By Sean Cahill
Initial results from clinical prevention trials of pre-exposure chemoprophylaxis (PrEP), in oral pill form indicate that PrEP could be the “game changer” needed to more effectively fight HIV. PrEP involves taking antiretroviral medications to prevent HIV.
PrEP has shown partial efficacy with men who have sex with men (MSM) and heterosexuals. Biomedical prevention interventions such as PrEP have great potential, especially if coupled with traditional prevention approaches, expanded testing, and linkage to treatment and care. Modeling demonstrates the most effective deployment of PrEP will be in combination with scaled-up HIV treatment of people who are known to be HIV-positive, as this was shown to reduce infections.
Guidance from the US Public Health Service and the World Health Organization is expected later this year. The Food and Drug Administration announced February 13th that it would review Gilead Science’s application to use FTC-TDF (brand name Truvada) for PrEP by June 15th. Demonstration projects to develop real world best practices for implementing PrEP are underway or set to launch soon in the United States and in sub-Saharan Africa. While the cost of PrEP in the U.S. would be substantial, private insurers and state Medicaid departments are open to providing coverage. Low-cost generic medications could enable access in low-income countries. The prioritization of highly vulnerable populations could increase the cost-effectiveness of PrEP. Providing PrEP is also much less expensive than treating someone for HIV over the course of a lifetime. Recent modeling of PrEP implementation coupled with scaled up treatment—focusing on MSM in San Francisco, the general adult population in Botswana, and serodiscordant couples in South Africa—predicts that PrEP could significantly reduce HIV incidence and prevalence.
In February 2012, The Fenway Institute released an analysis of PrEP implementation issues, titled Pre-exposure prophyalxis for HIV prevention: Moving toward implementation. This report summarizes the state of PrEP and microbicide research as of early 2012, looks at willingness to use PrEP among various populations, addresses concerns about PrEP that could present obstacles to implementation, offers strategies for effective implementation, and examines policy issues related to cost and how to make PrEP accessible to those most vulnerable to HIV. Based on a review of published research and interviews with policy makers, funders and other stakeholders, it examines regulatory developments and planning underway both within the U.S. and globally.
Fenway was a US site for the global iPrEx PrEP study with gay and bisexual men and transgender women. We are very optimistic about the potential for PrEP to revolutionize HIV prevention and allow us to dramatically reduce new infections here and around the world.
PrEP must be accompanied by sustained care and behavioral interventions to ensure adherence, minimize risk compensation (the fear that people will stop using condoms), and monitor side effects. Because the most at-risk do not access regular clinical care, alternative implementation arrangements will be necessary. National monitoring systems are critical to preventing the spread of drug-resistant HIV.
Some have raised concerns about PrEP related to potential side effects, risk compensation (the idea that people will stop using condoms if PrEP becomes available), and drug resistance. However, reviews of five major clinical trials involving about 6,000 participants by the Forum for Collaborative HIV Research shows no greater risk of side effects, no risk compensation, and no clinically significant development of drug resistance in participants.
The analysis concludes with recommendations for implementation of PrEP, including the following:
• If the FDA, which is considering approving FTC-TDF for use as PrEP, feels that research on PrEP’s efficacy among heterosexuals is inconclusive, it should consider approving PrEP for MSM now separately, and consider heterosexuals, injection drug users, and other populations when the science warrants this.
• The World Health Organization (WHO) should issue guidance on PrEP that takes into account the promising results of the iPrEx study, Partners PrEP, and the Botswana CDC study.
• States should provide access to PrEP as a critical prevention service and prescription medication under the Essential Health Benefits provision of the Affordable Care Act.
•Subsequent to FDA approval, State Medicaid programs should cover PrEP as a cost-saving measure that will improve public health and ultimately save money in health care costs.
•Global funders of HIV prevention and care should make resources available for PrEP and treatment as prevention.
Sean Cahill, is director of health policy research at The Fenway Institute and an adjunct assistant professor of public administration at New York University’s Wagner School of Public Service.