title: The cost-effectiveness and value of information of three influenza vaccination dosing strategies for individuals with human immunodeficiency virus.
abstract: BACKGROUND
  Influenza vaccine immunogenicity is diminished in patients living with HIV/AIDS. We evaluated the cost-effectiveness and expected value of perfect information (EVPI) of three alternative influenza vaccine dosing strategies intended to increase immunogenicity in those patients.
  
  
  METHODS
  A randomized, multi-centered, controlled, vaccine trial was conducted at 12 CIHR Canadian HIV Trials Network sites. Three dosing strategies with seasonal, inactivated trivalent, non-adjuvanted intramuscular vaccine were used in HIV infected adults: two standard doses over 28 days (Strategy A), two double doses over 28 days (Strategy B) and a single standard dose of influenza vaccine (Strategy C), administered prior to the 2008 influenza season. The comparator in our analysis was practice in the previous year, in which 82.8% of HIV/AIDS received standard-dose vaccination (Strategy D). A Markov cohort model was developed to estimate the monthly probability of Influenza-like Illness (ILI) over one influenza season. Costs and quality-adjusted life years, extrapolated to the lifetime of the hypothetical study cohorts, were estimated in calculating incremental cost-effectiveness ratios (ICER) and EVPI in conducting further research.
  
  
  RESULTS
  298 patients with median CD4 of 470 cells/µl and 76% with viral load suppression were randomized. Strategy C was the most cost-effective strategy for the overall trial population and for suppressed and unsuppressed individuals. Mean ICERs for Strategy A for unsuppressed patients could also be considered cost-effective. The level of uncertainty regarding the decision to implement strategy A versus C for unsuppressed individuals was high. The maximum acceptable cost of reducing decision uncertainty in implementing strategy A for individuals with unsuppressed pVL was $418,000--below the cost of conducting a larger-scale trial.
  
  
  CONCLUSIONS
  Our results do not support a policy to implement increased antigen dose or booster dosing strategies with seasonal, inactivated trivalent, non-adjuvanted intramuscular vaccine for individuals with HIV in Canada.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT00764998.
authors.affiliation: CIHR Canadian HIV Trials Network, Vancouver, British Columbia, Canada.
authors.forename: Bohdan
authors.initials: B
authors.lastname: Nosyk
authors.forename: Behnam
authors.initials: B
authors.lastname: Sharif
authors.forename: Huiying
authors.initials: H
authors.lastname: Sun
authors.forename: Curtis
authors.initials: C
authors.lastname: Cooper
authors.forename: Aslam H
authors.initials: AH
authors.lastname: Anis
mesh_terms: D000328:Adult; D002170:Canada; D015331:Cohort Studies; D003140:Communicable Disease Control / Q000379:methods; D003362:Cost-Benefit Analysis; D004334:Drug Administration Schedule; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000821:virology*; D006801:Humans; D017589:Immunization Programs; D007251:Influenza, Human / Q000150:complications* / Q000517:prevention & control*; D007273:Injections, Intramuscular; D008297:Male; D008390:Markov Chains; D008875:Middle Aged