Identifying Predictors of Weight-Related Outcomes With Fixed-Dose, Extended-Release Naltrexone and Bupropion Among Treatment-Adherent Patients in Phase 3 COR Trials: A Treatment Target Analysis.

Objective: As patient response to obesity medication can vary, it is crucial to identify both those likely and unlikely to respond to treatment. This post hoc analysis aimed to examine predictive characteristics in patients who achieved weight-related targets with fixed-dose, extended-release combination of naltrexone and bupropion (NB-ER). Methods: This pooled analysis included patients from three Phase 3, placebo-controlled COR trials (NCT00532779, NCT00567255, NCT00456521). The impact of baseline characteristics in predicting changes in weight-related anthropometric targets at 56 weeks in those who completed treatment and were ≥ 90% adherent to NB-ER was evaluated with univariable and multivariable analyses. Results: Of the 1692 patients analyzed, similar proportions of patients receiving NB-ER versus placebo were female and White. Among patients treated with NB-ER with ≥ 90% adherence, 73.2% achieved ≥ 5% body weight (BW) reduction, 47.6% achieved ≥ 10% BW reduction, 27.8% achieved ≥ 15% BW reduction, 33.7% achieved target body mass index, and 23.7% achieved target waist circumference thresholds. Among the baseline characteristics assessed, female sex and White race most consistently predicted the likelihood of achieving the target outcomes. Conclusion: Adherence to NB-ER was associated with achieving anthropometric targets; however, the ability to predict a successful response in advance of NB-ER treatment is still limited.