The U.S. Food and Drug Administration (FDA) has approved VYKAT XR (diazoxide choline) extended-release tablets for the treatment of hyperphagia in adults and children aged 4 years and older with Prader-Willi syndrome (PWS). Developed by Soleno Therapeutics, Inc. (NASDAQ: SLNO), this approval marks a historic milestone as the first therapy specifically addressing the most debilitating aspect of PWS.
Soleno expects VYKAT XR, previously known as DCCR during its development phase, to be available to patients in the United States beginning in April 2025.
A Breakthrough for the PWS Community
Prader-Willi syndrome is a rare genetic neurodevelopmental disorder affecting approximately one in every 15,000 live births. The condition results from an abnormality in gene expression on chromosome 15 and is characterized primarily by hyperphagia—an insatiable hunger that significantly impacts quality of life.
"The approval of VYKAT XR is a significant milestone for Soleno and, most importantly, for the PWS community who have had no options to treat the most disruptive aspect of this disease," said Anish Bhatnagar, M.D., Chief Executive Officer of Soleno Therapeutics.
Hyperphagia in PWS manifests as an intense, persistent sensation of hunger accompanied by food preoccupations, an extreme drive to consume food, and a lack of normal satiety. These symptoms can lead to life-threatening complications including stomach rupture, choking, and accidental death due to food-seeking behavior. Long-term complications include diabetes, obesity, and cardiovascular disease.
Clinical Evidence Supporting Approval
The FDA approval was based on comprehensive clinical data, with efficacy established during a 16-week randomized withdrawal study period of Study 2-RWP (Study C602-RWP). This Phase 3 multi-center trial demonstrated that individuals randomized to switch to placebo showed statistically significant worsening of hyperphagia compared to those who remained on VYKAT XR.
Prior to the randomized withdrawal period, all study participants had received VYKAT XR in either double-blind or open-label settings for a mean duration of 3.3 years, providing substantial long-term safety data.
The safety profile of VYKAT XR has been well-established with over four years of data across four clinical studies. The most common adverse reactions occurring in ≥10% of individuals receiving VYKAT XR and at rates at least 2% greater than placebo included hypertrichosis, edema, hyperglycemia, and rash.
Impact on Patient Care
Jennifer Miller, M.D., Professor of Pediatric Endocrinology at the University of Florida, Gainesville, and a principal investigator in the VYKAT XR clinical development program, emphasized the significance of this approval: "I am excited to have VYKAT XR available to help treat hyperphagia, which is the most life-limiting aspect of PWS. Families of people with PWS have been prisoners in their own homes because of the need to provide constant, eyes-on supervision 24/7 with access to food being completely restricted."
The approval addresses a critical unmet need in PWS management. Until now, families have had to implement extreme measures to manage hyperphagia, including locking refrigerators and food cabinets, maintaining constant supervision, and restricting access to food—measures that significantly impact family dynamics and quality of life.
Patient Support and Access
Concurrent with the FDA approval, Soleno has launched Soleno One, a comprehensive patient support program to facilitate access to VYKAT XR. The program offers resources for patients, caregivers, and healthcare providers, with information available at VykatXR.com.
Healthcare providers can submit prescriptions through VykatXRHCP.com by completing a Start Form that initiates the treatment access process. The Soleno One support team is available toll-free at 1-(833)-SOLENO-1 (1-833-765-3661) from 8 a.m. to 8 p.m. ET Monday through Friday.
Advocacy Response
Patient advocacy organizations have welcomed the approval as a transformative development for the PWS community.
"Today marks a historic day for the PWS community. The FDA's approval of VYKAT XR represents a monumental step forward in addressing the longstanding unmet needs of individuals living with PWS and their families," said Stacy Ward, Chief Executive Officer of the Prader-Willi Syndrome Association | USA.
Susan Hedstrom, Executive Director of the Foundation for Prader-Willi Research, added: "This approval is a testament to the power of persistence, science, and advocacy. For years, families and researchers have worked towards a treatment option that truly addresses the complexities of PWS. Today, we take a major step forward in changing the future for individuals navigating hyperphagia associated with PWS."
Mechanism and Administration
VYKAT XR contains diazoxide choline, which is administered as a once-daily oral treatment. The medication carries specific warnings and precautions, including the potential for hyperglycemia and fluid overload. Healthcare providers are advised to monitor fasting plasma glucose and HbA1c before initiating treatment and regularly during therapy.
The drug is contraindicated in patients with known hypersensitivity to diazoxide, other components of VYKAT XR, or to thiazides. Complete prescribing information, including a medication guide, is available to healthcare providers.
Market Impact
As the first approved therapy specifically targeting hyperphagia in PWS, VYKAT XR enters an untapped market with significant unmet medical needs. While Soleno has not yet disclosed pricing information, the company is positioning the drug as a transformative therapy that could substantially improve quality of life for PWS patients and their families.
The approval represents a major commercial milestone for Soleno Therapeutics, which has focused its development efforts on rare disease therapeutics. VYKAT XR becomes the company's first commercially available product, potentially establishing Soleno as a significant player in the rare disease treatment landscape.
