FDA Extends Review Period for Soleno Therapeutics' DCCR Tablets in Prader-Willi Syndrome

Soleno Therapeutics, Inc., a clinical-stage biopharmaceutical company based in Redwood City, California, has announced that the U.S. Food and Drug Administration (FDA) has extended the review period for its New Drug Application (NDA) for DCCR (diazoxide choline) extended-release tablets. These tablets are intended to treat Prader-Willi syndrome (PWS) in individuals aged four and older who suffer from hyperphagia. The new Prescription Drug User Fee Act (PDUFA) target action date has been moved to March 27, 2025.

The FDA's decision to extend the review period by three months comes after determining that responses to recent information requests represent a major amendment to the NDA. This extension will provide the FDA additional time to thoroughly review the new information submitted. Importantly, the FDA did not raise any concerns regarding the safety, efficacy, or manufacturing of the drug in their correspondence.

Soleno submitted the NDA on June 27, 2024, and the FDA accepted it with Priority Review status in August 2024. The drug, diazoxide choline, has previously been granted Breakthrough and Fast Track Designations in the United States, as well as Orphan Drug Designation in both the U.S. and E.U. for treating patients with Prader-Willi syndrome.

Prader-Willi Syndrome (PWS) is a rare genetic disorder that occurs in approximately one in every 15,000 live births. The most notable symptom of PWS is hyperphagia, a chronic and life-threatening condition characterized by an insatiable hunger, food preoccupation, and an overwhelming drive to consume food. This symptom severely impacts the quality of life for those with PWS and their families. Other characteristics of PWS include behavioral issues, cognitive disabilities, low muscle tone, short stature (without growth hormone treatment), excessive body fat accumulation, developmental delays, and incomplete sexual development. Hyperphagia can lead to serious complications such as stomach rupture, choking, accidental death due to food-seeking behavior, and long-term conditions like diabetes, obesity, and cardiovascular disease. According to a global survey by the Foundation for Prader-Willi Research, a significant majority of respondents (comprising parents and caregivers) identified hyperphagia and body composition as critical symptoms needing treatment. Currently, there are no approved therapies to address hyperphagia or the metabolic, cognitive, and behavioral aspects of PWS.

DCCR (diazoxide choline) is an innovative extended-release tablet formulation containing diazoxide choline, designed to be taken once daily. Diazoxide, the parent molecule, has been used for many years in treating some rare diseases in neonates, infants, children, and adults, though it is not yet approved for PWS. Soleno has developed and secured extensive patent protection for the therapeutic use of diazoxide, diazoxide choline, and DCCR in PWS patients. The development program for DCCR is backed by data from five completed Phase 1 clinical trials involving healthy volunteers and three completed Phase 2 clinical trials, one of which included participants with PWS. In Phase 3 clinical trials for PWS, DCCR demonstrated potential in addressing hyperphagia and other symptoms such as aggressive behaviors, fat mass, and various metabolic parameters.

Soleno Therapeutics, Inc. focuses on developing and commercializing novel treatments for rare diseases. The company's lead candidate, DCCR (diazoxide choline) extended-release tablets, is currently under FDA review and has been granted Priority Review status.