ViewpointPre-exposure prophylaxis for HIV infection: what if it works?
Section snippets
Pre-exposure prophylaxis
Disease prevention by prophylactic drugs is standard practice in travellers to malaria-endemic countries and for other infections such as Pneumocystis jirovecii in HIV infection. Various studies11, 12, 13, 14 show that antiretroviral treatment given at or shortly after an exposure can substantially reduce HIV transmission: prompt treatment clearly increases effectiveness.15 This observation led to the hypothesis that transmission could be decreased further if treatment was delivered before
Drug toxicity and viral resistance
Tenofovir (and tenofovir and emtricitabine) has a good safety profile and infrequent side-effects; the most common side-effects are gastrointestinal discomfort, dizziness, headache, and rash. Less than 1% of patients with HIV taking tenofovir in clinical trials had serious drug-related adverse events such as acute renal failure, Fanconi's syndrome resulting in severe hypophosphataemia, decreases in bone-mineral density, and rarely, lactic acidosis.22 Tenofovir plus emtricitabine has the same
Increased risky behaviours
Mathematical modelling of HIV transmission by people taking antiretroviral drugs suggests that reduction or reversal of any benefits could result from a small increase in risky sexual behaviour.26, 27 Although pre-exposure prophylaxis might greatly reduce HIV transmission, this effect could diminish if people taking such prophylaxis increase their risky behaviour. Moreover, HIV prophylaxis offers no protection against other sexually transmitted infections.
Present trials should provide data for
Ethics
The possibility of pre-exposure prophylaxis for HIV raises important ethical questions such as: what are the obligations of governments and industry to provide such prophylaxis? How should resources be distributed between research, treatment, counselling, testing, primary prevention, pre-exposure prophylaxis, and post-exposure prophylaxis? Who should have priority for prophylaxis? These types of issues arise in many health-care settings; however stigma associated with HIV poses particular
Public-health issues
Mathematical models of pre-exposure prophylaxis35 and topical anti-HIV microbicides,36, 37, 38 suggest that even a partially effective product could avert many infections. The trials of pre-exposure prophylaxis will provide important safety and efficacy data for prevention of HIV transmission by injecting drug users and through sexual intercourse. However, even after these trials conclude many information gaps will remain. Perhaps most important is that not all groups at risk are included. For
Steps to take today
In August, 2006, the Global HIV Prevention Working Group, an international panel of more than 50 experts on HIV and AIDS, was convened by the Bill and Melinda Gates Foundation to discuss HIV-prevention research, and released a report about factors necessary for enabling access to new HIV-prevention technology. These factors include early commitment of resources from donors, coordination between governments and regulatory agencies, and planning of guidelines for use.39 Although the first results
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Protect or Disinhibit?
New York Times Magazine (New York)
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Impact of dosing strategies on plasma concentrations of tenofovir: Implications in HIV pre-exposure prophylaxis in China
2021, Journal of Infection and Public HealthCitation Excerpt :The CDC in the US has recommended PrEP as an effective approach to prevent HIV transmission in high-risk populations. In addition, PrEP may potentially modulate immune function, attenuate HIV disease progression, therefore, reduce morbidity and decrease transmission [8]. Despite of ideal pharmacokinetics and efficacy of tenofovir for PrEP demonstrated in several clinical trials, it remains controversial regarding its long-term safety, implications of resistance development, and the cost-effectiveness of applying this agent for the prevention of HIV infection.
Exploratory survey of Florida pharmacists' experience, knowledge, and perception of HIV pre-exposure prophylaxis
2014, Journal of the American Pharmacists AssociationCitation Excerpt :Pharmacists in our survey indicated the cost of PrEP as a barrier to patient access and uptake as a viable mode of HIV prevention, a concern echoed by other health care providers in previously published PrEP surveys.14–17 The cost of PrEP has been estimated to be as high as $1,500 per month.25 For insured patients, pharmacy benefits may cover the cost, although a prior authorization is usually required.
Sexual behaviour among users of antiretroviral pre-exposure prophylaxis
2013, The Lancet Infectious DiseasesHuman immunodeficiency virus
2022, Clinical Virology: Third EditionWillingness to take and ever use of pre-exposure prophylaxis among female sex workers in Ghana
2022, Medicine (United States)