Cellular and Humoral Immune Response to Primary and Secondary Immunization With Subvirion H5N1 Vaccines
Condition: Influenza
MeSH terms: Influenza, Human; Influenza in Birds
Study type: Interventional
Phase: Phase 1

Summary: 
      The purpose of the study is to evaluate safety and compare how the body reacts to 2 different
      strengths of the Clade (specific type of H5N1 virus) 2 H5N1 flu vaccine when given as a
      single vaccination with a high dose (90 mcg) or low dose (15 mcg) to volunteers who have
      received at least 2 doses of the Clade 1 H5N1 vaccine, in a previous National Institute of
      Health study or who have never received a H5N1 vaccine (naïve). Previously vaccinated
      subjects (in studies 04-0063, 05-0090, 05-0127) will receive either 15 or 90 mcg of H5N1
      vaccine. Multiply boosted volunteers who participated study 05-0043 and received Clade 1 and
      3 vaccines, will receive the same dose (15mcg). Vaccine naïve subjects will receive 2 doses
      of vaccine (15 or 90 mcg) separated by 28 days. Blood samples will be collected. 115
      volunteers age 18-64 may participate in study related procedures for approximately 7 months.
    

Detailed description: 
      In response to the steadily increasing number of reports of human infection with avian
      influenza A (H5N1) viruses, there is now a world-wide effort to develop and test potential
      candidate vaccines for this and other avian viruses with pandemic potential. The study will
      be conducted as a laboratory blinded assessment of the humoral and cellular immune response
      to A/Indonesia/5/05 vaccine in three populations: healthy adults who have previously received
      a clade 1 H5 vaccine in a Division of Microbiology and Infectious Diseases (DMID)-sponsored
      study; healthy adult recipients of prime-boost regimens representing two clades; and healthy
      adults with no previous H5 vaccination and who are not at risk for H5 exposures. Primed
      subjects are randomized to receive a single dose of either 15 mcg or 90 mcg of
      A/Indonesia/5/05 vaccine. Multiply boosted subjects are those who participated in study
      05-0043, and have previously received both A/HK/97 (Clade 3) and A/VN/04 (Clade 1) vaccines.
      Because only a small number of such subjects are available, they will not be randomized but
      will all receive the same dose of vaccine. Unprimed subjects are randomized to receive 2
      doses of 15 mcg or 90 mcg of A/Indonesia/5/05 vaccine separated by 28 days. In all groups,
      sera and peripheral blood mononuclear cells (PBMC) are obtained prior to and on days 3, 7,
      14, and 28 after each dose. Primed and multiply boosted subjects also have sera and PBMC
      obtained on day 56. All groups will make a final study visit at 6 months following the last
      dose of vaccine (day 180 for primed and boosted subjects and day 208 for unprimed subjects).
      Approximately 115 subjects between the ages of 18 and 64 will participate in this study. The
      primary objective is to determine the safety of administration of the A/Indonesia/05
      subvirion vaccine when administered to healthy, primed or unprimed adults. The secondary
      objective is to: determine the effects of priming with a clade 1 vaccine on antibody
      responses to revaccination with a clade 2 vaccine. The tertiary objectives are to determine
      the effects of priming on the repertoire and phenotypes of B and T cells generated in
      response to vaccination; to evaluate whether pre-existing immunity to seasonal influenza
      viruses impacts the specificity and magnitude of the cluster of differentiation marker (CD)4
      T cell response to H5 vaccination and to describe the kinetics of the cellualr immune
      response to subvirion H5N1 vaccinatin in primed and unprimed individuals. The primary
      endpoint is reactogenicity, adverse event (AE) and serious adverse event (SAE) information,
      solicited in-clinic and via memory aids. The secondary endpoints are: levels of HAI antibody
      recognizing A/Indonesia/05 (Clade 2), A/Vietnam/04 (Clade 1) and representative Clade 2
      subclade viruses, and levels of neutralizing antibody assessed by neutralization tests using
      the rgA/Indonesia/5/05 virus prior to and Days 3, 7, 14, and 28 after each vaccination. This
      study is linked to DMID protocols 04-063, 05-0090, 05-0043 and 05-0127.
    

Intervention name(s): Influenza Virus Vaccine, Monovalent A/H5N1 A/Indonesia/05/2005
Intervention type(s): Biological
Intervention description(s): Inactivated monovalent subvirion H5N1 vaccine (HA of A/Indonesia/05/05) provided in unit-dose vials containing 0.5 mL of either 30 mcg/mL A/H5N1 HA or 180 mcg/mL A/H5N1 HA. Subjects will receive 1 of 2 dose levels of vaccine, 15 or 90 mcg.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Prevention
Keywords: Influenza, H5N1, avian influenza, parent protocol