HVTN Protocol 204 - A Phase II Clinical Trial to Evaluate the Safety and Immunogenicity of a Multiclade HIV-1 DNA Plasmid Vaccine, VRC-HIVDNA016-00-VP, Followed by a Multiclade Recombinant Adenoviral Vector HIV-1 Vaccine Boost, VRCHIVADV014-00-VP, in HIV-1 Uninfected Adult Participants

The purpose of the study is to determine the safety of and immune response to a DNA HIV vaccine followed by an adenoviral vector HIV vaccine in HIV uninfected adults.

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.