This study was terminated and study objectives, endpoints, and procedures were modified accordingly via Protocol Amendment 03. Analysis included the intervention doses (V590 5.00 x 10^5 plaque forming units [pfu], V590 2.4 x 10^6 pfu, V590 1.15 x 10^7 pfu, V590 5.55 x 10^7 pfu or placebo) as specified in the protocol.
The primary objective of this study is to evaluate the safety and tolerability of V590 versus placebo and to assess the immunogenicity of V590 on Day 28. The primary hypothesis is that at least one well-tolerated dose of V590 increases the geometric mean titers (GMTs) of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike serum neutralizing antibody, as measured by plaque reduction neutralization test (PRNT), compared to placebo.