Live Attenuated Influenza Vaccine (LAIV) Versus Trivalent Inactivated Influenza Vaccine in Healthy Adults 18-49 Years
Condition: Influenza
MeSH terms: Influenza, Human
Study type: Interventional
Phase: Phase 4

Summary: 
      This randomized, open-label, single-site study at Saint Louis University will enroll
      approximately 40 subjects who are healthy, 18 to 49 years old. Subjects will be randomized in
      a 1:1 fashion to receive either licensed trivalent FluMist containing (2010-2011 season
      appropriate), or licensed inactivated trivalent influenza vaccine (2010-2011 season
      appropriate) so that approximately 20 subjects will be randomized to receive LAIV, and 20
      will receive IIV.
    

Detailed description: 
      This Phase IV, randomized, open-label, single-site study at Saint Louis University will
      enroll approximately 40 subjects who are healthy, 18 to 49 years old. Subjects will be
      randomized in a 1:1 fashion to receive either licensed inactivated influenza vaccine (IIV)
      (2010-2011 season appropriate) or licensed live attenuated influenza vaccine (LAIV)
      (2010-2011 season appropriate) so that approximately 20 subjects will be randomized to
      receive IIV, and 20 will receive LAIV. Subjects will receive 1 dose of IIV or LAIV in the
      Center for Vaccine Development on Day 0 and will return to the site on days 7 and 45 to
      assess immunogenicity. Subjects will be asked to report any serious adverse events. Blood
      samples and nasal washes for assessment of immune responses will be obtained at three time
      points: on Day 0 prior to dosing with IIV or LAIV, and at visits conducted 7 and 45-51 days
      post vaccination. The study will be conducted just prior to and during the influenza season.
      Subjects will receive a single dose of IIV or LAIV administered as instructed per package
      insert. Two contacts will be made with subjects, either telephone calls or e-mail, to collect
      serious adverse events only, one at Days 28-35, and one at approximately Days 180-190 to
      conclude the subject's participation. The duration of each subject's participation is
      approximately 6 months. The primary immune studies conducted with collected samples will
      include serum hemagglutinin inhibition (HAI) antibody titers, nasal wash influenza-specific
      secretory immunoglobulin A (IgA) responses, peripheral blood interferon gamma (IFN-γ) ELISPOT
      assays and peripheral blood carboxyfluorescein succinimidyl ester (CFSE)
      dilution/intracellular cytokine staining flow cytometric assays. In addition, frozen serum
      and peripheral blood mononuclear cells (PBMC) samples will be used in exploratory assays to
      determine the kinetics and nature of innate responses and the detailed molecular signatures
      of memory T cells induced by IIV and LAIV vaccinations. Investigators will be performing
      genome-wide expression studies, but will not perform DNA sequencing and will not send
      anything other than coded samples outside of Saint Louis University.
    

Intervention name(s): Inactivated Influenza Vaccine; Live Attenuated Influenza Vaccine
Intervention type(s): Biological; Biological
Other intervention name(s): IIV; LAIV
Intervention MeSH terms: Vaccines
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Subjects will be randomized to one of two different groups to receive either licensed inactivated influenza vaccine (IIV) or licensed live attenuated influenza vaccine (LAIV) from the 2010-2011 season.
Masking: None (Open Label)
Primary purpose: Prevention