H1N1 Vaccine in Pregnant Women
Condition: Influenza
MeSH terms: Influenza, Human
Study type: Interventional
Phase: Phase 2

Summary: 
      The purpose of this study is to evaluate an investigational 2009 H1N1 influenza vaccine to
      determine vaccine safety in pregnant women and the body's immune response (body's defense
      against disease) to different strengths of the H1N1 influenza vaccine. In this study, 2
      strengths of the H1N1 influenza vaccine will be tested (given 3 weeks apart). Participants
      will include approximately 120 healthy pregnant women, ages 18-39 years, in their second or
      third trimester of pregnancy (14-34 weeks gestation). Study procedures will include 2 doses
      of vaccine, blood samples, cord blood samples at delivery, and recording temperature and
      vaccine side effects in a memory aid for 8 days following each vaccination. Participants will
      be involved in study related procedures for about 7 months.
    

Detailed description: 
      Recently, a novel swine-origin influenza A/H1N1 virus was identified as a significant cause
      of febrile respiratory illnesses in Mexico and the United States. It rapidly spread to many
      countries around the world, prompting the World Health Organization to declare a pandemic on
      June 11, 2009. Data from several cohorts in different age groups that received licensed
      trivalent seasonal influenza vaccines suggest that these vaccines are unlikely to provide
      protection against the new virus. In addition, adults are more likely to have measurable
      levels of serum hemagglutination inhibition assay (HAI) or neutralizing antibody than are
      children. These data indicate the need to develop vaccines against the new H1N1 strain and
      suggest that different vaccine strategies (e.g., number of doses, need for adjuvant) may be
      appropriate for persons in different age groups. Pregnant women are at an increased risk for
      the complications of influenza. A higher dose or multiple doses of an unadjuvanted,
      inactivated influenza H1N1 vaccine may be necessary to confer protection to this at risk
      population. This protocol will explore the antibody response following vaccination of
      pregnant women at 2 different dose levels (15 mcg and 30 mcg). The 2 doses of inactivated
      influenza H1N1 vaccine will be administered 21 days apart. This study will assess the immune
      response following a single dose of H1N1 vaccine, to assess whether individuals have any
      pre-existing "prime" immunity, such that the initial H1N1 vaccination serves as a boost, thus
      conferring a more rapid time to protection with the need for fewer doses. Antibody responses
      will be assessed 21 days after each dose. The primary objectives are: safety, to assess the
      safety of unadjuvanted, inactivated H1N1influenza vaccine in pregnant women when administered
      at the 15 mcg or 30 mcg dose; and immunogenicity, to assess the antibody response following a
      single dose of unadjuvanted, inactivated H1N1 influenza vaccine in pregnant women when
      administered at the 15 mcg or 30 mcg dose. The secondary objectives are to: assess the
      antibody response following 2 doses of unadjuvanted, inactivated H1N1 influenza vaccine in
      pregnant women when administered at the 15 mcg or 30 mcg dose; and assess the efficiency of
      placental transport of maternal influenza antigen specific antibodies to the neonate. This is
      a randomized, double-blinded, phase II study in 120 pregnant women, ages 18-39 years.
      Subjects will be randomized into 2 groups (60 pregnant women per dose group) to receive
      intramuscular inactivated influenza H1N1 vaccine at 15 mcg (Group 1) or 30 mcg (Group 2) on
      Days 0 and 21. Following immunization, safety will be measured by assessment of adverse
      events through 21 days following the last vaccination (Day 42), serious adverse events and
      new-onset chronic medical conditions through 7 months post first vaccination (Day 201).
      Reactogenicity to the vaccine will be assessed for 8 days following each vaccination (Day
      0-7). Immunogenicity testing will include HAI and neutralizing antibody testing on serum
      obtained on Days 0, 21 and 42. This includes samples collected prior to each vaccination and
      samples collected 21 days following each vaccination. HAI antibody testing will be also be
      performed on serum from maternal and cord blood collected at delivery.
    

Intervention name(s): Inactivated H1N1 Vaccine
Intervention type(s): Biological
Intervention description(s): Two doses of inactivated influenza H1N1 vaccine delivered intramuscularly (IM) as 15 or 30 mcg dose. The 15 mcg dose will be administered as a single 0.5 mL IM injection in the deltoid muscle of the preferred arm. The 30 mcg dose will be administered as a single 1.0 mL injection in the deltoid muscle.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: H1N1, influenza A viruses, pregnant women