AIM: To examine the safety and efficacy of modafinil (200 mg/day) compared to placebo in the treatment of methamphetamine dependence and to examine predictors of post-treatment outcome.
PARTICIPANTS AND DESIGN: Eighty methamphetamine-dependent subjects in Sydney, Australia were allocated randomly to modafinil (200 mg/day) (n = 38) or placebo (n = 42) under double-blind conditions for 10 weeks with a further 12 weeks post-treatment follow-up.
MEASURES: Comprehensive drug use data (urine specimens and self-report) and other health and psychosocial data were collected weekly during treatment and research interviews at baseline, week 10 and week 22.
RESULTS: Treatment retention and medication adherence were equivalent between groups. There were no differences in methamphetamine abstinence, craving or severity of dependence. Medication-compliant subjects tended to provide more methamphetamine-negative urine samples over the 10-week treatment period (P = 0.07). Outcomes were better for methamphetamine-dependent subjects with no other substance dependence and those who accessed counselling. There were statistically significant reductions in systolic blood pressure (P = 0.03) and weight gain (P = 0.05) in modafinil-compliant subjects compared to placebo. There were no medication-related serious adverse events. Adverse events were generally mild and consistent with known pharmacological effects.
CONCLUSIONS: Modafinil demonstrated promise in reducing methamphetamine use in selected methamphetamine-dependent patients. The study findings support definitive trials of modafinil in larger multi-site trials.