SAN DIEGO — Acadia Pharmaceuticals Inc. (Nasdaq: ACAD) said the U.S. Food and Drug Administration has approved DAYBUE STIX (trofinetide) for oral solution, a new dye- and preservative-free powder formulation for the treatment of Rett syndrome in adult and pediatric patients two years of age and older.
DAYBUE STIX is designed to deliver the same efficacy and safety profile as DAYBUE oral solution while offering patients and caregivers greater flexibility in dosing volume and taste. Acadia said DAYBUE and DAYBUE STIX are currently the only FDA-approved treatments for Rett syndrome, a rare neurodevelopmental disorder.
“DAYBUE, the first and only approved treatment for Rett syndrome, has provided thousands of patients an important therapeutic option,” said Catherine Owen Adams, Chief Executive Officer of Acadia Pharmaceuticals. “With the approval of DAYBUE STIX, we are building on our commitment to turn scientific promise into meaningful innovation by introducing a new formulation informed by invaluable feedback from patients, caregivers and healthcare providers.”
Clinicians said the new formulation adds flexibility in patient care. Jennifer Martelle Tu, M.D., Ph.D., Director of Katie’s Clinic for Rett Syndrome and Associate Professor of Neurology at UCSF Benioff Children’s Hospitals in Oakland, said the powder formulation allows caregivers to mix the medication with a variety of water-based liquids to better manage taste and dose volume.
“The new formulation gives us an additional option for treatment with DAYBUE, allowing us to better customize care for our patients,” Tu said. “DAYBUE STIX is a powder for oral solution that caregivers can mix with a variety of water-based liquids providing flexibility to modify the taste and volume of their loved one’s dose. We know that this kind of adaptability is something many Rett families have been seeking.”
Acadia said the efficacy and safety of DAYBUE STIX are supported by data from the LAVENDER study of DAYBUE oral solution in patients with Rett syndrome. Approval of the new formulation was based on results from a bioequivalence study demonstrating comparable exposure between the oral solution and the powder formulation, indicating similar efficacy and safety.
DAYBUE STIX is expected to be available on a limited basis beginning in the first quarter of 2026, with broader availability planned for early in the second quarter of 2026. The existing DAYBUE oral solution formulation will remain available.
