This study is designed to assess safety and immunogenicity of four dose formulations of cytomegalovirus (CMV) vaccine (0.5 μg gB content with aluminum phosphate (alum), 1.0 μg glycoprotein B (gB) content with alum, 2.0 μg gB content with alum, or 1.0 μg gB content (without alum) as compared with placebo in approximately 125 healthy CMV-seronegative volunteer participants between 18 and 40 years of age.