Phase III trial of SPN 812 meets primary endpoint in ADHD.- Supernus Pharmaceuticals.

Supernus Pharmaceuticals announced positive topline results from a pivotal Phase III study of SPN 812 in adolescents (P302) for the treatment of attention deficit hyperactivity disorder (ADHD). At daily doses of 200 mg and 400 mg, the trial met the primary endpoint with robust statistical significance in improvement in the symptoms of ADHD from baseline to end of study as measured by the ADHD Rating Scale-5. At the end of the study, SPN 812 200 mg and 400 mg doses reached statistical significance compared to placebo in the primary endpoint. Patients receiving SPN 812 200 mg and 400 mg had a -16.0 point change (p=0.0232) and a -16.5 point change (p=0.0091) from baseline, respectively, in the primary endpoint vs. -11.4 for placebo at week 6. This primary result, based on Mixed Model Repeated Measures (MMRM) analysis in the Intent-To-Treat (ITT) population, was confirmed by sensitivity analyses using Analysis of Covariance (ANCOVA) (200 mg, p=0.0163; 400 mg, p=0.0055). With respect to the effect size, patients receiving 200 mg and 400 mg had an effect size of 0.47 and 0.50, respectively, within the range of 0.46 to 0.63 observed in the first two Phase III studies and the Phase IIb study. The study demonstrated fast onset of action, reaching statistical significance for the 400 mg dose as early as week 1 with a p-value of 0.0085, and maintaining statistical significance on a weekly basis through the end of the trial at week 6.

Overall, the trial exhibited favorable tolerability and safety profiles with low incidence of AEs across all doses. AEs were mild leading to low discontinuation rates due to AEs of 1.9% to 4.1%. Treatment related AEs that reported at more than or equal to 5% for SPN 812 were somnolence, fatigue, decreased appetite, headache and nausea.

Comment: The Company expects to announce topline data from the final Phase III trial of SPN 812, study P304 in adolescents, by the end of the first quarter of 2019. The Company expects to submit a New Drug Application for SPN 812 in the second half of 2019, and to launch it, pending U.S. Food and Drug Administration approval, in the second half of 2020.