A phase 2 trial of Opiant Pharmaceuticals’ naloxone nasal spray OPNT001 in bulimia nervosa has missed its primary and key secondary endpoints. The wipeout prompted Opiant to stop development of OPNT001 in the indication and double down on the rest of its pipeline.
Opiant’s rationale for testing OPNT001 in patients with the eating disorder rested on evidence of the effect opioid antagonists have on taste and food consumption. In other studies, drugs that block the action of opiates, such as naloxone, have been linked to reductions in the tastiness of food, the pleasure people take from eating and their preference for sweet and fatty foods.
That evidence contributed to Opiant’s decision to apply its nasal opioid delivery technology to the treatment of bulimia nervosa, and ultimately to the initiation of an 80-plus patient phase 2 trial designed to show that OPNT001 reduces binging.
The trial failed to deliver the hoped-for data. Participants who took OPNT001 daily for eight weeks had comparable numbers of binging days as subjects in the placebo cohort, resulting in the clinical trial missing its primary endpoint. The study also missed key secondary efficacy endpoints, leaving Opiant’s hopes for the program in tatters.
Opiant responded to the setback by stopping development of OPNT001 in bulimia nervosa. That leaves Opiant’s prospects resting on three other drugs, the most advanced of which is in late-phase development.
“The company’s focus for 2019 remains on conducting the pivotal trial for OPNT003, nasal nalmefene for opioid overdose, preparing to enroll patients into a phase 2 study for OPNT002, nasal naltrexone, for the treatment of alcohol use disorder and progressing the development of OPNT004, drinabant, for acute cannabinoid overdose,” Opiant CEO Roger Crystal said in a statement.
While the OPNT001 phase 2 was a washout in efficacy terms, it looks to have been free from safety concerns that could have suggested an underlying problem with the nasal-delivery technology that is central to Opiant’s other assets. Opiant said the drug “was generally safe and well-tolerated with minimal adverse events alongside good patient compliance.”