Grilo 2021: naltrexone-bupropion for binge eating with obesity, a pilot trial

What they tested

Twenty-two adults with binge-eating disorder and obesity were randomly assigned to 12 weeks of naltrexone plus extended-release bupropion (50 mg and 300 mg) or a placebo, a dummy pill. Neither patients nor staff knew who got which.

The main outcomes were changes in how often people binge ate and in percentage weight. Researchers who didn't know the group assignments assessed people at the start, at the end of treatment and 6 months after the medicine stopped.

What they found

Binge eating, eating-disorder symptoms, depression and weight all fell from where they started, but the drops on naltrexone-bupropion were not significantly different from those on placebo.

Significantly more people lost at least 3% of their weight on the combination: 45.5% vs 0%. In the medicine group, people who lost more weight also tended to cut binge eating more.

77.3% completed treatment (83.3% on naltrexone-bupropion and 70.0% on placebo), and side effects did not differ significantly between the groups.

Six months after treatment ended, people were still better off than at the start, with no significant differences between the groups.

Limits

• With 22 people it was a pilot, and the authors say a larger, adequately powered trial is needed to judge whether the combination works.
• Most participants were women (86.4%), and all had obesity as well as binge-eating disorder.

What it means if you're considering naltrexone

This trial is about binge eating, not alcohol. Most results on naltrexone-bupropion matched placebo, so it adds little support for the pair as a binge-eating treatment, though the medicines were tolerated and helped more people reach at least 3% weight loss.