NIDA-funded study evaluating extended-release injectable naltrexone + bupropion for the treatment of methamphetamine use disorder is published in NEJM.- Alkermes

Results from a National Institute on Drug Abuse (NIDA)-funded study evaluating the efficacy and safety of naltrexone for extended-release injectable suspension (XR NTX) administered once every three weeks plus oral extended-release bupropion administered daily as a combination treatment for adults with moderate or severe methamphetamine use disorder (MUD) were published by Dr. Madhukar H. Trivedi et al. in the New England Journal of Medicine (NEJM). This is the second published study evaluating this combination regimen for the treatment of MUD. The number of adults living with MUD has risen in recent years. In 2019, approximately 1 million adults in the U.S. reported having a methamphetamine use disorder—an increase of more than 50 percent since 2016. Currently, there are no FDA-approved medicines for the treatment of MUD. About the ADAPT-2 Study :The "Accelerated Development of Additive Pharmacotherapy Treatment (ADAPT-2) for Methamphetamine Use Disorder" study was a multi-site, double-blind, 12-week trial to evaluate the efficacy and safety of XR NTX (380 mg every three weeks) plus oral extended-release bupropion (450 mg/day) in adults with moderate or severe MUD. Participants (N=403) with moderate or severe MUD (defined as reported use on at least 18 of the 30 days prior to randomization) were randomized to combination therapy (XR NTX, 380 mg IM every three weeks, plus bupropion XL, up to 450 mg/d) versus placebo in a two-stage study. Placebo non-responders from stage 1 (6 weeks) were re-randomized in stage 2 for another 6 weeks. The primary outcome was the proportion of "responders," defined as having at least three methamphetamine-negative urine samples out of four samples obtained during weeks 5-6 (for stage 1) or weeks 11-12 (for stage 2). Response rates were higher with XR NTX plus bupropion than with placebo across both stages (overall weighted treatment effect of 11.1 percentage points; Wald z-test statistic = 4.53; p < 0.001; NNT =9), as well as in each stage [stage 1: (16.5% COMB vs. 3.4% PBO); stage 2: (11.4% COMB vs. 1.8% PBO)]. Secondary outcomes also favored treatment with XR NTX plus bupropion XL as compared to placebo. Adverse events in the combination treatment group included gastrointestinal disorders, tremor, malaise, hyperhidrosis, and anorexia. Serious adverse events occurred in 8 of 223 participants (3.6%) who received XR NTX plus bupropion in the study. Alkermes provided XR NTX and matched placebo free of charge for use in this trial under a written agreement with NIDA. See: Trivedi MH, Walker R, Ling, W, et al. "Bupropion and Naltrexone in Methamphetamine Use Disorder ". New England Journal of Medicine, 2021;384:140-53. DOI: 10.1056/NEJMoa2020214 .