Optimizing the delivery of HIV post-exposure prophylaxis: A randomized controlled trial of text messaging support and physician to nurse task-shifting (OPT-IN)

In Progress

Access to Medications

HIV/Sexually Transmitted and Blood-borne Infections

Non-occupational post-exposure prophylaxis (nPEP) is an antiretroviral drug treatment strategy that can prevent HIV infection, if taken shortly after an exposure to HIV and continued for 28 days.

Although nPEP is widely accepted as an appropriate option for preventing HIV, new infections still occur in Canada at unacceptable rates. Two key implementation challenges have limited nPEP’s clinical and public-health impact in Canada: not all patients complete their 28-day course of medication and get the follow-up care they need, and many rely on specialized, infectious-disease physicians for nPEP prescriptions and care.

Developing and testing new and better ways to deliver this underutilized, effective intervention.

We are evaluating two new models of nPEP delivery, each of which could dramatically change how health systems – in Canada and beyond – roll out this intervention.

  1. Text-message support. This could help prompt more nPEP patients to complete their course of medication and follow-up blood work, and to attend follow-up appointments
  2. Nurse-led nPEP follow-up. This could make it possible to shift nPEP delivery to sexual-health clinics and nurses – more accessible options for patients.

Study results will provide important information on how to strengthen retention in care, reduce costs to the health-care system for nPEP delivery province-wide, and optimize the scope of practice of nurses and physicians.

About this study

This is a pragmatic, multicenter, randomized controlled trial using a 2×2 factorial design to determine whether the proportion of nPEP patients that successfully complete their 28-day nPEP regimen and follow-up:

  1. Is higher among those receiving mobile phone-based text messaging support than among those receiving standard care
  2. Is non-inferior among those receiving care from a sexual health clinic nurse compared to those receiving hospital-based physician care.

The study will also generate important findings about the tolerability and adherence associated with a novel nPEP regimen, bictegravir / tenofovir alafenamide / emtricitabine (Biktarvy®).

Access to Medications

HIV/Sexually Transmitted and Blood-borne Infections

Dr. Darrell Tan

An infectious diseases physician and Canada Research Chair in HIV Prevention and STI Research, Dr. Darrell Tan is dedicated to improving the prevention, detection and management of HIV and sexually transmitted co-infections such as herpes and syphilis.


  • Dr. Isaac Bogoch (Toronto General Hospital) Principal Investigator
  • Dr. Arlene Chan (Women’s College Hospital)
  • Dr. Allison Chris (Toronto Public Health)
  • Mr. Ken English (Ontario AIDS Bureau)
  • Dr. Rich Lester (University of British Columbia)
  • Mr. John Maxwell (AIDS Committee of Toronto)
  • Dr. Rita Shahin (Toronto Public Health)
  • Dr. Hubert Wong (CIHR Canadian HIV Trials Network)


  • Canadian Institutes of Health Research
  • Gilead Sciences, Inc.


  • Crossways Sexual Health Clinic
  • Toronto Public Health
  • AIDS Committee of Toronto

Contact Info

Attia Qamar

Study Project Manager

(416) 360-4000 ext. 77325