Acadia Pharmaceuticals discontinued development of ACP-101, an intranasal therapy aimed at mitigating hyperphagia in patients with Prader-Willi syndrome (PWS), after its 12-week phase III trial failed to show statistically significant improvements over placebo. The decision removes a potential competitor to Soleno Therapeutics’ Vykat XR, currently the only FDA-approved drug for hyperphagia in PWS. This setback underscores the ongoing challenges in addressing this rare genetic disorder’s complex behavioral symptoms.