Orphan drug shows promise in Prader-Willi syndrome

Ten weeks of therapy with a diazoxide choline controlled-release tablet appeared to help control hyperphagia and reduce antisocial behaviors associated with Prader-Willi syndrome, according to a press release from the drug’s developer, Essentialis, Inc.

Diazoxide choline was granted orphan status for the treatment of Prader-Willi syndrome (PWS) by the FDA in May of last year.

Participants in the randomized withdrawal study PC025 were patients with genetically confirmed PWS between 10 and 22 years old (mean age, 16 years) with obesity (52% body fat) and moderate hyperphagia. The five female and eight male patients were initially treated with diazoxide choline controlled-release (DCCR) for 10 weeks and then randomly assigned to continue treatment or placebo for 4 more weeks.

After the initial 10-week treatment phase, average body fat reduction was 4.2% (P = .003), lean body mass increase was 4.9% (P = .005), and the increase in the ratio of lean body mass to fat mass 9.8% (P = .002). In addition, hyperphagia decreased by 35% (P = .006). In participants who exhibited aggressive, threatening and destructive behaviors at baseline, these had stopped 62.5% of the time (P = .01; for the comparison to the rate of cessation of all other PWS associated behaviors 29.8%). The most common adverse event was peripheral edema.

"We have proceeded from a working hypothesis on why DCCR should have an impact on PWS to having clearly shown that DCCR is therapeutically effective. I view it as a very promising therapeutic option for the treatment of PWS," Virginia Kimonis, MD, of the University of California Irvine School of Medicine, said in the release. "We look forward to the conclusion of this study next month, providing patients with expanded access to DCCR and to completing the planning for the pivotal study."