title: Feasibility, Acceptability, and Tolerability of Targeted Naltrexone for Nondependent Methamphetamine-Using and Binge-Drinking Men Who Have Sex with Men.
abstract: BACKGROUND
  There are no effective pharmacologic strategies for nondependent methamphetamine (meth)-using and binge-drinking men who have sex with men (MSM) at high-risk for HIV. We sought to determine the feasibility of enrolling and retaining this population in a pharmacologic trial; the acceptability of pharmacotherapy study procedures; and the tolerability of targeted naltrexone versus placebo.
  
  
  METHODS
  Thirty meth-using and binge-drinking MSM were randomly assigned 1:1 to 50 mg naltrexone or placebo for 8 weeks for targeted administration (ie, during craving or in anticipation of meth or alcohol use). Substance use counseling and behavioral assessments were conducted every 2 weeks. Medication use was measured using WisePill dispensers.
  
  
  RESULTS
  Trial completion was 93%; visit completion rate was 95%. Mean weekly number of medication pills taken was 2.1 and was similar between arms. Participant satisfaction rate was 96%. There were neither serious adverse events nor differences in adverse event rates between arms. In exploratory intention-to-treat analyses, there were no differences in meth use and drinking. Naltrexone participants had greater reductions in serodiscordant receptive anal intercourse [incident rate ratio (IRR) = 0.15; 95% CI = 0.05 to 0.42] and serodiscordant condomless receptive anal intercourse (IRR = 0.11; 95% CI = 0.03 to 0.37), compared with placebo. In subgroup analyses among frequent meth users, naltrexone participants had greater reductions in meth-using days (IRR = 0.78; 95% CI = 0.62 to 0.99). In as-treated analyses, frequent study medication users in the naltrexone arm had greater reductions in binge drinking days (IRR = 0.72; 95% CI = 0.54 to 0.97).
  
  
  CONCLUSIONS
  Targeted naltrexone is a feasible, acceptable, and tolerable intervention strategy for nondependent meth-using and binge-drinking MSM. Naltrexone was associated with significant sexual risk reductions; and for some individuals, naltrexone was associated with meth and binge-drinking reductions.
authors.affiliation: *Center for Public Health Research Branch, San Francisco Department of Public Health, San Francisco, USA; †Department of Community Health Systems, University of California San Francisco, School of Nursing, San Francisco, USA; ‡Division of HIV/AIDS, University of California San Francisco, School of Medicine, San Francisco, USA; Departments of §Medicine; ‖Epidemiology and Biostatistics, and ¶Psychiatry, University of California San Francisco, School of Medicine, San Francisco, USA; and #San Francisco Veterans Affairs Medical Center, San Francisco, USA.
authors.forename: Glenn-Milo
authors.initials: GM
authors.lastname: Santos
authors.forename: Phillip
authors.initials: P
authors.lastname: Coffin
authors.forename: Deirdre
authors.initials: D
authors.lastname: Santos
authors.forename: Shannon
authors.initials: S
authors.lastname: Huffaker
authors.forename: Tim
authors.initials: T
authors.lastname: Matheson
authors.forename: Jason
authors.initials: J
authors.lastname: Euren
authors.forename: Anna
authors.initials: A
authors.lastname: DeMartini
authors.forename: Christopher
authors.initials: C
authors.lastname: Rowe
authors.forename: Judith A
authors.initials: JA
authors.lastname: Hahn
authors.forename: David
authors.initials: D
authors.lastname: Vlahov
authors.forename: Eric
authors.initials: E
authors.lastname: Vittinghoff
authors.forename: Steven L
authors.initials: SL
authors.lastname: Batki
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000517:prevention & control; D000293:Adolescent; D000328:Adult; D000368:Aged; D063425:Binge Drinking / Q000188:drug therapy*; D017280:Condoms / Q000706:statistics & numerical data; D003376:Counseling; D004311:Double-Blind Method; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D008694:Methamphetamine; D008875:Middle Aged; D009271:Naltrexone / Q000627:therapeutic use*; D009292:Narcotic Antagonists / Q000627:therapeutic use*; D010919:Placebos / Q000627:therapeutic use; D040242:Risk Reduction Behavior; D012309:Risk-Taking; D012725:Sexual Behavior / Q000187:drug effects; D019966:Substance-Related Disorders / Q000188:drug therapy*; D047568:Unsafe Sex; D055815:Young Adult
chemical_list: D009292:Narcotic Antagonists; D010919:Placebos; D008694:Methamphetamine; D009271:Naltrexone