title: Preexposure chemoprophylaxis for HIV prevention in men who have sex with men.
abstract: BACKGROUND
  Antiretroviral chemoprophylaxis before exposure is a promising approach for the prevention of human immunodeficiency virus (HIV) acquisition.
  
  
  METHODS
  We randomly assigned 2499 HIV-seronegative men or transgender women who have sex with men to receive a combination of two oral antiretroviral drugs, emtricitabine and tenofovir disoproxil fumarate (FTC-TDF), or placebo once daily. All subjects received HIV testing, risk-reduction counseling, condoms, and management of sexually transmitted infections.
  
  
  RESULTS
  The study subjects were followed for 3324 person-years (median, 1.2 years; maximum, 2.8 years). Of these subjects, 10 were found to have been infected with HIV at enrollment, and 100 became infected during follow-up (36 in the FTC-TDF group and 64 in the placebo group), indicating a 44% reduction in the incidence of HIV (95% confidence interval, 15 to 63; P=0.005). In the FTC-TDF group, the study drug was detected in 22 of 43 of seronegative subjects (51%) and in 3 of 34 HIV-infected subjects (9%) (P<0.001). Nausea was reported more frequently during the first 4 weeks in the FTC-TDF group than in the placebo group (P<0.001). The two groups had similar rates of serious adverse events (P=0.57).
  
  
  CONCLUSIONS
  Oral FTC-TDF provided protection against the acquisition of HIV infection among the subjects. Detectable blood levels strongly correlated with the prophylactic effect. (Funded by the National Institutes of Health and the Bill and Melinda Gates Foundation; ClinicalTrials.gov number, NCT00458393.).
authors.affiliation: J. David Gladstone Institutes, University of California at San Francisco, 1650 Owens St., San Francisco, CA 94158, USA. robert.grant@ucsf.edu
authors.forename: Robert M
authors.initials: RM
authors.lastname: Grant
authors.forename: Javier R
authors.initials: JR
authors.lastname: Lama
authors.forename: Peter L
authors.initials: PL
authors.lastname: Anderson
authors.forename: Vanessa
authors.initials: V
authors.lastname: McMahan
authors.forename: Albert Y
authors.initials: AY
authors.lastname: Liu
authors.forename: Lorena
authors.initials: L
authors.lastname: Vargas
authors.forename: Pedro
authors.initials: P
authors.lastname: Goicochea
authors.forename: Martín
authors.initials: M
authors.lastname: Casapía
authors.forename: Juan Vicente
authors.initials: JV
authors.lastname: Guanira-Carranza
authors.forename: Maria E
authors.initials: ME
authors.lastname: Ramirez-Cardich
authors.forename: Orlando
authors.initials: O
authors.lastname: Montoya-Herrera
authors.forename: Telmo
authors.initials: T
authors.lastname: Fernández
authors.forename: Valdilea G
authors.initials: VG
authors.lastname: Veloso
authors.forename: Susan P
authors.initials: SP
authors.lastname: Buchbinder
authors.forename: Suwat
authors.initials: S
authors.lastname: Chariyalertsak
authors.forename: Mauro
authors.initials: M
authors.lastname: Schechter
authors.forename: Linda-Gail
authors.initials: LG
authors.lastname: Bekker
authors.forename: Kenneth H
authors.initials: KH
authors.lastname: Mayer
authors.forename: Esper Georges
authors.initials: EG
authors.lastname: Kallás
authors.forename: K Rivet
authors.initials: KR
authors.lastname: Amico
authors.forename: Kathleen
authors.initials: K
authors.lastname: Mulligan
authors.forename: Lane R
authors.initials: LR
authors.lastname: Bushman
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Hance
authors.forename: Carmela
authors.initials: C
authors.lastname: Ganoza
authors.forename: Patricia
authors.initials: P
authors.lastname: Defechereux
authors.forename: Brian
authors.initials: B
authors.lastname: Postle
authors.forename: Furong
authors.initials: F
authors.lastname: Wang
authors.forename: J Jeff
authors.initials: JJ
authors.lastname: McConnell
authors.forename: Jia-Hua
authors.initials: JH
authors.lastname: Zheng
authors.forename: Jeanny
authors.initials: J
authors.lastname: Lee
authors.forename: James F
authors.initials: JF
authors.lastname: Rooney
authors.forename: Howard S
authors.initials: HS
authors.lastname: Jaffe
authors.forename: Ana I
authors.initials: AI
authors.lastname: Martinez
authors.forename: David N
authors.initials: DN
authors.lastname: Burns
authors.forename: David V
authors.initials: DV
authors.lastname: Glidden
mesh_terms: D000225:Adenine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use; D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D019380:Anti-HIV Agents / Q000009:adverse effects / Q000097:blood / Q000627:therapeutic use*; D003841:Deoxycytidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use; D024882:Drug Resistance, Viral; D004359:Drug Therapy, Combination; D000068679:Emtricitabine; D005500:Follow-Up Studies; D006678:HIV / Q000235:genetics / Q000302:isolation & purification; D015483:HIV Antibodies / Q000097:blood; D015658:HIV Infections / Q000175:diagnosis / Q000453:epidemiology / Q000517:prevention & control*; D006679:HIV Seropositivity / Q000175:diagnosis; D018451:Homosexuality, Male; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009325:Nausea / Q000139:chemically induced; D063065:Organophosphonates / Q000009:adverse effects / Q000097:blood / Q000627:therapeutic use*; D010349:Patient Compliance; D012367:RNA, Viral / Q000097:blood; D000068698:Tenofovir; D014189:Transsexualism; D055815:Young Adult
chemical_list: D019380:Anti-HIV Agents; D015483:HIV Antibodies; D063065:Organophosphonates; D012367:RNA, Viral; D003841:Deoxycytidine; D000068698:Tenofovir; D000068679:Emtricitabine; D000225:Adenine