Physicians and experts on Prader-Willi syndrome issued new safety warnings about Neurocrine Biosciences’ newly approved Vykat XR. The experts said Vykat XR has been linked to seven deaths and more than 100 reports of serious adverse events, including hospitalizations for swelling and respiratory or heart complications. Regulatory data cited by the experts points to a post-marketing safety signal captured in the FDA Adverse Event Monitoring System, while the group emphasized that the deaths and severe events have not been definitively proven to be caused by the drug. Vykat XR was approved in March 2025 to curb intense hunger in PWS. The report increases scrutiny around prescribing and patient monitoring as regulators and clinicians continue to reconcile early post-approval safety outcomes with clinical risk-benefit assumptions.