HIV Preexposure Prophylaxis: A Review

JAMA. 2018 Mar 27;319(12):1261-1268. doi: 10.1001/jama.2018.1917.


Importance: About 40 000 Americans and 2 million people worldwide are newly infected with HIV each year. The combination antiretroviral regimen, tenofovir disoproxil fumarate (TDF)/emtricitabine, taken as a single pill once daily, has been shown to prevent HIV transmission but is used by fewer than 20% of people who could benefit in the United States.

Observations: PubMed was searched on February 15, 2018, using the search terms pre-exposure, prophylaxis, HIV, and PrEP to identify English-language articles published between 2010 and 2018. Four placebo-controlled randomized clinical trials have demonstrated that preexposure prophylaxis (PrEP) with daily dosing of TDF/emtricitabine significantly reduces HIV acquisition in men who have sex with men, high-risk heterosexuals, and injection drug users who share injection equipment. The efficacy of daily TDF/emtricitabine exceeds 90% but is highly correlated with degree of adherence. TDF/emtricitabine is safe and well-tolerated. Only 2% of people discontinue PrEP because of adverse effects. Sexually transmitted infections are common among those using PrEP. Resistance to TDF/emtricitabine when used for PrEP is rare (<0.1%) and usually occurs when PrEP is inadvertently prescribed to individuals with undiagnosed acute HIV infection who have false-negative findings on HIV antibody/antigen testing due to HIV infection acquired within 7 to 10 days of testing. Effective methods are needed to identify individuals at high risk for acquiring HIV, ensure their access to PrEP, and maximize medication adherence.

Conclusions and relevance: TDF/emtricitabine is an effective and safe therapy for preventing HIV transmission. Increasing prescription of TDF/emtricitabine for patients at risk of acquiring HIV has the potential to reduce new HIV infections.

Publication types

  • Review

MeSH terms

  • Anti-HIV Agents / adverse effects
  • Anti-HIV Agents / therapeutic use*
  • Disease Transmission, Infectious / prevention & control
  • Drug Combinations
  • Emtricitabine / adverse effects
  • Emtricitabine / therapeutic use*
  • HIV Infections / prevention & control*
  • HIV Infections / transmission
  • Humans
  • Pre-Exposure Prophylaxis*
  • Risk Factors
  • Tenofovir / adverse effects
  • Tenofovir / therapeutic use*


  • Anti-HIV Agents
  • Drug Combinations
  • Tenofovir
  • Emtricitabine