A Phase I Clinical Trial to Evaluate the Safety and Immunogenicity of the HIV-1 DNA Vaccine VRC-HIVDNA009-00-VP (Gag-Pol-Nef-multiclade Env) With the Plasmid Cytokine Adjuvant VRC-ADJDNA004-IL2-VP (IL-2/Ig)

Over 90% of the 40 million people infected with HIV live in developing countries and have little or no access to antiretroviral medications. The worldwide HIV/AIDS epidemic will 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. The DNA vaccine in this study, VRC-HIVDNA009-00-VP (Gag-Pol-Nef-multiclade Env), uses multiple gene products to increase the breadth of the immune response across different HIV subtypes. The DNA plasmids in VRC-HIVDNA009-00-VP code for proteins from HIV subtypes A, B, and C, which together represent 90% of new HIV infections in the world.

The study vaccine is administered with an adjuvant. The adjuvant is a DNA plasmid encoding interleukin 2 (IL-2) fused to the Fc portion of IgG for enhanced stability. This IL-2/Ig adjuvant may augment the immune system's response to the vaccine.

Participants in this study will be randomly assigned to receive either the vaccine and adjuvant, the vaccine and placebo, the adjuvant and placebo, or placebo alone. All injections will be administered by needle-free injection in the upper arm. Participants will receive four does of vaccine: one at their first study visit and then at Months 1, 2, and 6. Participants will have a follow-up visit 2 days after each injection. Some participants may receive another injection at this follow-up visit. All study participants will be followed for 18 months and will have 16 to 20 study visits. Study visits will last 1/2 to 2 hours and will include blood and urine tests and a physical exam. Participants will also have six HIV tests over the course of the study.