Real world efficacy of naltrexone/bupropion for weight management in obesity and after bariatric surgery

Abstract Background Insufficient weight loss or weight regain after metabolic and bariatric surgery (MBS) is frequent, and the evidence to support the use of pharmacotherapy for weight management is limited. Methods In this single-centre retrospective cohort study, the effectiveness of naltrexone/bupropion (NB) for weight control in surgery-naive and post-MBS patients was evaluated. Data was collected between 2016 and 2022 on all consecutive patients started on NB after multidisciplinary consult. Patients received weekly dose escalation up to 32/360 mg daily per the manufacturer’s protocol, with submaximal doses administered in cases of adverse effects or sufficient therapeutic response. Weight evolution, metabolic status, adherence and adverse events were analysed at 4 and 12 months after NB initiation. Data are presented as median (interquartile range). Results A total of 153 patients initiated NB therapy, including 111 who were surgery-naive, and 42 with prior MBS. The median time after MBS was 7.7 years (4.3, 15.3). Among the post-MBS patients, 18 (42.9%) patients had undergone Roux-en-Y gastric bypass and 11 (26.2%) sleeve gastrectomy. At 4 months after initiation of NB, 46.8% of the surgery-naive patients and 66.7% of the post-MBS patients remained using NB, with a median weight loss of 6.4% (3.0, 10.1) and 6.1% (2.4, 2.0) respectively. At 12-months, 38.5% of surgery-naive patients and 60.7% of post-MBS patients had continued NB, with median weight loss of 8.8% (5.0, 16.7) and 11.1% (4.7, 19.8) respectively. There was no statistically significant difference in weight loss between the surgery-naive and post-MBS group. Weight loss was not significantly influenced by whether the maximal dose was reached in both the surgery-naive patients (p = 0.38) and the post-MBS patients (p = 0.61). Conclusion Real-world data show that NB treatment is equally effective in surgery-naive patients and in patients experiencing weight regain after bariatric surgery, regardless of the maximal dose administered.