Soleno Therapeutics is breathing easier with a report from Acadia Pharmaceuticals that its candidate to treat hyperphagia in patients with Prader-Willi Syndrome (PWS) has come up short in a phase 3 trial.
The failure of Acadia to establish the efficacy of intranasal carbetocin—and the company's decision to scrap the treatment—leaves Soleno as the only company marketing a treatment for hyperphagia, an insatiable hunger condition that accompanies PWS.
Since March, when Redwood City, California-based Soleno captured an FDA approval for Vykat XR, sales have been brisk for the once-daily, extended-release tablet, which carries an annual list price of $466,200. In the second quarter, the company reported sales of $33 million for the potassium channel activator.
With the trial result, Soleno’s share price increased 11% by Wednesday afternoon while the price for Acadia tumbled by 9%.
Acadia had high hopes of bringing a medicine with a different mechanism of action to the market. But intranasal carbetocin failed to achieve the study’s primary endpoint, which was to show a statistically significant improvement on the Hyperphagia Questionnaire for Clinical Trials (HQ-CT) over placebo after 12 weeks of treatment.
The trial enrolled 175 children and adults ages 5 to 30 with PWS. Those in the treatment cohort received three 3.2-mg doses of intranasal carbetocin daily.
“We are committed to sharing a summary of the data in the future to ensure learning for the PWS community,” Elizabeth Thompson, Ph.D., Acadia’s R&D chief, said in a release. “However, given these results, we do not intend to investigate intranasal carbetocin any further.”
Acadia was hoping to offer another option for patients who are vexed by their insatiable appetite, often needing 24/7 supervision to prevent them from overeating.
San Diego-based Acadia, which was established in 1993, will carry on with two approved products that are expected to generate more than $1 billion in revenue this year, CEO Catherine Owen Adams said in a statement.
“Despite this disappointment, Acadia is well-positioned to deliver long-term, sustainable growth,” Adams said, adding that the company expects to start seven phase 2 or phase 3 trials next year, with four data readouts due by the end of 2027.
Acadia acquired intranasal carbetocin from Chicago's Levo Therapeutics in 2022 for just $10 million, shortly after another failed phase 3 study in the indication. Acadia believed it could succeed in its trial using a smaller dose over a longer treatment period.
An injected version of carbetocin was approved in Canada and the U.K. in 1997 to control bleeding after childbirth, particularly after cesarean section procedures. It was approved in several other countries but not in the U.S.