Success with phase II study of trofinetide for Rett Syndrome

ACADIA Pharmaceuticals Inc., Neuren Pharmaceuticals Limited and Rettsyndrome.org (RSO) announced that the positive results from a Phase II study conducted by Neuren, which evaluated the safety and efficacy of trofinetide in females with Rett syndrome (RTT), have been published in Neurology, the medical journal of the American Academy of Neurology. The study, “Double-Blind, Randomized, Placebo-Controlled Study of Trofinetide in Pediatric Rett Syndrome” has been published online and will appear in the April 16, 2019 issue of Neurology. The study evaluated 82 females with Rett syndrome aged 5 to 15 years and found at the highest dose (200 mg/kg twice daily or BID) trofinetide achieved statistically significant improvement compared with placebo on three of five syndrome-specific efficacy measures: the Rett Syndrome Behaviour Questionnaire (RSBQ), a caregiver assessment (p=0.042), the Clinical Global Impression Scale-Improvement (CGI-I), a clinician assessment of the improvement of Rett syndrome (p=0.029), and the RTT-Clinician Domain Specific Concerns-Visual Analog Scale (RTT-DSC), a clinician assessment (p=0.025). Results of the study also showed trofinetide was well-tolerated at all dose levels (50 mg/kg BID, 100 mg/kg BID, and 200 mg/kg BID).

ACADIA plans to initiate a 12-week Phase III double-blind, randomized, placebo-controlled study evaluating trofinetide in the second half of 2019 following completion of additional manufacturing scale-up activities. This study will evaluate efficacy and safety of trofinetide and placebo in approximately 180 females ages 5 to 20 years with Rett syndrome. Half of the study participants will receive trofinetide and half will receive placebo. The study will use the RSBQ and the CGI-I syndrome specific efficacy measures as co-primary efficacy endpoints. The Phase III study will be followed by a nine month open label extension study in which all participants, including those on placebo in the Phase III study, will be eligible to receive trofinetide. In the open label extension study, all participants will be followed to evaluate long term tolerability and safety of trofinetide.

See; "Double-blind, randomized, placebo-controlled study of trofinetide in pediatric Rett syndrome"- Daniel G. Glaze, Jeffrey L. Neul, Walter E. Kaufmann, Elizabeth Berry-Kravis, Sean Condon, George Stoms, Sean Oosterholt, View ORCID ProfileOscar Della Pasqua, Larry Glass, Nancy E. Jones, Alan K. Percy First published March 27, 2019, DOI: https://doi.org/10.1212/WNL.0000000000007316.