A Study of Safety, Tolerability, and Immunogenicity of the MRKAd5 Gag/Pol/Nef Vaccine in Healthy Adults (V520-016)
Condition: HIV-1; HIV Infections
MeSH terms: HIV Infections
Study type: Interventional
Phase: Phase 1

Summary: 
      The goal of this study is to understand the safety, tolerability and immunogenicity of the
      Merck Trivalent Adenovirus Serotype 5 HIV-1 gag/pol/nef

      Vaccine (MRKAd 5 HIV-1 gag/pol/nef) vaccine in healthy human volunteers compared to placebo.
      The study will also evaluate a number of dose levels and the necessity for and timing of
      booster injections.
    

Detailed description: 
      The study will proceed in four stages. Following stages I, II and III, all subjects will have
      the Postdose 1 (PD1) clinical and laboratory safety data reviewed by the Safety Evaluation
      Committee (SEC). If these data are acceptable, the next stage will be initiated.

        -  In Stage I, participants will be randomized to receive 3 doses of the 3x10^9vp/dose
           level Trivalent vaccine or placebo.

        -  In Stage II, participants will be randomized to receive 2 or 3 doses of the
           3x10^10vp/dose level Trivalent vaccine or placebo.

        -  In Stage III, participants will be randomized to receive 3 doses of the Trivalent
           vaccine with titers of 1x10^11vp/dose, 3x10^6vp/dose, 3x10^7vp/dose, or 3x10^8vp/dose or
           placebo.

        -  In Stage IV, participants will be randomized to all treatment groups. In addition, some
           participants will be randomized to an MRKAd 5 HIV-1 gag Monovalent vaccine. In this
           stage, participants will be pre-stratified by baseline Ad5 titers (=<200, and >200), to
           ensure an even distribution of participants with high and low Ad5 titers across the
           various treatment groups.
    

Intervention name(s): Comparator: Placebo to the MRKAd5 HIV-1 gag/pol/nef vaccine; Monovalent MRKAd5 HIV-1 gag vaccine (1x10^9 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^6 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^7 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^8 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^9 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^10 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (1x10^11 vp/dose); Comparator: Placebo to MRKAd5 HIV-1 gag vaccine
Intervention type(s): Other; Biological; Biological; Biological; Biological; Biological; Biological; Biological; Biological
Intervention description(s): Placebo to the MRKAd5 HIV-1 gag/pol/nef vaccine.; Monovalent MRKAd5 HIV-1 gag vaccine (1x10^9 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^6 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^7 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^8 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^9 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (3x10^10 vp/dose); Trivalent MRKAd5 HIV-1 gag/pol/nef vaccine (1x10^11 vp/dose); Placebo to the MRKAd5 HIV-1 gag vaccine.
Other intervention name(s): V520; V520; V520; V520; V520; V520; V520
Intervention MeSH terms: Vaccines
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Prevention
Keywords: HIV Seronegativity; Preventive Vaccine