pharmaceuticals' (DR6.F) Daybu, or trofinetide, for treating the neurobehavioral symptoms of Rett syndrome in adults and children aged five years and older. The authorization is backed by data from the phase 3 Lavender study, in which patients treated with Daybu showed statistically significant and clinically meaningful improvements in core features of Rett syndrome, according to a Tuesday release. The decision makes Daybu the first and only approved treatment for the neurobehavioral symptoms of Rett syndrome across the European Union, as well as Iceland, Liechtenstein and Norway.