title: An Ad5-vectored HIV-1 vaccine elicits cell-mediated immunity but does not affect disease progression in HIV-1-infected male subjects: results from a randomized placebo-controlled trial (the Step study).
abstract: BACKGROUND
  The Step study was a randomized trial to determine whether an adenovirus type 5 (Ad5) vector vaccine, which elicits T cell immunity, can lead to control of human immunodeficiency virus (HIV) replication in participants who became HIV-infected after vaccination.
  
  
  METHODS
  We evaluated the effect of the vaccine on trends in HIV viral load, CD4+ T cell counts, time to initiation of antiretroviral therapy (ART), and AIDS-free survival in 87 male participants who became infected with HIV during the Step study and who had a median of 24 months of post-infection follow-up.
  
  
  RESULTS
  There was no overall effect of vaccine on mean log(10) viral load (estimated difference between groups, -0.11; P = .47). In a subset of subjects with protective HLA types (B27, B57, B58), mean HIV-1 RNA level over time was lower among vaccine recipients. There was no significant difference in CD4+ T cell counts, time to ART initiation, or in AIDS-free survival between HIV-1-infected subjects who received vaccine versus those who received placebo.
  
  
  CONCLUSIONS
  HIV RNA levels, CD4+ T cell counts, time to initiation of ART, and AIDS-free survival were similar in vaccine and placebo recipients. There may have been a favorable effect of vaccine on HIV-1 RNA levels in participants with HLA types associated with better control of HIV-1.
authors.affiliation: Center for Global Health, Weill Cornell Medical College, New York, New York 10021, USA. dfitzgerald@gheskio.org
authors.forename: D W
authors.initials: DW
authors.lastname: Fitzgerald
authors.forename: H
authors.initials: H
authors.lastname: Janes
authors.forename: M
authors.initials: M
authors.lastname: Robertson
authors.forename: R
authors.initials: R
authors.lastname: Coombs
authors.forename: I
authors.initials: I
authors.lastname: Frank
authors.forename: P
authors.initials: P
authors.lastname: Gilbert
authors.forename: M
authors.initials: M
authors.lastname: Loufty
authors.forename: D
authors.initials: D
authors.lastname: Mehrotra
authors.forename: A
authors.initials: A
authors.lastname: Duerr
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology*; D000260:Adenoviruses, Human / Q000235:genetics / Q000276:immunology; D000328:Adult; D044966:Anti-Retroviral Agents / Q000627:therapeutic use; D015153:Blotting, Western; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002944:Circumcision, Male; D018572:Disease-Free Survival; D004311:Double-Blind Method; D005822:Genetic Vectors; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology / Q000517:prevention & control*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D006801:Humans; D007111:Immunity, Cellular; D008297:Male; D008875:Middle Aged; D010919:Placebos; D016016:Proportional Hazards Models; D012367:RNA, Viral / Q000097:blood / Q000276:immunology; D019562:Viral Load / Q000187:drug effects; D055815:Young Adult
chemical_list: D016915:AIDS Vaccines; D044966:Anti-Retroviral Agents; D010919:Placebos; D012367:RNA, Viral