Idorsia drug fails to quell binge eating in midphase trial, driving biotech to abandon the indication

Idorsia has suffered another setback in the clinic. A phase 2a trial of the selective orexin-1 antagonist ACT-539313 in binge eating disorder missed the mark, prompting the Actelion spinout to give up on the indication. 

Switzerland-based Idorsia moved ACT-539313 into a midphase trial in the indication on the strength of a phase 1 study in healthy volunteers and animal data suggesting selective orexin-1 receptor antagonists can help with addictive behavior and disturbances related to stress and anxiety. However, the phase 2 study failed to translate the preclinical promise into humans. 

Investigators randomized 136 patients with moderate to severe binge eating disorder to receive placebo or 100 mg of ACT-539313 twice a day for 12 weeks. At the end of the treatment period, Idorsia assessed the change from baseline in the number of days per week on which the participants had at least one confirmed binge eating episode. 

By that key yardstick, ACT-539313 failed to beat placebo, causing the clinical trial to miss its primary endpoint. Idorsia is yet to share numbers from the study, but whatever the biotech learnt was dispiriting enough to drive it to abandon plans to bring the drug candidate to market in the indication. 

“The study confirmed the encouraging safety profile seen in the pharmacology studies, but it is clear that we will not pursue the binge eating disorder indication,” Alberto Gimona, head of global clinical development at Idorsia, said in a statement. 

Idorsia has kept ACT-539313 in its pipeline but changed its target indication from “binge eating disorder” to “under evaluation.” The biotech won approval for a dual orexin receptor antagonist, Quviviq, for use in patients with insomnia at the start of the year. Zeroing in on orexin-1 potentially opens up chances to treat addiction, anxiety, pain and obesity, but it remains to be seen whether Idorsia goes after the opportunities. 

The failure of the trial removes one of the few clinical milestones in a year skewed toward commercial progress for Idorsia. Data on the dual endothelin receptor antagonist aprocitentan in patients with high blood pressure are due around the middle of the year. Idorsia suffered setbacks to other programs late last year when lucerastat failed a phase 3 Fabry disease trial and cenerimod missed the primary goal in a phase 2b systemic lupus erythematosus study but still moved deeper into the clinic.