for males ages 18 years and up (full criteria)
Healthy Volunteers
healthy people welcome
at San Diego, California
study started
completion around
Principal Investigator
by Susan J Little, MD
Headshot of Susan J Little
Susan J Little



The long-term goal of this research is to develop a theoretically grounded, effective, accessible and sustainable mHealth PrEP care continuum intervention for racially/ethnically diverse transgender women (TW) and gay, bisexual, and other men who have sex with men (GBMSM) disproportionately impacted by the HIV epidemic.

To reach this goal, the investigators will compare study outcomes among persons randomized to use a mobile app (eSTEP) intervention tailored to the unique needs of TW and GBMSM with interactive components delivered before in-person HIV testing and PrEP initiation visit and interactive components delivered after PrEP is initiated. The eSTEP group will be compared to usual HIV testing and PrEP care.


Study Design:

The investigators propose to evaluate the feasibility, acceptability, and preliminary impact of eSTEP in a pilot RCT with transgender women (TW) and gay, bisexual, and other men who have sex with men (GBMSM) who are either PrEP naïve or have not been taking PrEP for at least 3 months, randomized (2:1) to receive either the eSTEP intervention or usual PrEP prevention services, and followed for 6 months with assessments at baseline, 12- and 24-weeks. eSTEP is a mobile application (i.e., app) with interactive PrEP components delivered before in-person HIV testing (at a university-based HIV treatment and prevention clinic) to increase PrEP uptake, and components to optimize PrEP adherence and persistence delivered after the participant tests negative for HIV and agrees to start PrEP. eSTEP will be tailored to the unique needs of TW and GBMSM to optimize its impact and relevance for each group.

eSTEP is grounded in the Information, Motivation, Behavioral Skills model [IMB] and also draws from a model of technology adoption. eSTEP intervention components are:

  • HIV Testing and PrEP Information
  • Identify and Addressing Barriers to PrEP Uptake and Stigma
  • PrEP Eligibility Survey and Preparing to Start PrEP
  • HIV Testing Visit Preparation
  • Appointment Scheduling
  • PrEP Adherence Reminders & Self-monitoring for those who start PrEP
  • Adherence Feedback
  • PrEP Appointment Reminders
  • PrEP and Risk Reduction Information Control arm participants will not be offered the eSTEP mobile app and will receive information about how to schedule their HIV testing appointment at the HIV treatment and prevention clinic on their own (which is the standard procedure for the clinic). Community resources will be also provided electronically to control and treatment arm participants.

Study Sample:

Recruitment will be 120 adult (18 years and older) GBMSM and TW participants (n = 85 GBMSM; n = 35 TW) and will reflect at least 50% Black and/or Latinx participants to ensure that eSTEP is piloted among persons most at risk for HIV. This will allow the investigators to explore differences (e.g. by geder, race and ethnicity) for eSTEP to inform future trials.

Recruitment and Clinical Sites:

Participants will be recruited from a university-based HIV treatment and prevention clinic, as well as in the local San Diego GBMSM and TW communities through the following ways: a) ads on social media sites (e.g., Facebook/Instagram; Grindr) that will link to an online pre-screening survey, b) in-person while attending an HIV testing appointment at the HIV treatment and prevention clinic, c) community recruitment with our existing GBMSM and TW Community Advisory Boards (CABs) and partner community organizations, d) via a part-time recruiter (a peer recruiter or someone with experience in the community).

Enrollment, Randomization and Follow-up Visits:

Study candidates will complete a short online pre-screening survey to assess eligibility on REDCap. Preliminarily eligible participants will complete the enrollment visit over Zoom to verify eligibility and complete online written consent. After informed consent, participants will complete an online 30- to 45-minute baseline survey. All participants will be provided with community resources electronically by the study coordinator and asked to schedule an in-person clinical appointment at the HIV treatment and prevention clinic for routine HIV testing, eligibility and safety lab screening for PrEP as routinely offered in the HIV treatment and prevention clinic. Any participant that receives a positive test for HIV during the trial will receive appropriate post-test counseling and treatment by the HIV treatment and prevention clinic staff. All participants will also be provided 3-4 dried blood spot (DBS) testing kits to self-collect their DBS specimen for the TFV-DP analysis (PrEP adherence) with a detailed instruction sheet and link to a video demonstration of the DBS collect procedure. These kits and the first DBS collection may take place either in person at the HIV treatment and prevention clinic or if necessary, by mail.

Participants will be randomized 2:1 either to the intervention arm (eSTEP and usual care) or to the control arm (HIV testing usual care) using the randomization feature in REDCap. Participants randomized to the treatment arm (eSTEP and usual care) will be guided through setting up their user account and user profile, provided with basic training on how to navigate and use intervention components, and given the opportunity to ask questions. Participants in the treatment arm will have immediate access to eSTEP as part of the initial visit.

Participants will undergo an online 30-45-minute survey at week 12 and week 24. All participants receiving either daily oral or on-demand (2-1-1) PrEP will be asked to complete and submit a DBS specimen at week 12 and week 24 using the kits provided earlier in person at HIV treatment and prevention clinic or by mail and will be seen in-person at the HIV treatment and prevention clinic for usual PrEP care follow-up. Participant survey data will be captured in Qualtrics and, along with clinical study data collected from HIV treatment and prevention clinic HIV testing, and PrEP care appointments, will be captured in our web-based case report forms (CRFs) using REDCap (Research Electronic Data Capture) open software and securely transferred to SDSU via a deidentified file. For treatment arm participants, survey data collection may occur on a mobile device that can access the internet and will be housed on the San Diego State University server.

Study retention protocols involve the use of multiple contact methods including telephone calls, text messages, e-mail reminders, social media, and contact information for a friend/family member - and with permission for the use of each.

Exit Interviews:

10 GBMSM and 10 TW in the eSTEP intervention arm only will be purposively selected (high eSTEP user vs. low user; diversity in race/ethnicity) for a 30-60-minute exit interview to assess their experience in the intervention, suggestions for modifications to the existing interface, suggestions for new features, and changes to any study procedures.


Pre-Exposure Prophylaxis (PrEP), HIV Prevention, eSTEP


You can join if…

Open to males ages 18 years and up

  • 18 years of age or older
  • Assigned male sex at birth
  • Current male & GBMSM identity OR transfeminine (woman, transgender woman, or non-binary) identification
  • Self-reported HIV-negative status
  • English-speaking (since the pilot intervention will be developed in English)
  • Owner of an Android or iPhone mobile device and access to this phone during the 6-month study.
  • Willingness and ability to attend HIV prevention visits at the HIV treatment and prevention clinic.
  • Consent to allow study team access to study-relevant PHI
  • Eligible for PrEP following CDC guidelines (in the past 6 months had a sexual partner with HIV with unknown or detectable viral load, inconsistently used condoms, and/or was diagnosed with a sexually transmitted infection)
  • Has never used PrEP or has not used PrEP in the past 3 months

You CAN'T join if...

  • Was a Community Advisory Board Member or participant in the eSTEP focus groups
  • Assigned female or intersex at birth
  • Living with HIV
  • Already taking PrEP
  • Under 18 years old
  • Does not own a mobile phone
  • Does not speak or read English (since the pilot intervention will be developed in English)


  • San Diego State University - Department of Psychology accepting new patients
    San Diego California 92120 United States

Lead Scientist at UCSD

  • Susan J Little, MD
    Professor In Residence, Medicine, Vc-health Sciences-schools. Authored (or co-authored) 245 research publications


accepting new patients
Start Date
Completion Date
San Diego State University
Centers for Disease Control and Prevention, Preexposure prophylaxis for the prevention of HIV infection in the United States - 2021 update clinical practice guideline. 2021.
Study Type
Expecting 120 study participants
Last Updated