clinicaltrials.gov Identifier: NCT00099983.

Aim Modafinil was tested for efficacy in decreasing use in methamphetamine-dependent participants, compared to placebo. Methods This was a randomized, double-blind, placebo-controlled study, with 12 weeks of treatment and a 4-week follow-up. Eight outpatient substance abuse treatment clinics participated in the study. There were 210 treatment-seekers randomized, who all had a DSM-IV diagnosis of methamphetamine dependence; 68 participants to placebo, 72 to modafinil 200mg, and 70 to modafinil 400mg, taken once daily on awakening. Participants came to the clinic three times per week for assessments, urine drug screens, and group psychotherapy. The primary outcome measure was a methamphetamine non-use week, which required all the week's qualitative urine drug screens to be negative for methamphetamine. Results Regression analysis showed no significant difference between either modafinil group (200 or 400mg) and placebo in change in weekly percentage having a methamphetamine non-use week over the 12-week treatment period (p=0.53). Similarly, a number of secondary outcomes did not show significant effects of modafinil. However, an ad-hoc analysis of medication compliance, by urinalysis for modafinil and its metabolite, did find a significant difference in maximum duration of abstinence (23 days vs. 10 days, p=0.003), between those having the top quartile of compliance (>85% urines modafinil +, N=36), and the lower three quartiles of modafinil 200 and 400mg groups (N=106). Conclusions Although these data suggest that modafinil, plus group behavioral therapy, was not effective for decreasing methamphetamine use, the study is probably inconclusive because of inadequate compliance with taking medication.

Aims Topiramate has shown efficacy at facilitating abstinence from alcohol and cocaine abuse. This double-blind, placebo-controlled outpatient trial tested topiramate for treating methamphetamine addiction. Design Participants (N=140) were randomized to receive topiramate or placebo (13 weeks) in escalating doses from 50 mg/day to the target maintenance of 200 mg/day in weeks 6–12 (tapered in week 13). Medication was combined with weekly brief behavioral compliance enhancement treatment. Setting The trial was conducted at eight medical centers in the United States. Participants One hundred forty methamphetamine-dependent adults took part in the trial. Measurements The primary outcome was abstinence from methamphetamine during weeks 6 – 12. Secondary outcomes included use reduction versus baseline, as well as psychosocial variables. Findings In the intent-to-treat analysis, topiramate did not increase abstinence from methamphetamine during weeks 6–12. For secondary outcomes, topiramate reduced weekly median urine methamphetamine levels and observer-rated severity of dependence scores significantly. Subjects with negative urine before randomization (N=26) had significantly greater abstinence on topiramate versus placebo during study weeks 6–12. Topiramate was safe and well tolerated. Conclusions Topiramate does not appear to promote abstinence in methamphetamine users but can reduce the amount taken and reduce relapse rates in those who are already abstinent.

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Aims 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 150mg, twice daily. Participants were seen three times weekly to obtain urine for MA and bupropion assays, study assessments, and thrice weekly, 90-minute, 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 (<300ng/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, >5ng/mL, in ≥50% of urine samples from Study Weeks 1–10 and ≥66% of urine samples from Weeks 11–12) 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. Trial Registration www.ClinicalTrials.gov : NCT00687713.