B-19 Parvovirus Vaccine Study

This study is a Phase I/II randomized, placebo-controlled, double-blind clinical trial of the immunogenicity and safety of 2 dose levels of a recombinant human parvovirus B-19 vaccine (VAI-VP705). The vaccine is composed of viral capsids that incorporate 2 B-19 proteins (VP-1 and VP-2). There will be 3 sites participating in this study: Cincinnati Children's Hospital Medical Center, Baylor College of Medicine, and the University of Maryland School of Medicine. Eighty-nine parvovirus B-19 seronegative healthy adults 18-45 years old will be randomized to 1 of 4 groups: 2.5 mcg VAI-VP705 with the adjuvant MF59, 25 mcg with the adjuvant MF59, 25 mcg without the adjuvant MF59, or placebo (saline control). Each participant will receive 3 separate vaccinations (Months 0, 1, and 6) and will continue in the study for up to approximately 14 months. Study participants will be followed to evaluate safety and immune response. The primary study objective is to evaluate the safety of VAI-VP705 administered with and without MF59 adjuvant in healthy parvovirus B-19 seronegative adults. The secondary study objectives are to: evaluate the immunogenicity of primary and booster immunizations of 25 mcg of VAI VP705 with and without MF59 and 2.5 mcg with MF59; compare the antibody response of vaccine administered with MF59 at each of 2 doses, 2.5 and 25 mcg versus 25 mcg of vaccine administered without MF59; and evaluate the duration of the immune response 12 months after primary immunization. The primary endpoint is the number and percentage of study participants who experience any vaccine-associated adverse events or serious adverse events. The secondary endpoints include: the percentage of study participants who develop neutralizing antibody responses against parvovirus B-19 28 days following the last dose of vaccine; the percentage of study participants who maintain a neutralizing antibody titer at 12 months after primary immunization; the geometric mean antibody titers (as measured by enzyme-linked immunosorbent assay) by treatment group at 28 days and at 12 months after primary immunization; and the geometric mean neutralizing titers per treatment group at 28 days and at 12 months after primary immunization.