Growth hormone looks set to remain the only approved product for hyperphagia, the insatiable hunger associated with Prader-Willi syndrome, after the latest failure in this tricky indication. Yesterday, Millendo Therapeutics joined Zafgen in announcing that its efforts here had come to naught, after both doses of its lead asset, livoletide, failed to beat placebo in a phase IIb trial. With no improvements in the secondary endpoints of reductions in body weight, fat mass or waist circumference, Millendo has not even been left with the get-out strategy of datamining for a subset of responders. With livoletide development effectively ended the field is now clear for Soleno Therapeutics’ project, a controlled-release form of diazoxide choline. Phase III data are expected in the first half of this year, though a delay owing to the Covid-19 pandemic cannot be ruled out. The sellside has pencilled in sales of $361m in 2024, according to consensus from EvaluatePharma. However, it is worth noting that the Destiny Prader-Willi study is the first placebo-controlled test of diazoxide choline CR, so expectations should probably be set accordingly.
|Selected Prader-Willi Syndrome products|
|Status||Project||Company||Mechanism of action||2024e sales ($m)|
|Marketed||Genotropin||Pfizer||GHRH receptor agonist||368|
|Phase III||Diazoxide choline CR||Soleno||ATP dependent potassium channel activator||361|
|Oxytocin receptor agonist||–|
|GLWL-01||GLWL Research||Ghrelin O-acyltransferase inhibitor||–|