H5 Booster After a Two Dose Schedule
Condition: Influenza
MeSH terms: Influenza, Human
Study type: Interventional
Phase: Phase 2

Summary: 
      The purpose of this study is to determine whether a third dose of vaccines containing
      A/Vietnam/1203/04 provides more immunity than two doses. Subjects who participate in this
      study will have participated in DMID protocol 04-063 involving the A/Vietnam/1203/04. In this
      study, each subject will be asked to receive a third dose of the H5 vaccine at the same level
      administered in protocol 04-063. Subjects will be asked to record oral temperature and any
      experienced side effects for 7 days following the vaccine. Study procedures will include up
      to 3 blood sample collections. Participants will be involved in study related procedures for
      up to 6 months.
    

Detailed description: 
      This study is linked to DMID protocols 04-063, 07-0022 and 08-0059. DMID Study 05-0090 is an
      extension study to DMID Study 04-063. Between March and May 2005, DMID Study 04-063 enrolled
      approximately 450 subjects at three study sites. Subjects were stratified by age and history
      of prior influenza vaccination for the 2004-2005 season, and randomly assigned to receive 2
      doses of saline placebo (N=50) or 7.5, 15, 45, or 90 mcg of the influenza A/H5N1 virus
      vaccine (N=100/dose group) by IM injection. Approximately 6 months after receiving their
      second vaccination, subjects enrolled in DMID Study 04-063 will return to the clinic for
      their final study visit (Visit 6). After completing this visit, which includes collection of
      safety data and a 30-mL blood draw, the unblinded vaccine administrator will determine if the
      study subject received placebo or the influenza A/H5N1 vaccine. In the proposed extension
      study (DMID Study 05-0090), subjects who received the influenza A/H5N1 vaccine will be
      provided with information about DMID Study 05-0090 and asked if they are willing to receive a
      third dose of vaccine at the same dose level originally administered (i.e., those subjects
      originally receiving two doses of 7.5 mcg will receive a single booster dose of 7.5 mcg,
      those receiving two doses of 15 mcg will receive a single booster of 15 mcg, etc.). Subjects
      that provide informed consent and are eligible for DMID Study 05-0090 will be given a third
      dose of the vaccine at the same dose level they previously received by the unblinded vaccine
      administrator. Symptoms and signs will be assessed in the clinic for 15 to 30 minutes after
      inoculation, and the subjects will maintain a memory aid to record oral temperature and
      systemic and local adverse events (AEs) for 7 days after each immunization. Subjects will be
      encouraged to take their temperature around the same time each day. All subjects will receive
      a safety follow-up telephone call at 1 to 3 days to elicit any AE information and between 13
      to 19 days after the vaccination to elicit any AE information and review the memory aid.
      Subjects will return to the clinic 28 (+/- 3) days after vaccination for assessment of AEs
      and concomitant medications, targeted physical examination (if indicated) and blood sample
      collection. During this follow-up visit, subjects who have been identified as "high
      responders" to the vaccine in the DMID 04-063 study will also be solicited to participate in
      a blood specimen collection substudy. Subjects will be provided with information about the
      substudy and asked if they would consent to have an additional 100 mL of blood drawn after
      the blood sample is collected for serum antibody assays. Refusal to consent for this substudy
      does not preclude subjects from continuing in the booster vaccine trial. At approximately Day
      180 (6 months after booster vaccination), subjects will return to the clinic for a final
      immunogenicity blood sample collection and for follow-up, which may include a targeted
      physical examination (if indicated). The duration of the study treatment for each subject in
      this study will be about 6 months.
    

Intervention name(s): Inactivated Influenza A/H5N1 Vaccine (sanofi pasteur)
Intervention type(s): Biological
Intervention description(s): A monovalent subvirion H5N1 vaccine (HA of A/Vietnam/1203/04) provided in unit¿¿dose vials containing either 30-mcg/mL A/H5N1 HA or 90-mcg/mL A/H5N1 HA. Subjects will receive 1 of 4 dose levels of vaccine (7.5, 15, 45, or 90 mcg) administered intramuscularly.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Avian influenza, vaccine, A/H5N1, sub-study