Influenza Vaccine in HIV
Condition: Influenza; HIV
MeSH terms: Influenza, Human
Study type: Interventional
Phase: Phase 3

Summary: 
      The purposes of this research study are:

        1. to see if there is a difference in the quantity of protective influenza antibodies
           produced by different doses of the Fluviral vaccine

        2. to see if these different vaccine dosing schedules reduce flu-like illness and/or reduce
           laboratory documented influenza in HIV Infected adults.
    

Detailed description: 
      Immune compromised individuals are at risk for infection with influenza and more likely to
      manifest more severe symptoms of influenza disease. Furthermore, they are influenza vaccine
      hyporesponsive in comparison to healthy, adult immune competent individuals. One population
      of immune compromised Canadians at risk for severe influenza disease is those living with HIV
      infection. At least 56,000 Canadians are HIV infected [1]. This population is at risk for
      more severe influenza illness. Influenza viral replication and shedding is prolonged and the
      duration of influenza symptomatology is longer in those with HIV [2, 3]. Furthermore,
      influenza-related mortality rates in HIV infected individuals are increased [4]. The HIV
      population is known to be hyporesponsive to vaccinations, including influenza. The efficacy
      of influenza vaccines is compromised, in part, by reduced antibody responses observed in HIV
      infected individuals [5]. Nevertheless, influenza vaccination is recommended for HIV-infected
      individuals [6, 7]. The Centers of Disease Control guidelines state: "Influenza can result in
      serious illness and because vaccination with inactivated influenza vaccine might result in
      the production of protective antibody titers, vaccination might benefit HIV-infected persons.
      Therefore, influenza vaccination is recommended". As influenza vaccination is the cornerstone
      of public health interventions intended to protect the population against influenza, vaccine
      hyporesponsiveness in immune compromised populations represents a significant concern. Given
      the risk of influenza exposure in general as well as concerns related to poor vaccine
      efficacy and more severe influenza disease in immune compromised populations such as those
      living with HIV, strategies to improve vaccine efficacy are required.

      Therefore a total of 5 conditions provide justification for a trial to be conducted at this
      time:

        1. current standard treatment with influenza vaccine is less efficacious when used in
           particular subgroups of immune compromised individuals, such as those diagnosed with HIV

        2. there exists a significant burden of influenza infection in HIV patients that must be
           addressed in terms of identifying an effective treatment strategy

        3. past randomized trials of influenza vaccination in HIV patients are of limited
           comparability to today's relevant base of patients, and alternative vaccination
           strategies require assessment

        4. efficacy of booster doses of influenza vaccine in HIV patients remains in question as a
           consequence of methodologic shortcomings in terms of both design aspects and outcomes
           measured of past studies

        5. there is a paucity of published evidence assessing the efficacy of an increased,
           double-dose of influenza vaccine in this patient population.

      References

        1. Boulos, D., et al., Estimates of HIV prevalence and incidence in Canada, 2005. Can
           Commun Dis Rep, 2006. 32(15): p. 165-74.

        2. Safrin, S., J.D. Rush, and J. Mills, Influenza in patients with human immunodeficiency
           virus infection. Chest, 1990. 98(1): p. 33-7.

        3. Radwan, H.M., et al., Influenza in human immunodeficiency virus-infected patients during
           the 1997-1998 influenza season. Clin Infect Dis, 2000. 31(2): p. 604-6.

        4. Zanetti, A.R., et al., Safety and immunogenicity of influenza vaccination in individuals
           infected with HIV. Vaccine, 2002. 20 Suppl 5: p. B29-32.

        5. Malaspina, A., et al., Compromised B cell responses to influenza vaccination in
           HIV-infected individuals. J Infect Dis, 2005. 191(9): p. 1442-50.

        6. Health Canada Progress towards Canadian target coverage rates in Influenza and
           Pneumococcal Immunications., in Available at:
           http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/01vol27/dr2710eb.htlm. Accessed 8 December
           2006. 2006.

        7. Prevention and Control of Influenza. Recommendations of the advisory committee on
           immunization practice, in Centers for Disease Control and Prevention. Morbidity and
           Morality Weekly Report. 2006. p. Vol 55/RR-10.
    

Intervention name(s): Fluviral
Intervention type(s): Biological
Other intervention name(s): non applicable
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Prevention
Keywords: Influenza; HIV; Influenza Vaccine; Efficacy