Randomized, double blind, multi-site, study in healthy adults, comparing safety and
immunogenicity of two dosage levels of Norwalk VLP Vaccine with adjuvant/excipients and with
placebo controls
Primary Objective:
- Safety as determined by occurrence of local intranasal symptoms or other symptoms as
reported by a self-administered memory aid for 7 days after each vaccination and
hematology, blood chemistry and physical examinations performed by the clinical research
staff
- Subjects will also be monitored for Serious Adverse Events (SAEs), and onset of any new
medical conditions for 180 days following the last study vaccinations (Day 201).
Secondary Objectives
Evaluations of immunogenicity as determined by:
- Geometric mean titers and seroconversion rate of serum anti- Norwalk VLP IgG and IgA
- Stimulation of anti-Norwalk VLP IgA antibody secreting cells (ASC)
- Presence of antigen specific memory B-cell response
Cells will be collected and stored for possible future evaluation of Norwalk VLP-specific
cell-mediated immune (CMI) responses
Study Hypothesis:
The incidence of adverse events after intranasal Norwalk VLP Vaccine will be the same as the
incidence of adverse events after intranasal adjuvant/excipients alone. Norwalk VLP Vaccine
and adjuvant/excipients will have a higher incidence of mild to moderate nasal adverse events
compared to placebo but similar incidence of other adverse events.
Two doses of the 100 µg of Norwalk VLP Vaccine will be more immunogenic than two doses of 50
µg of Norwalk VLP Vaccine. The post-vaccination serum antibody responses, the number of
antibody secreting cells (ASC) and IgG and IgA memory B-cell responses directed against
Norwalk Virus antigen will be increased after Norwalk VLP Vaccine compared to
adjuvant/excipients and to placebo.