Back Back
HIV Prevention in Canada
Strategies for HIV Prevention in Canada: HIVR4P 2024

Released: November 04, 2024

Expiration: November 03, 2025

Mark Hull
Mark Hull, MD, MHSC, FRCPC
Activity Information

Activity

Progress
1
Course Completed
Key Takeaways
  • HIV infections are on the rise in Canada, necessitating implementation of innovative HIV prevention strategies, including expansion of PrEP in diverse populations and novel PrEP modalities.

HIV remains an ongoing public health concern in Canada. New HIV diagnoses have risen nationally, with a 24.9% increase in cases from 2021 to 2022. National data highlight ongoing marked disparities in case distribution across the country, with an explosive rise in new diagnoses in the Prairie provinces, with rates of 13.9 and 19.0 cases/100,000 people for Manitoba and Saskatchewan compared with 4.7/100,000 people for the country as a whole.

In these settings, the epidemic is driven predominantly by transmission through heterosexual contact and injection drug use, compared with transmission in gay, bisexual, and other men who have sex with men, who constitute a priority population in other regions. This trend was witnessed in Alberta, with heterosexual transmission becoming the predominant cause of locally acquired infection in 2023. British Columbia, which has seen a steady decrease in new diagnoses over the last decade, has also reported an upswing in cases for 2024.

Overall, this trend in rising new diagnoses challenges our progress toward meeting UNAIDS 90-90-90 targets and highlights the importance of enhanced and creative HIV prevention strategies, including the expansion of HIV pre-exposure prophylaxis (PrEP) in diverse populations across Canada.

Data presented at the recent International AIDS Society HIV Prevention Conference (HIVR4P Lima, Peru, October 6-10, 2024) provided clear guidance to meet this need.

Key Highlights for HIV Prevention in Canada

 PrEP Knowledge Among Existing Users
Oral PrEP has been widely available in Canada since 2018. A cross-sectional survey of current PrEP users following an educational campaign with a focus on risk minimization measures found that among 69 current PrEP users, 75.4% demonstrated adequate knowledge regarding PrEP use and monitoring. The majority had been using PrEP for >1 year, were predominantly male, and demonstrated high levels of adherence to regular HIV testing (88% had undergone testing in the prior 3 months).

Respondents highlighted the key role of healthcare professionals (HCPs) for PrEP knowledge diffusion (69.6% noted HCPs as their main source of PrEP knowledge) and supported evidence of a trend to condomless sex while using PrEP (66.6% indicated they were less likely to use condoms while on PrEP). These findings highlight the need for effective PrEP communication strategies by HCPs, regular sexually transmitted infection (STI) testing, and other STI prevention strategies.

Promise of Novel PrEP Modalities to Draw New Populations Into Care
The advent of novel PrEP therapies, notably injectable agents, offers more choices for individuals where daily therapy is compromised by barriers to regular access, stigma, or adherence concerns. Data presented at HIVR4P demonstrated the promise of such agents.

Real-world experience through which the San Francisco Department of Public Health provided long-acting cabotegravir (LA CAB) to vulnerable individuals in urban populations at primary care clinics was described. These clinics provide care to marginalized individuals, with the majority reporting an underlying mental health diagnosis, substance use, or unstable housing. Outcomes demonstrated LA CAB success: 85% of individuals received on-time injections, and 83% (95% CI: 75%-91%) remained on PrEP at 6 months, a far higher proportion than historical experience with oral PrEP in the network had shown (approximately 60%). Very few individuals discontinued due to adverse events (3.6%), and no seroconversions were noted.

A key feature of this study was the proportion of individuals receiving LA CAB who experienced failure with prior oral PrEP or were PrEP naive (33.3% and 27.9%, respectively). To me, one of most exciting aspects of novel PrEP strategies is drawing in these new populations.

This feature was also reported in a real-world demonstration project of LA CAB implementation in a high-prevalence setting in Zambia: 70% of participants enrolled were naive to oral PrEP.

These studies have immediate applicability to a Canadian context both in inner city populations such as Vancouver’s downtown Eastside neighborhood (with a high prevalence of substance users at risk for HIV), and rural contexts in Saskatchewan and Manitoba (where PrEP access has been limited).

New Agents and Strategies to Simplify HIV Prevention Delivery
The realm of injectable PrEP was expanded at HIVR4P with  PURPOSE-2, a phase III trial of subcutaneous twice-yearly lenacapavir in gay and bisexual men and transgender women. The findings build on published data from the PURPOSE-1 trial and demonstrated a significant reduction in HIV incidence. To me, lenacapavir offers great promise for HIV prevention in Canada’s high-incidence regions, particularly because its twice-yearly nature may be easily adapted to rural settings and already overburdened healthcare systems.

Acceptability of a simplified PrEP delivery package was also assessed in an ongoing qualitative study in Kenya. Interim results from the comparison of 6 months of PrEP dispensing with interim HIV self-testing vs quarterly standard of care visits showed that the decreased frequency of visits/longer prescription length was highly acceptable and less burdensome than standard of care. However, concerns regarding limited access to counselling opportunities and accuracy of test results were noted. This approach should be evaluated in a Canadian context to decrease PrEP wait times and increase healthcare utilization of PrEP users.

Similarly, an updated report examined simplified access to postexposure prophylaxis (PEP) (ie, PEP-in-pocket [PIP], where individuals generally at low HIV risk were given a prestanding prescription for PEP to be used in case of unexpected exposure. The results demonstrated the acceptability of this strategy. In 2 HIV prevention clinics in Toronto, PIP was prescribed to 126 individuals who were followed for 212 patient-years.

Although baseline screening was attended only 30.3% of the time, 6-month follow-up attendance following PIP initiation was 98.7%. Zero HIV seroconversions were noted, 31.7% of patients switched from PIP to PrEP, and 29.4% switched from PrEP to PIP. This approach may add to individual-level choice, but a formal comparison with an on-demand PrEP strategy is needed to determine its true value.

Conclusions
Rates of new HIV diagnoses appear to be on the rise in Canada. Healthcare systems in close collaboration with community partners must embrace new approaches to HIV prevention and work swiftly to decrease system-level barriers to access to testing, counselling, and biomedical PrEP services. Data from the HIVR4P conference can be used to drive new strategies for HIV prevention.

Your Thoughts?
What novel PrEP option excites you most? Get involved in the discussion by posting a comment below.