Led by Dr. Darrell Tan and supported by the CTN+, this document provides the most update-to-date evidence for these prevention tools
In its World AIDS Day call to action, UNAIDS describes the need for transformative solutions to improve access to HIV prevention and treatment. Now published in the Canadian Medical Association Journal, the 2025 update to the Canadian Guideline on HIV Pre- and Post-exposure Prophylaxis offers up-to-date guidance for clinicians who want to expand their use of these safe and effective tools.
Supported by the CTN+ and led by Dr. Darrell Tan, who also spearheaded the original 2017 guidelines, the 2025 update presents 31 recommendations and 10 good practice statements to support clinical decision making for HIV pre- and post-exposure prophylaxis (known as PrEP and PEP).
“We have so many great options for PrEP and PEP available in Canada,” said Dr. Tan, who co-leads the CTN+ Prevention & Treatment Think Tank. “This update is about providing the most up-to-date evidence for these tools and helping to find prevention strategies suitable for all.”
Many options, one goal
Despite significant progress in the prevention of HIV in Canada, the rate of new HIV cases has increased since 2020 with many provinces and territories struggling to progress towards Canada’s 95-95-95 targets. As each region deals with its own unique challenges, biomedical tools continue to play a central role in HIV prevention.
It’s well known in public health that more options lead to more uptake. For many years, the only PrEP option was daily oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC). While very effective and safe, the daily schedule can be burdensome for some people. In recent years, there has been an upswing in the development of new antiviral regimens, modalities, and long-acting treatment for this purpose.
“PrEP is no longer one thing, it’s many things,” Dr. Tan explained in his plenary presentation earlier this year at CAHR 2025. “There should be a PrEP option well-suited to virtually anyone who could benefit.”
In support of Canada’s HIV elimination goals, the 2025 guidelines outline the recommended regimens for different HIV risk scenarios with a rating for the strength of the recommendation and the certainty of the supporting evidence, as well as suggested regular clinical monitoring for patients on PrEP.
Pathways to PrEP
Dr. Tan also emphasizes the importance of having multiple ways that people can access PrEP, which are described in the guideline’s good practice statements.
“There is still stigma surrounding PrEP and patients and providers can be apprehensive to talk about it,” said Dr. Tan. The guideline makes it clear that people who ask for PrEP should be prescribed it. Additionally, clinicians should be actively looking for opportunities to discuss and prescribe PrEP.
“Awareness of PrEP options is key,” said Dr. Tan. “Clinicians play an important role in sharing evidence-based information and counselling patients about the safety and efficacy of these medications.”
Opportunities for HIV prevention
While post-exposure options receive somewhat less attention in the media and at conferences, HIV PEP remains an important option with evolving evidence to support its use. PEP involves taking HIV medications within 72 hours after a potential exposure in order to prevent transmission.
“We have great, very tolerable PEP regimens now,” said Dr. Tan. “These options mean that clinicians have a lot of flexibility to offer their patients, based on availability, cost, drug interactions, tolerance and other factors.”
The guideline also discusses novel implementation strategies like PEP-in-pocket, where patients are provided with a 28-day PEP prescription to be used in the event of a potential HIV exposure. These strategies can be optimized to avoid missed doses, encourage follow up, and transition to PrEP.
The future of prevention
“This idea of diversity of options is a theme across the whole 2025 update,” noted Dr. Tan. “We have lots of options for medications, implementation strategies, and ways to access these preventive tools. Now it’s time to put them to use following the best evidence.”
With long-acting PrEP options like lenacapavir on the horizon, the field continues to expand with new options and modalities. While not yet approved for use as PrEP in Canada, Dr. Tan notes that tools like lenacapavir that only require an injection every 6 months is an important step forward, especially for people who face challenges with stigma, access to care, and daily adherence.
Health Canada approval for lenacapavir PrEP is expected next year and Dr. Tan and his team recently received funding from CIHR to update the guideline to include it.
While the process of guideline development can be arduous — work for the current update began as early as 2022 — Dr. Tan notes the value and importance of including diverse perspectives, extensive community engagement, rigorous methodologies, and multiple external reviews to advance the broad uptake of these tools.
“We have made tremendous clinical progress in the field of biomedical HIV prevention and our hope is that this document can support communities in harnessing the transformative potential of PrEP and PEP,” Dr. Tan added.
Co-authors on the guideline include representatives from organizations and institutions across Canada, including CTN+ Researchers Drs. Mark Hull (Treatment & Management Co-lead), Jean-Guy Baril, Joseph Cox, Marianne Harris, Debbie Kelly, Gilles Lambert, Patrick O’Byrne, Caley Shukalek, Ameeta Singh, and Cécile Tremblay.
