for males ages 18 years and up (full criteria)
Healthy Volunteers
healthy people welcome
at San Francisco, California and other locations
study started
estimated completion
Principal Investigator
by Mallory Johnson, PhD



This multi-site randomized controlled trial enrolling sexual minority men who use stimulants and are currently taking pre-exposure prophylaxis (PrEP). This randomized controlled trial will test the efficacy of a PrEP Affect Regulation Treatment Innovation (PARTI) condition comprised of a 5-session positive affect intervention delivered during smartphone-based Contingency Management (CM) for directly observed PrEP doses (PARTI+CM) compared to an attention-control condition delivered during CM. The primary outcome is HIV acquisition risk measured using a combination of tenofovir-diphosphate levels in dried blood spots that are indicative of sub-optimal adherence to PrEP and recent condomless anal sex.

Official Title

Optimizing PrEP Adherence in Sexual Minority Men Who Use Stimulants


Medication Adherence, HIV Prevention, Stimulant Use, Sexual Minority Men, HIV, PrEP Adherence, Contingency Management, PARTI, Contingency Management for PrEP Adherence, PARTI and CM (Contingency Management)


You can join if…

Open to males ages 18 years and up

  • Assigned male at birth
  • Identifies as male and/or a gender minority
  • Age 18 or older
  • Reads and speaks English
  • Past 6 months, reports condomless anal sex (CAS) with men
  • HIV negative
  • Currently has an active prescription for daily oral PrEP for at least 2 months and reports any non-adherence in the past month OR was initiated on PrEP in the past 2 months, regardless of reported adherence
  • Has an iPhone or Android smartphone
  • Screens positive for a moderate or severe stimulant use disorder with an abbreviated version of the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST) (total score of 4 or more) OR reports weekly use of either methamphetamine and/or cocaine.
  • Lives in California or Florida

You CAN'T join if...

  • Unable to provide informed consent
  • Unwilling to participate in smartphone-based CM for directly observed PrEP doses
  • Assigned female at birth
  • Unwilling to provide dried blood spot (DBS) specimen - either in-person or remotely
  • Plans to move out of the state in the next 6 months
  • Not taking PrEP daily (e.g., if taking intermittent 2-1-1 dosing)
  • Switched from Truvada to Descovy in the last 5 months


  • University of California, San Francisco accepting new patients
    San Francisco California 94143 United States
  • University of Miami accepting new patients
    Miami Florida 33136 United States

Lead Scientist at UCSF


accepting new patients
Start Date
Completion Date
University of Miami
Study Type
Expecting 350 study participants
Last Updated