Rabies vaccine(Sanofi)

This is single site, randomized, blinded comparison of the immunogenicity, of Imovax (RVi) and Rabavert (RVa) rabies vaccines when subjects are administered rabies immune globulin (RIG) or SYN023. Subjects will be randomized into one of four dose groups: RVi + SYN023, RVi+RIG, RVa+SYN023 and RVa+RIG. The initial dose of RVi and RVa will be co-administered with either RIG or SYN023). Rabies virus neutralizing activity (RVNA) and blood levels of SYN023 will be measured for the remainder of the trial while the rest of the five RVi and RVa doses are given. The study will last 112 days. SYN023 concentrations and anti-SYN023 antibodies will also be measured.

The aim of the study is to document the safety and immunogenicity of Purified Vero Rabies Vaccine (VRVg) when given in a simulated post-exposure regimen, i.e. with co-administration of human rabies immunoglobulins (Imovax® Rabies).
Primary Objectives:
To demonstrate that VRVg is non-inferior to Imovax® Rabies in terms of proportion of subjects achieving a rabies virus neutralizing antibody (RVNA) titer ≥ 0.5 international units (IU)/mL at Day 14.
To demonstrate that the observed proportion of subjects achieving an RVNA titer ≥ 0.5 IU/mL at Day 14 is at least 99%, with a lower limit of the 95% confidence interval (CI) of at least 97%.
Secondary Objectives:
To assess the clinical safety of each vaccine after each vaccine injection when administered in a simulated post-exposure schedule.
To describe the geometric mean titer ratio (GMTR) between the 2 vaccine groups at Day 14.