About three-quarters of infectious disease physicians in North America said they favored HIV pre-exposure prophylaxis (PrEP), but only 9% reported that they had prescribed Truvada (tenofovir/emtricitabine) for this purpose, according to a report in the December 6, 2013, advance edition of Clinical Infectious Diseases.
PrEP refers to using antiretroviral drugs to prevent HIV from establishing infection after exposure. The FDA approved Truvada for PrEP in July 2012.
The iPrEx study of gay/bisexual men and transgender women showed that once-daily Truvada PrEP reduced the risk of new HIV infections by 42% overall, and by more than 90% among participants with measurable blood drug levels. Likewise, the Partners PrEP and TDF2 trials found that daily Truvada reduced the incidence of new infections among heterosexual couples, while the Bangkok Tenofovir Study showed that PrEP using tenofovir alone reduced the risk of HIV acquisition by half among people who inject drugs. Results have not been as good, however, in studies of PrEP for women in Africa due to low adherence.
In June 2013, Maile Karris from the University of California at San Diego and colleagues conducted a survey of infectious diseases physicians' opinions and practice regarding PrEP through the Emerging Infections Network (EIN), a CDC-funded sentinel network of more than 1000 infectious disease specialists, mostly in North America.
Results
o HIV negative people with HIV positive partners who were not on antiretroviral therapy (89%);
o Gay/bisexual men having unprotected sex (79%);
o Gay/bisexual men with multiple sex partners (74%);
o Heterosexuals having unprotected sex (61%);
o Heterosexuals with multiple sex partners (59%).
"The majority of adult infectious disease physicians across the U.S. and Canada support PrEP but have vast differences of opinion and practice, despite the existence of CDC guidance," the study authors concluded.
"[A] wide range of PrEP practices existed among those who have or would give PrEP, including differences in deciding who is eligible for PrEP, how persons on PrEP are followed-up, and how PrEP is discontinued," they elaborated in their discussion. "Barriers to the provision of PrEP were many with concerns about PrEP efficacy in the real-world being the greatest concern...[D]espite CDC guidance documents, great variability exists in the real-world practice of PrEP suggesting either unawareness of, disagreement with, or ambiguity in CDC guidance."
The survey appears to reflect lack of knowledge about some aspects of PrEP, as studies have largely allayed concerns about drug resistance, side effects (at least in the short-term), and risk compensation, or reduction of other safer-sex practices such as condom use.
This survey, focused on infectious disease specialists, did not include general practitioners, physicians with other specialties, or mid-level providers such as nurse practitioners who may be called on to provide PrEP in real-world practice.
"The success of real-world PrEP will likely require multifaceted programs addressing barriers to its provision and will be assisted with the development of comprehensive guidelines for real-world PrEP," the authors recommended. "The results of this survey and the additional comments provided by participants have highlighted the importance of future studies that specifically address the efficacy and risk compensation that occurs in open-label PrEP, the development of point-of-care objective adherence measures, description of long-term consequences of PrEP in HIV negative persons, the design of successful and 'resource-light' approaches to risk reduction and adherence counseling, and novel approaches to improving PrEP cost-effectiveness."
1/10/14
Reference
MY Karris, SE Beekman, S Mehta, et al. Are We Prepped for PrEP? Provider Opinions on the Real-World Use of PrEP in the U.S. and Canada. Clinical Infectious Diseases. December 6, 2013 (Epub ahead of print).