Safety of a Live Attenuated Human Parainfluenza Virus Type 2 (HPIV2) Vaccine for Adults, Children, and Infants
Condition: Human Parainfluenza Virus 2
MeSH terms: Paramyxoviridae Infections
Study type: Interventional
Phase: Phase 1

Summary: 
      Human parainfluenza virus type 2 (HPIV2) can result in severe respiratory illness in infants
      and young children. This study will test the safety of and immune response to an HPIV2
      vaccine aimed at infants and children.
    

Detailed description: 
      HPIV2 is a virus that can cause severe respiratory illnesses, such as pneumonia and
      bronchiolitis, in infants and young children. Approximately 3% of all hospitalizations for
      respiratory tract diseases among infants and children are the result of HPIV2. Efforts to
      develop a vaccine for HPIV2 have focused on a live attenuated intranasally administered
      vaccine, a type of vaccine that uses a live virus that has been modified to make it weaker
      and easier for the immune system to get rid of. This approach is useful for several reasons:
      it activates two of the body's natural defenses, the antibody-mediated and the cell-mediated
      responses; it is immunogenic in infants who still have maternal antibodies; and it induces a
      mucosal immune response. This study will test the safety and immunogenicity of an HPIV2
      vaccine in adults, children, and then infants.

      This study will have four groups and will proceed in a step-wise fashion. The first group
      will consist only of adults receiving the HPIV2 vaccine. If it is deemed safe after that,
      children from ages 15 to 59 months who already have HPIV2 antibodies will be randomly
      assigned to receive either the vaccine or a placebo. The third group includes infants and
      children from 6 to 59 months old who do not have HPIV2 antibodies and will be randomly
      assigned either a lower dose of the vaccine or a placebo. The fourth group also includes
      infants and children from 6 to 59 months old who do not have HPIV2 antibodies and will be
      randomly assigned a standard dose vaccine or placebo. The vaccine will be administered as a
      nose drop in a single dose for all groups.

      Assessments for the first two groups will take place over the 11 days following
      administration of the vaccine and at a 28-day follow-up. The third and fourth groups will
      include 22 days of assessments after vaccination, one assessment between Days 23 and 26, and
      assessments on Days 27, 28, 29, and 56. Measures will include a clinical assessment, a nasal
      wash, a phone report, and taking a temperature. Measurement of serum HPIV2 antibodies will
      take place at baseline and after 28 (for groups one and two) or 56 (for groups three and
      four) days.
    

Intervention name(s): Standard Dose HPIV2 Vaccine; Low dose HPIV2 vaccine; Placebo
Intervention type(s): Biological; Biological; Other
Intervention description(s): 10^6 tissue culture infectious dose 50% (TCID50) administered intranasally in a single dose; 10^5 TCID50 administered in a single dose; Matched placebo
Intervention MeSH terms: Vaccines
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Care Provider)
Primary purpose: Prevention
Keywords: Vaccine; HPIV2; Infants