Biobehavioral Interventions for HIV-negative, Stimulant Using Men Who Have Sex With Men

Phase 2

Completed

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.

Recruitment & Eligibility

Inclusion Criteria

Male who has sex with other men (MSM) by self-report
At least 18 years of age
HIV-negative serostatus on baseline rapid oral HIV antibody test, and no signs or symptoms consistent with primary HIV infection (PHI)
Self-reported stimulant use within the previous 30 days
Self-report of unprotected anal intercourse (either receptive or insertive) with an HIV-positive or status unknown partner within the previous 3 months
Self-report of no previous hypersensitivity to any of the components of Truvada (tenofovir disoproxil fumarate or emtricitabine)
In the opinion of the study medical provider, no contraindication to PEP medication treatment (laboratory testing, medical/drug interaction, or other)
Has not used PEP in the previous 6 months
A current resident of Los Angeles County
Does not have a plan to move away from Los Angeles County in the next 6 months
Willing and able to provide informed consent
Willing and able to comply with study requirements

Exclusion Criteria

Does not identify as a male who has sex with other men
Under 18 years of age
HIV positive by self-report or as indicated by the results on baseline rapid oral HIV antibody testing
Has not used a stimulant in the previous 30 days by self-report
Has not had unprotected anal intercourse (either receptive or insertive) with an HIV-positive or status unknown partner within the previous 3 months
Creatinine clearance <30 ml/min and not on dialysis
Self-reports any previous hypersensitivity to any of the components of Truvada (tenofovir disoproxil fumarate or emtricitabine);
In the opinion of the study medical provider, there exists a contraindication to administering Truvada-based post-exposure prophylaxis (laboratory testing, medical/drug interaction, or other)
Has used PEP in the previous six months
Not a current resident of Los Angeles County
Unwilling or unable to provide informed consent
Unwilling or unable to comply with study requirements

Arm && Interventions

Group	Intervention	Description
Contingency Management	Truvada	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).
Yoked Contingency Management	Truvada	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).

Primary Outcome Measures

Name	Time	Method
Medication Adherence	Daily throughout medication course	Adherence to Truvada medication (if initiated) as assessed by self-report and pill count.
Time From Exposure to Truvada Initiation	6-month follow-up	Time to initiation is defined as the number of hours between exposure to viral inoculum and initiation of the Truvada medication regimen.
Course Completion	28-days post initiation	PEP course completion is a dichotomous variable (0 = Not completed; 1 = Completed) that indicates whether the participant maintained sufficient adherence to the Truvada regimen to receive all 28 doses of the medication. Note: Missing 3 Truvada doses in a row terminated the PEP-intervention and prevented Course Completion.

Secondary Outcome Measures

Name	Time	Method
Abstinence From Stimulant Drug Use (Cocaine, Amphetamine, Methamphetamine)	Thrice-weekly for 8 weeks	Abstinence will be measured using thrice weekly urine drug screens and self-report