title: HIV pre-exposure prophylaxis (PrEP): a review of current knowledge of oral systemic HIV PrEP in humans.
abstract: OBJECTIVE
  Despite established HIV prevention strategies and broadly available diagnostic strategies in developed western countries, rates of HIV new infections remain high. Alternative strategies for HIV prevention, particularly among men who have sex with men (MSM), are crucial. HIV pre-exposure prophylaxis (PrEP) has been discussed as one additional option that this review seeks to explore.
  
  
  METHODS
  An online search identifying PrEP-relevant literature from 1st January 2010 to 1st August, 2015 was performed.
  
  
  RESULTS
  The iPrEx study, first published in 2010, demonstrated a reduction in relative risk (RRR) of HIV seroconversion of 44 % for continuous PrEP with tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) in MSM. The efficacy of PrEP has been confirmed for continuous PrEP in the PROUD study and for intermittent PrEP in the IPERGAY study (RRR = 86 % in both studies). The PrEP was well tolerated in all studies, and the evolution of HIV resistance has been low. Compensatory increased sexual risk behavior was not observed in recent studies. In contrast to the high efficacy of risk reduction for HIV transmission in MSM, the results of TDF PrEP and TDF/FTC PrEP studies using microbicidal agents or pills among heterosexual women were different (RRR 6-75 %).
  
  
  CONCLUSIONS
  Continuous and intermittent PrEP demonstrated high efficacy in preventing HIV seroconversion, notably among MSM. PrEP was well tolerated. Adherence was critical for high efficacy in all studies. Further studies to evaluate implementation strategies and cost-effectiveness in different risk populations are needed as well as drug approval in Europe.
authors.affiliation: Department of Medicine II, University Hospital Klinikum rechts der Isar der TUM, Ismaningerstr. 22, 81675, Munich, Germany. christoph.spinner@tum.de.|German Center for Infection Research (DZIF), Brunswick, Germany. christoph.spinner@tum.de.
authors.forename: Christoph D
authors.initials: CD
authors.lastname: Spinner
authors.affiliation: Department of Internal Medicine I, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127, Bonn, Germany.|German Center for Infection Research (DZIF), Brunswick, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Boesecke
authors.affiliation: Department of Dermatology and Allergology, University Hospital Klinikum rechts der Isar der TUM, Biedersteiner Str. 29, 80802, Munich, Germany.|German Center for Infection Research (DZIF), Brunswick, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Zink
authors.affiliation: Medical Group Practice, Motzstr. 19, 10777, Berlin, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Jessen
authors.affiliation: ICH Study Center, Grindelallee 25, 20146, Hamburg, Germany.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Stellbrink
authors.affiliation: Department of Internal Medicine I, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127, Bonn, Germany.|German Center for Infection Research (DZIF), Brunswick, Germany.
authors.forename: Jürgen Kurt
authors.initials: JK
authors.lastname: Rockstroh
authors.affiliation: Department of Dermatology, University of Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany. stefan.esser@uk-essen.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Esser
mesh_terms: D000284:Administration, Oral; D044966:Anti-Retroviral Agents / Q000008:administration & dosage*; D015658:HIV Infections / Q000517:prevention & control*; D006801:Humans; D055118:Medication Adherence; D065129:Pre-Exposure Prophylaxis / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D044966:Anti-Retroviral Agents
keywords: HIV; PrEP; Pre-exposure prophylaxis; Review