To Evaluate Safety and Immunogenicity of a Prophylactic Plasmid DNA

Phase 1 is the randomized, observer-blinded, multi-center, dose-finding part of the study, followed by an adaptive Phase 2 in which the optimal dose, determined from Phase 1, will be evaluated for safety and efficacy. In Phase 1 up to 50 participants are planned to be randomized 1:1 into one of two groups: either 100 μg intramuscular (IM) injection or 250 μg IM injection. Participants are to receive a single 0.5 mL IM injection of VAX-002 100 μg or 250 μg on Day 0. Follow-up visits will occur on Days 7, 14, 17 (phone call visit), 21, 28, 42, and 180. An interim analysis is planned once all participants in Phase 1 have completed their Day 28 visit to evaluate dose-response and safety to support optimal dose selection for Phase 2. In Phase 2 approximately 250 participants will be enrolled and will receive a single 0.5 mL IM injection of the optimal VAX-002 dose (determined in the Phase 1 interim analysis) on Day 0. Follow- up visits will occur on Days 7, 14, 17 (phone call visit), 21, 28, 42, and 180.