Soleno Therapeutics, Inc. announced positive top-line results from the randomized withdrawal period of Study C602, a long-term treatment study of DCCR (Diazoxide Choline) Extended-Release tablets for the treatment of Prader-Willi syndrome (PWS). The FDA previously acknowledged that data from this study have the potential to support an NDA submission for DCCR, which has Orphan Drug designation for the treatment of PWS in the U.S. and E.U. and Fast Track designation from the FDA. The multi-center, randomized, double-blind, placebo-controlled randomized withdrawal period enrolled 77 patients previously enrolled in Study C602 who had been on open-label treatment with DCCR for between two and four years.

Participants were randomized 1:1 to receive either DCCR (n=38) or placebo (n=39) for a period of four months. The primary endpoint was the change from baseline in hyperphagia-related behaviors as assessed by the hyperphagia questionnaire for clinical trials (HQ-CT), a caregiver-com completed nine item validated questionnaire for assessing hyperphagia in PWS. Secondary endpoints included investigator assessments of participants' overall severity of illness and change in condition, as measured by Clinical Global Impression of Severity (CGI-S) and Clinical Global Impression of Improvement (CGI-I) ratings, respectively.