Bupropion for the treatment of methamphetamine dependence in non-daily users: A randomized, double-blind, placebo-controlled trial

Aim: Bupropion was tested for efficacy to achieve methamphetamine (MA) abstinence in dependent, non-daily users. Methods: A randomized, double-blind, placebo-controlled trial, with 12-week treatment and 4-week follow-up, was conducted with 204 treatment-seeking participants having MA dependence per DSM-IV, who used MA on a less-than-daily basis. 104 were randomized to matched placebo and 100 to bupropion, sustained-release 150 mg, twice daily. Participants were seen three times weekly to obtain urine for MA and bupropion assays, study assessments, and thrice weekly, 90-min, group psychotherapy. There was no biomarker for placebo adherence. The primary outcome was achievement of abstinence throughout the last two weeks of treatment; 'success' requiring at least two urine samples during each of Weeks 11 and 12, and all samples MA-negative (<300 ng/mL). Results: Bupropion and placebo groups did not differ significantly in the percentage achieving abstinence for the last 2 weeks of treatment (chi-square, p = 0.32). Subgroup analysis of participants with lower baseline MA use (<= 18 of last 30 days before consent) also revealed no difference in success between groups (p = 0.73). Medication adherence per protocol (detectable bupropion, >5 ng/mL, in >= 50% of urine samples from Study Weeks 1-10 and >= 66% of urine samples from Weeks 11 to 12) was achieved by 47% of participants taking bupropion. Conclusions: These data indicate that bupropion did not increase abstinence in dependent participants who were using MA less-than-daily. Medication non-adherence was a limitation in this trial. Psychosocial therapy remains the mainstay of treatment for MA dependence. Further research on subgroups who may respond to bupropion may be warranted. Published by Elsevier Ireland Ltd.