Pre-exposure prophylaxis for sexually-acquired HIV risk management: a review

Abstract

James Wilton,1 Heather Senn,2 Malika Sharma,3 Darrell HS Tan4,5 1Canadian AIDS Treatment Information Exchange (CATIE), 2Department of Family and Community Medicine, University of Toronto, 3Wilson Centre for Research in Education, University Health Network, University of Toronto, 4Division of Infectious Diseases, St Michael's Hospital, 5Department of Medicine, University of Toronto, Toronto, ON, Canada Abstract: Despite significant efforts, the rate of new HIV infections worldwide remains unacceptably high, highlighting the need for new HIV prevention strategies. HIV pre-exposure prophylaxis (PrEP) is a new approach that involves the ongoing use of antiretroviral medications by HIV-negative individuals to reduce the risk of HIV infection. The use of daily tenofovir/emtricitabine as oral PrEP was found to be effective in multiple placebo-controlled clinical trials and approved by the United States Food and Drug Administration. In addition, the Centers for Disease Control and Prevention in the United States and the World Health Organization have both released guidelines recommending the offer of oral PrEP to high-risk populations. The scale-up of PrEP is underway, but several implementation questions remain unanswered. Demonstration projects and open-label extensions of placebo-controlled trials are ongoing and hope to contribute to our understanding of PrEP use and delivery outside the randomized controlled trial setting. Evidence is beginning to emerge from these open-label studies and will be critical for guiding PrEP scale-up. Outside of such studies, PrEP uptake has been slow and several client- and provider-related barriers are limiting uptake. Maximizing the public health impact of PrEP will require rollout to be combined with interventions to promote uptake, support adherence, and prevent increases in risk behavior. Additional PrEP strategies are currently under investigation in placebo-controlled clinical trials and may be available in the future. Keywords: HIV prevention, biomedical intervention, tenofovir, emtricitabine