Open-Label Study of H5 Vaccine in Participants of Protocol 04-077
Condition: Influenza
MeSH terms: Influenza, Human
Study type: Interventional
Phase: Phase 1/Phase 2

Summary: 
      This study may provide safety information on a flu vaccine given to children and may provide
      immunogenicity information to add to what was collected in a previous flu vaccine study.
      Participants will include 55 healthy children, ages 2-10, who participated in 04-077 and
      received a placebo injection instead of the flu vaccine or were incompletely immunized. The
      study has 2 purposes: to make sure there are no serious side effects in children and to see
      how the immune systems react to the vaccine. Study procedures include up to 4 study visits,
      up to 9 follow-up phone calls, 2 blood samples to be collected during visits 1 and 3, and up
      to 3 vaccine injections in the arm or thigh muscle. Parents will be given a memory aid card
      to record side effects, temperatures, and medications. Parents will have the option for the
      child to receive a 3rd dose of vaccine if offered, at month 6. This booster shot will require
      a 6-month visit and participation for an additional 6 months.
    

Detailed description: 
      The recent emergence of novel influenza virus strains in human populations has encouraged
      efforts to develop vaccines for a potential pandemic. The objectives of this study are to
      evaluate the safety of intramuscular (IM) subvirion inactivated H5N1 vaccine in healthy
      children aged 2 through 10 years and to determine the immunogenicity profile of IM subvirion
      inactivated H5N1 vaccine in healthy children approximately 1 month following receipt of the
      second of 2 doses of vaccine. Study endpoints include: adverse event (AE) and serious adverse
      event (SAE) information (solicited in-clinic and via memory aids, concomitant medications,
      and periodic targeted physical assessments, as indicated); proportion of subjects achieving a
      serum hemagglutination inhibition antibody titer of 1:40 against the influenza A/H5N1 virus
      28 days after receipt of second dose of vaccine (approximately Day 56); geometric mean titer
      and the frequency of 4-fold or greater increases in hemagglutination inhibition antibody
      titers 28 days after receipt of second dose of vaccine (approximately Day 56); and
      development of serum antibody responses against antigenically drifted variants of influenza
      H5N1 virus. This study is linked to DMID protocol 06-0072. Up to 55 healthy children, aged 2
      through 10 years, who previously participated in DMID 04-077, will be eligible for enrollment
      in this multimember, open-label, phase I/II clinical trial to receive at least 2 and up to 3
      doses of an inactivated influenza A/H5N1 vaccine at a 45-micrograms dose. The vaccine dosage
      level that will be used in this study was chosen based upon safety and immunogenicity data
      collected previously in adults and children. The injection volume of the 90-micrograms dose
      is 1 mL for the vaccine being used in this study, but this is considered unacceptable in this
      age group. Therefore, the 45-micrograms dose (0.5 ml volume) has been selected. Twenty three
      subjects who were previously enrolled and assigned to placebo in the DMID 04-077 study (A
      Randomized, Double-Blinded, Placebo-Controlled, Phase I/II, Study of the Safety,
      Reactogenicity, and Immunogenicity of Intramuscular Inactivated Influenza A/H5N1 Vaccine in
      Healthy Children Aged 2 Years Through 9 Years) along with up to 32 subjects from a single
      site who were incompletely immunized are eligible for enrollment in this study. Vaccine will
      be administered into the deltoid or (if age appropriate) thigh muscle. All subjects will
      receive 2 doses of the vaccine approximately 28 days apart. At month 6, subjects' parent(s)
      or guardian(s) will be called to assess the subjects for serious adverse events. Blood
      collection for immunogenicity studies will be at the discretion of the parent(s) or legal
      guardian(s). Should data evaluating a third dose of the influenza A/H5N1 vaccine show
      enhanced immunogenicity in pediatric subjects participating in DMID 04-077, parents/guardians
      of subjects who received vaccine will be offered the possibility of a third dose for their
      participating children.
    

Intervention name(s): Inactivated Influenza A/H5N1 Vaccine (sanofi pasteur)
Intervention type(s): Biological
Intervention description(s): Inactivated influenza A/H5N1 vaccine administered via intramuscular (IM) injection; dosage 45-mcg.
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: influenza, A/H5N1, avian influenza, vaccine