PrEP Intervention for People Who Inject Substances and Use Methamphetamine (PRIME)

  • End date
    May 27, 2024
  • participants needed
  • sponsor
    San Francisco Department of Public Health
Updated on 27 May 2022
HIV Vaccine
Accepts healthy volunteers


In this study, "PrEP Intervention for people who Inject Substances and Use Methamphetamine" (PRIME), we propose to assess if using video directly observed therapy with real-time contingency management (VDOT-CM) may help people assigned male sex at birth who have sex with men (MSM) who inject methamphetamine adhere to PrEP. We will randomize 140 adults who inject substances and use methamphetamine, are HIV-negative, and have recently engaged in a sexual HIV risk behavior to VDOT-CM or counseling alone for 24 weeks.

The study aims are to (1) determine the efficacy of VDOT-CM compared to counseling alone for PrEP adherence, (2) evaluate the acceptability of PrEP and adherence support strategies among the cohort, and (3) compare injection and sexual HIV risk behavior before and during PrEP use.

We hypothesize that participants randomized to VDOT-CM will have superior adherence to PrEP. We also hypothesize that participants will describe barriers to and facilitators of PrEP adherence, and those who are randomized to VDOT-CM will consider it an acceptable PrEP adherence support strategy. Finally, we do not expect to find increased injection or sexual risk behaviors for HIV among study participants after they begin taking PrEP.


New HIV infections among people who inject drugs (PWID) are increasing in the United States and San Francisco. Methamphetamine is a driving force in the transmission of HIV. Multiple studies across diverse populations have found methamphetamine use to be independently associated with both injection and sexual risk behaviors for HIV acquisition. Men who have sex with men (MSM) who inject methamphetamine are at particularly elevated risk for HIV from both injection and sexual risk behaviors.

Daily, oral pre-exposure prophylaxis (PrEP) is safe and highly effective for HIV prevention when taken consistently. The Centers for Disease Control and other health agencies recommend PrEP for PWID. Despite this recommendation and increasing PrEP use in the US, almost no PrEP studies or demonstration projects have focused on PWID. The small number of studies that have evaluated PrEP use among MSM who inject methamphetamine have shown slow PrEP uptake and adherence challenges.

The PRIME study will randomize 140 MSM who inject substances and use methamphetamine, are HIV-negative, and have recently engaged in an HIV sexual risk behavior to video directly observed therapy with contingency management (VDOT-CM) and counseling or counseling alone for 24 weeks. The primary aim of this study is to evaluate if VDOT-CM helps MSM who inject substances and use methamphetamine adhere to daily PrEP for HIV prevention. Participants will be MSM, age 18 years or older, who have injected substances and used methamphetamine within the past 30 days, are HIV negative and interested in initiating PrEP, and report condomless sero-unknown/discordant sex with a man in the past 12 months.

All subjects will complete the following study visits: screening, enrollment, follow-up visits 6, 12, and 18 weeks from enrollment, and a final follow-up visit at 24 weeks. At screening, enrollment, and all follow-up visits, laboratory testing for HIV, gonorrhea, chlamydia, and methamphetamine metabolites will be done. Syphilis and creatinine testing will be done at screening, week 12, and week 24. Syphilis testing will also be done at enrollment. In addition, hepatitis B surface antibody (HBsAb) and antigen (HBsAg) and hepatitis C antibody (HCV) testing will be done at the screening visit. HCV testing will also be done at the week 24 visit.

At screening a medical history and physical exam will be performed; during enrollment and follow-up a symptom-directed exam will be performed at all visits, and under clinician discretion, a medical history and full exam will be done if needed. AEs will be assessed starting at enrollment and throughout follow-up. Vital signs and weight will be checked at all visits.

At enrollment, participants will be randomized 1:1 to receiving only Integrated Next Step Counseling (iNSC) or iNSC and video directly-observed therapy (VDOT) with contingency management (CM). All participants will receive iNSC throughout their participation to support PrEP adherence and help their reduce risk for HIV. Dried blood spots (DBS) will be collected for FTC/TAF drug level testing at weeks 6, 12, 18, and 24. Participants randomized to the VDOT-CM arm will be asked to record taking their daily PrEP dose on VDOT every day from enrollment through week 24.

In-depth interviews will be conducted with at least 36 participants (18/arm) and participants who discontinue PrEP early or become infected with HIV during the study.

Condition HIV Infections
Treatment Video directly observed therapy with contingency management, Integrated Next-Step Counseling
Clinical Study IdentifierNCT04523519
SponsorSan Francisco Department of Public Health
Last Modified on27 May 2022


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