Acadia's Daybue Wins EU Regulatory Backing for Rett Syndrome After Re-Examination
Key Insights
The CHMP has issued a positive opinion recommending EU approval of Acadia's Daybue (trofinetide) for Rett syndrome (search) following a successful re-examination after an initial rejection in February.
If approved by the European Commission, Daybue would become the first therapy specifically authorized in the EU for the neurobehavioral symptoms of Rett syndrome (search).
Acadia's Q1 2025 Daybue revenue reached $101 million, representing 20% year-over-year growth, and the company's 2028 sales guidance of $700 million includes European revenue.
Acadia Pharmaceuticals' drug Daybue (trofinetide) has received a positive recommendation from the European Medicines Agency's human medicines committee, the CHMP, following a re-examination of the company's data. The decision marks a significant turnaround after the same committee voted against marketing authorization in February, and now positions the therapy for final approval by the European Commission within 67 days.
The drug, which will be marketed under the brand name "Daybu" across the 27 EU member states, is designed to treat the neurobehavioral symptoms of Rett syndrome (search), a rare genetic disorder that affects brain development and coordination. The U.S. Food and Drug Administration first approved trofinetide for pediatric patients and adults with Rett syndrome in 2023.
"The CHMP's positive opinion for Daybu is an important milestone in our mission to bring this innovative therapy to the EU, where there are no therapies specifically approved for the neurobehavioral symptoms of this devastating condition," said Acadia CEO Catherine Owen Adams in a statement.
Market and Financial Implications
The regulatory momentum has already moved markets. Acadia's shares rose as much as 12% in morning trading on the news, pushing the stock back within sight of its 52-week high. Mizuho analyst Uy Ear noted in a client communication that Acadia's 2028 sales guidance of $700 million includes a "modest amount" of European revenue, suggesting the Wall Street consensus forecast of $595 million may be too conservative.
During the first fiscal quarter of 2025, Daybue generated $101 million in revenue, reflecting 20% year-over-year growth. Acadia's other approved product, Nuplazid for psychosis related to Parkinson's disease and Alzheimer's, contributed $167 million in the same period. With a market capitalization under $5 billion, Acadia maintains a narrow focus on underserved rare neurological conditions and faces little to no real competition for Daybue in the Rett syndrome (search) space.
Broader CHMP Decisions
The CHMP committee also took action on several other notable therapies during the same session. The committee voted to revoke the approval of Amgen's Tavneos for two rare inflammatory conditions affecting blood vessels due to the risk of serious side effects. Amgen's commercial partner Kissei reported that 20 people have died after receiving the treatment in Japan, most from vanishing bile duct syndrome (search).
In positive decisions, the committee voted to expand use of Eli Lilly's BTK (search) inhibitor Jaypirca across all lines of chronic lymphocytic leukemia (search), based on data presented at the American Society of Hematology meeting in December. Additional expansions included AstraZeneca and Daiichi Sankyo's antibody-drug conjugate Datroway for first-line triple-negative breast cancer (search) in patients ineligible for immunotherapy, Johnson & Johnson's bispecific antibody Tecvayli for second-line multiple myeloma (search), and Incyte's Opzelura for atopic dermatitis (search), representing a major expansion from its current indication in vitiligo.