Naltrexone + Bupropion Combination for the Treatment of Binge-eating Disorder with Obesity: A Randomized, Controlled Pilot Study

Purpose: Binge-eating disorder (BED), the most prevalent eating disorder, is associated strongly with obesity and functional impairments. Few evidence-based treatments for BED exist; a pharmacotherapy effective in reducing both binge eating and weight needs to be identified. This placebo-controlled double-blind pilot RCT evaluated the acute effects of naltrexone + bupropion (NB) on BED with obesity and examined the longer-term effects through 6-month follow-up after the discontinuation of medication.

Methods: Twenty-two adult patients with BED were randomized to receive 12 weeks of double-blind treatment with fixed-dose NB (naltrexone + bupropion XL 50/300 mg) or placebo. Independent (blinded) researcher-clinicians evaluated patients at major outcome time points (baseline, posttreatment, and 6-month follow-up after the treatment period); patients were also evaluated for the tracking of course/tolerability throughout treatments and at 3-month follow-up. Primary outcomes were changes from baseline in binge-eating frequency and percentage weight. Secondary outcomes were changes in eating-disorder psychopathology and depression.

Findings: A total of 22 patients were enrolled (86.4% women; mean age, 50.4 years), with 77.3% of patients completing treatments; completion rates (NB, 83.3%; placebo, 70.0%) and adverse events did not differ significantly between NB and placebo. Analyses revealed significant reductions from baseline in binge-eating, eating-disorder psychopathology, depression, and weight during treatment, but these changes with NB did not differ significantly from those with placebo. The percentage of patients who attained 3% weight loss was significantly greater with NB than with placebo (45.5% vs 0%); weight-loss and binge-eating reductions were significantly correlated in the group that received NB. At 6-month follow-up, outcomes remained improved relative to baseline, with no significant differences between NB and placebo.

Implications: The findings from this pilot RCT suggest that NB was well-tolerated in these patients with BED and comorbid obesity. Most outcomes were not statistically different between NB and placebo. A larger-scale, adequately powered RCT is needed for determining the efficacy of NB in the treatment of BED. ClinicalTrials.gov identifier: NCT02317744.