Pilot Study Suggests Efficacy of Naltrexone for Reducing Methamphetamine and Alcohol Craving and HIV Risk Behaviors Among Men Who Have Sex with Men

Methamphetamine use and heavy episodic drinking (> 5 drinks on a single occasion) are associated with HIV risk behaviors and are highly prevalent among men who have sex with men (MSM). This 8-week pilot study among 30 MSM with methamphetamine use (> 2 times per month) and heavy episodic drinking (but no diagnosis of DSM-IV dependence) and high-risk sexual behaviors evaluated the feasibility, acceptability, and tolerability of targeted naltrexone (i.e., during craving or in anticipation of methamphetamine or alcohol use), compared with placebo. All received one 15–20 minute session of substance use counseling every two weeks.

• Targeted naltrexone was found to be:
  • Feasible: trial completion rate was 93%; visit completion rate was 95%. There were no between-arm differences.
  • Acceptable: mean weekly number of medication pills taken was 2; patient satisfaction was 96%. There were no between-arm differences.
  • Tolerable: there were no serious adverse events in either treatment arm.
• While analyses revealed no differences in methamphetamine use or drinking overall, subgroup analyses revealed greater reductions in methamphetamine-using days among patients using > weekly receiving naltrexone compared with placebo (incidence rate ratio [IRR], 0.78), and greater reductions in heavy episodic drinking days among people who took >3 naltrexone pills in a week (IRR, 0.72).
• Patients in the naltrexone group were also found to have greater reductions in serodiscordant receptive anal intercourse (IRR, 0.15) and condomless receptive anal intercourse (IRR, 0.11).

Comments:

Given the prevalence of non-dependent methamphetamine use and heavy episodic drinking and associated HIV risk behaviors among MSM, the results of this study are of importance but are limited by the very small sample size. Much larger efficacy trials examining the impact of targeted naltrexone on substance use outcomes and sexual risk behaviors among this patient population are warranted.

Seonaid Nolan, MD

Reference:

Santos GM, Coffin P, Santos D, et al. Feasibility, acceptability and tolerability of targeted naltrexone for non-dependent methamphetamine using and binge-drinking men who have sex with men. J Acquir Immune Defic Syndr. 2015 [Epub ahead of print]. doi: 10.1097/QAI.0000000000000922.