Safety of and Immune Response to a DNA HIV Vaccine Followed By an Adenoviral Vector HIV Vaccine in Healthy Adults

• Local and systemic adverse reactions [ Time Frame: Measured after each injection and for 12 months after the first injection ] [ Designated as safety issue: Yes ]
  
• Unfractionated IFN-γ ELISpot responses to HIV-1 peptide pools as performed by the VRC laboratory [ Time Frame: Measured at Day 196 ] [ Designated as safety issue: No ]
  
• Unfractionated IFN-γ ELISpot responses to HIV-1 peptide pools as performed by the FHCRC laboratory [ Time Frame: Measured at Day 210 ] [ Designated as safety issue: No ]
  
• CD4 and CD8 T cell responses to HIV-1 peptide pools as measured by flow cytometry-based intracellular cytokine staining (ICS) assay as performed by the VRC laboratory [ Time Frame: Measured at Day 196 ] [ Designated as safety issue: No ]
  
• CD4 and CD8 T cell responses to HIV-1 peptide pools as measured by flow cytometry-based ICS assay as performed by the FHCRC laboratory [ Time Frame: Measured at Day 210 ] [ Designated as safety issue: No ]
  

• Humoral immune response to HIV-1 as measured by neutralizing antibody and binding assays [ Time Frame: Measured through Month 36 ] [ Designated as safety issue: No ]
  
• Unfractionated IFN-γ ELISpot responses to HIV-1 as performed by the FHCRC or the VRC laboratories [ Time Frame: Measured at Days 70, 210, and 364 ] [ Designated as safety issue: No ]
  
• CD4 and CD8 T cell responses to HIV-1 as measured by flow cytometry-based ICS assay as performed by the FHCRC or the VRC laboratories [ Time Frame: Measured at Days 70, 210, and 364 ] [ Designated as safety issue: No ]
  
• Vaccine-induced HIV-specific T cell responses to individual peptide pools as measured by IFN-γ ELISpot and ICS as performed by the FHCRC or the VRC laboratories [ Time Frame: Measured through Month 36 ] [ Designated as safety issue: No ]
  
• Cross-clade cellular immune responses to HIV-1 Gag-Pol-Nef peptides from clades A and C as assessed by IFN-γ ELISpot and ICS assays as performed by the FHCRC or the VRC laboratories [ Time Frame: Measured through Month 36 ] [ Designated as safety issue: No ]
  

The worldwide HIV/AIDS epidemic may only be controlled through development of a safe and effective vaccine that will prevent HIV infection. DNA vaccines are inexpensive to construct, readily produced in large quantities, and stable for long periods of time. This study will evaluate the safety and immunogenicity of an experimental multiclade HIV vaccine, VRC-HIVDNA016-00-VP, followed by a similarly structured adenovirus-vectored vaccine boost, VRC-HIVADV014-00-VP, in HIV uninfected adults. The DNA plasmids in both the vaccines code for proteins from HIV subtypes A, B, and C, which together represent 90% of new HIV infections in the world. Participants in this study will be recruited in North America, South America, and Africa.

Each volunteer will participate in the study for 36 months. Participants will be randomly assigned to one of two groups. Group 1 participants will receive the DNA HIV vaccine at study entry and at Months 1 and 2. At Month 6, Group 1 participants will receive an injection of the adenoviral vector HIV vaccine. Group 2 participants will receive placebo at study entry and Months 1, 2, and 6. There will be 17 study visits, which will occur at study entry and every 2 weeks thereafter until Day 70; at Month 6 and every 2 weeks thereafter until Day 210; and Months 9.5, 12, 18, 24, 30, and 36. A physical exam, adverse events reporting, HIV and pregnancy prevention counseling, and medication history will occur at each visit. Blood and urine collection will occur at selected visits.