HealthDay News — For adults with methamphetamine use disorder, response is higher with receipt of extended-release injectable naltrexone plus oral extended-release bupropion versus placebo, according to a study published in the Jan. 14 issue of the New England Journal of Medicine.
Madhukar H. Trivedi, M.D., from the University of Texas Southwestern Medical Center in Dallas, and colleagues conducted a multisite trial with use of a sequential parallel comparison design. Adults with moderate or severe methamphetamine use disorder were randomly assigned to receive either naltrexone-bupropion or matching injectable and oral placebo for six weeks. Those in the placebo group with no response in stage 1 were randomly reassigned to receive naltrexone-bupropion or placebo for an additional six weeks (stage 2). The primary outcome was a response, defined as at least three methamphetamine-negative urine samples out of four samples.
Overall, 403 participants were enrolled in stage 1 and 225 were enrolled in stage 2. The researchers found that 16.5 percent of the naltrexone-bupropion group and 3.4 percent of the placebo group had a response in the first stage; 11.4 and 1.8 percent, respectively, had a response in the second stage. Across the two stages, the weighted average response was 13.6 and 2.5 percent for naltrexone-bupropion and placebo, respectively, for an overall treatment effect of 11.1 percentage points.
“Replication of our trial results in a more naturalistic effectiveness design could be a next step,” the authors write.
Several authors disclosed financial ties to pharmaceutical companies, including Alkermes, which provided Vivitrol and matching placebo free of charge for use in this trial.