In January 2018, a province-wide HIV pre-exposure prophylaxis (PrEP) program was launched in British Columbia (BC), Canada, to complement the existing publicly-funded HIV treatment as prevention strategy. BC residents were eligible to receive publicly-funded emtricitabine-tenofovir DF through the centralized BC Centre for Excellence in HIV/AIDS program if they were at risk of HIV acquisition according to BC PrEP Guidelines. We sought to evaluate program retention and the rate of new HIV diagnoses.
Individuals enrolled in the BC PrEP program between 1-Jan-2018 and 30-Jun-2019 were characterized by clinical, demographic, and prescriber characteristics. For those who initiated PrEP, we determined program status at end of follow-up (31-Aug-2019). Multivariate logistic regression was used to evaluate factors associated with program non-retention (defined as >6 month lapse beyond expected PrEP refill date). Rate of new HIV diagnoses in the cohort was calculated.
In the first 18 months, 4648 individuals applied for PrEP and 4570 enrolled in the program [98% male, median age 33 years (Q1-Q3, 27-44)]. Most participants (90%) qualified based on an HIV Incidence Risk Index (HIRI) for MSM Score of ≥10 [median 19 (Q1-Q3, 15-25)]. The majority of participants (83%) resided in Greater Vancouver and received care at sexual health clinics (47%), HIV-focused clinics (23%) or general practice/other settings (30%). Of the 4451 participants who initiated PrEP, 84% were retained in the program as of 31-Aug-2019 (See Figure 1). Factors associated with program non-retention were higher HIRI-MSM score [adjusted OR 1.29 (95% CI, 1.12-1.48) per 10 score increment] and prescriber-reported on-demand PrEP use [adjusted OR 4.09 (95% CI, 3.01-5.55)] but not age, urban vs. rural location, or provider antiretroviral treatment or PrEP prescribing experience. Among participants who initiated PrEP, there were 8 HIV seroconversions in 4141 person years of follow-up, including 6 persons with >30 day lapse in PrEP medication prior to HIV diagnosis. Overall, new HIV diagnosis rate was 0.19 per 100 person years (95% CI, 0.08-0.38).
In the context of a publicly funded, centrally distributed PrEP program, retention was high at 18 months, and the rate of new HIV diagnoses low relative to the expected rate for individuals reporting these risk behaviours. Persons with higher HIRI-MSM score were at increased risk of program non-retention, and thus may benefit from enhanced support.