This is a phase 1, First in Humans, randomized (2:2:1) observer blind, controlled, dose ranging, multi-arm parallel-group clinical trial in healthy persons 50 to 64 years of age to assess the safety and immunogenicity of two dose levels of a novel vaccine formulation DPX-RSV(A) consisting of a synthetic Respiratory Syncytial Virus SHe antigen combined with a novel adjuvant DepoVaxTM, compared to the antigen combined with the commonly used adjuvant Aluminum hydroxide, and to a saline placebo control.~The study will evaluate two different doses of DPX-RSV(A) and two doses of the RSV SHe antigen with aluminum hydroxide (RSV(A)-Alum), and a placebo control. The study is randomized, controlled, and observer-blinded in order that allocation to treatment is concealed from the investigative team and the participant. The inclusion of comparator groups (a placebo control group and the RSV(A)-Alum) allows for estimation of the attributable risk of adverse events. Since the study vaccines are not identical in appearance, an unblinded study nurse who has no other role in the study will administer the study vaccines.
Administration of DPX-RSV(A), a Respiratory Syncytial Virus vaccine containing Respiratory Syncytial Virus (RSV) SHe antigen and DepoVaxTM adjuvant to healthy adults ≥50-64 years of age.