title: H1N1pdm09 adjuvanted vaccination in HIV-infected adults: a randomized trial of two single versus two double doses.
abstract: BACKGROUND
  Since human immunodeficiency virus (HIV)-infected individuals are at increased risk of severe disease from pandemic influenza A (H1N1pdm09), vaccination was recommended as a prevention strategy. The aim of the present study was to evaluate the safety, immunogenicity and persistence of the immune response after vaccination against pandemic influenza A (H1N1pdm09) with an adjuvanted vaccine in human immunodeficiency virus (HIV)-infected adults using two single and two double doses.
  
  
  RESULTS
  Open label, randomized trial to evaluate the immune response following H1N1pdm09 vaccination in HIV-infected participants compared to HIV-negative controls (NCT01155037). HIV-infected participants were randomized to receive 2 single (3.75 µg hemagglutinin) or 2 double (7.5 µg hemagglutinin) doses of the vaccine, 21 days apart. Controls received one dose of the vaccine. The primary endpoint was seroconversion as measured by hemagglutination inhibition assay. Two hundred fifty six HIV-infected participants (129 and 127 randomized to single and double doses, respectively) and 71 HIV-negative controls were enrolled. Among HIV-infected participants, seroconversion increased from 46.7% and 51.7% after the first dose to 77.2% and 83.8% after the second dose of the vaccine using single and double doses, respectively. Participants aged >40 years showed higher seroconversion compared to younger participants. Seroconversion among HIV-infected women and those with nadir CD4<200 cells/mm(3) was significantly higher with double doses. Persistence of protective antibodies six months after vaccination was achieved by 80% and 89.9% of the HIV-infected participants who received single and double doses, respectively.
  
  
  CONCLUSIONS
  Our results support the recommendation of two double doses of adjuvanted H1N1pdm09 vaccine for HIV-infected individuals, particularly women, and those aged >40 years or with nadir CD4<200 cells/mm(3), to achieve antibody levels that are both higher and more sustained.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT01155037.
authors: Instituto de Pesquisa Clínica Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Marilia
authors: M
authors: Santini-Oliveira
authors: Luiz A B
authors: LA
authors: Camacho
authors: Thiago M L
authors: TM
authors: Souza
authors: Paula M
authors: PM
authors: Luz
authors: Mauricio T L
authors: MT
authors: Vasconcellos
authors: Carmem B W
authors: CB
authors: Giacoia-Gripp
authors: Mariza G
authors: MG
authors: Morgado
authors: Estevão P
authors: EP
authors: Nunes
authors: Alberto S
authors: AS
authors: Lemos
authors: Ana C G
authors: AC
authors: Ferreira
authors: Ronaldo I
authors: RI
authors: Moreira
authors: Valdiléa G
authors: VG
authors: Veloso
authors: Marilda M
authors: MM
authors: Siqueira
authors: Beatriz
authors: B
authors: Grinsztejn
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D004334:Drug Administration Schedule; D005260:Female; D015658:HIV Infections / Q000821:virology*; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D016896:Treatment Outcome
chemical_list: D007252:Influenza Vaccines