The U.S. Food and Drug Administration has approved a new drug to treat Prader-Willi syndrome (PWS), marking the first available treatment for patients experiencing intense and persistent hunger. The drug, Vykat XR, developed by Soleno Therapeutics, addresses hyperphagia, a hallmark symptom of PWS caused by genetic deletions on chromosome 15, affecting gene expression regulation.
Prader-Willi syndrome is a rare genetic disorder that impacts around 50,000 people in the U.S. It affects various aspects of daily life, including eating habits, behavior, and mood. The symptoms of PWS appear at birth, with infants experiencing low muscle tone and difficulty in breastfeeding. As children grow, they develop hyperphagia, an insatiable feeling of hunger that typically begins around age four and persists into adulthood.
Starting in April 2025, Soleno Therapeutics will make Vykat XR available in the U.S. for patients aged four and older with PWS and hyperphagia. The drug, priced at an annual average cost of $466,200, will be dosed according to patient weight. The excessive hunger associated with PWS often leads to rapid weight gain, which, if uncontrolled, can result in obesity and related health complications such as respiratory issues and heart disease. The average lifespan of individuals with the condition is estimated to be between 21 and 29 years.
Vykat XR is a once-daily oral pill designed to target a specific brain pathway, reducing hyperphagia by decreasing the secretion of a peptide that regulates appetite. Its approval followed an extended review process and analysis of mixed results from late-stage trials. While a key trial involving 127 patients did not show a statistically significant difference in hyperphagia reduction compared to a placebo, further studies demonstrated that the drug significantly reduced hyperphagia in patients who continued treatment for at least a year.
The approval of Vykat XR has been long anticipated by patients and medical professionals. Many individuals with PWS struggle with constant thoughts about food and heightened anxiety around eating. These challenges often lead to disruptive food-related behaviors, including aggressive food-seeking.
Medical professionals who have worked closely with PWS patients emphasize the severe and unrelenting nature of hyperphagia. A specialist in pediatric endocrinology noted that patients frequently express how they never feel full, regardless of how much they eat. This persistent hunger significantly impacts their quality of life, making the availability of a treatment option a major milestone in PWS care.
The International Prader-Willi Syndrome Organisation has committed to working with Soleno Therapeutics and global health bodies to expand access to Vykat XR beyond the U.S. Efforts will focus on increasing awareness and advocating for broader availability of the drug worldwide. The introduction of this treatment marks an important step forward in managing PWS and improving the lives of those affected by the disorder.
