Conditions: HIV Seroconversion Stimulant Abuse
Keywords: Methamphetamine Amphetamine Cocaine HIV Post-exposure prophylaxis HIV seronegativity
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 170
Healthy volunteers: yes

Brief summary:
This study seeks to evaluate the efficacy of a contingency management (CM) intervention compared to a yoked control condition for eliminating illicit stimulant use and for decreasing time to initiating post exposure prophylaxis (PEP), for improving adherence to PEP, and for completing PEP following a potential HIV-exposure event. Men who have sex with men who use cocaine amphetamine or methamphetamine frequently also have high risk sexual behaviors during or after their drug use. The objective of this study evaluates whether the use of CM that targets stimulant use significantly aids men who have sex with men who use stimulants and also engage in high-risk sexual transmission behaviors to be able to initiate, adhere to and complete PEP, thereby optimizing the utility of a biomedical HIV prevention intervention for reducing HIV incidence in this very high-risk group of MSM.

Detailed description:
This was a prospective, randomized study. 170 participants who met inclusion and exclusion criteria were randomized to CM or NCYC (non-contingent yoked-control condition) arms. They were provided with a 4-day starter-pack of PEP medication (tenofovir + emtricitabine, Truvada) to be started only in the event of a high-risk sexual exposure. The two interventions were implemented simultaneously:

The CM or NCYC intervention, remunerating (via vouchers) the participant based on his own (CM) or a yoked-participant's (NCYC) stimulant-metabolite-free urine samples for 8 weeks;

and,

Post-exposure prophylaxis, providing risk reduction counseling, adherence counseling and PEP medication for 28 days in the event of a high-risk sexual exposure to HIV.

All participants were followed for 24 weeks, or 24-weeks post-HIV-exposure, whichever was longer.

Arms:
arm 1: Participants will submit a urine sample every Monday, Wednesday, and Friday for 8 weeks (a total of 24 urine samples). Samples will be tested for stimulant metabolites. Increasingly valuable incentives will be provided for urine samples that lack metabolites of stimulant drugs.

Participants reporting recent (i.e., \< 48 hours) exposure to HIV viral inoculum will have the opportunity to initiate Truvada (1 pill daily for 28 days). arm 2: Participants will submit a urine sample every Monday, Wednesday, and Friday for 8 weeks (a total of 24 urine samples). Samples will be tested for stimulant metabolites. Incentives will be provided to participants independent of stimulant drug use and determined in the same rate and timing as a randomly selected participant in the active CM condition.

Participants reporting recent (i.e., \< 48 hours) exposure to HIV viral inoculum will have the opportunity to initiate Truvada (1 pill daily for 28 days).

Interventions: intervention 1: Truvada
Intervention descriptions: intervention 1: Truvada At qualifying exposure, participants will take 28 days' worth (at one pill per day) of 200 mg emtricitabine and 300 mg tenofovir DF (Truvada).

Protocol document: