Study of an HIV Preventive Vaccine Given With or Without an Adjuvant in HIV Uninfected Adults

The HIV epidemic is a major global health challenge, causing tremendous human suffering and economic loss throughout the world. The need for a safe, effective, and affordable HIV preventive vaccine is critical. This study will determine the safety and immunogenicity of an experimental HIV vaccine, HIV-1 gag DNA, given with or without an IL-12 adjuvant and boosted HIV-1 gag DNA with or without IL-12 DNA adjuvant. This study will comprise two parts (Parts A and B). Part A will last 9 months and Part B, 15 months. Part A will consist of 48 participants enrolled in 4 groups. Group 1 participants will be randomly assigned to receive the gag DNA vaccine or placebo. Participants in Groups 2, 3, and 4 will be randomly assigned to receive the gag DNA vaccine and either 100 mcg, 500 mcg, or 1,500 mcg IL-12 DNA or placebo. Vaccinations for Groups 1 through 4 will be given intramuscularly and will occur at study entry and at Months 1 and 3. Part B will consist of 96 participants, enrolled in 3 groups. Participants in Part B will receive their first vaccination 2 weeks after Part A participants receive their second vaccination. Group 5 participants will receive either the HIV-1 gag DNA vaccine or placebo. Group 6 participants will receive either the HIV-1 gag DNA vaccine plus IL-12 DNA or placebo. Vaccinations for Groups 5 and 6 will occur at study entry and at Months 1, 3, 6, and 9. Group 7 participants will receive either the gag DNA vaccine plus IL-12 DNA or placebo at study entry and at Months 1 and 3. Throughout the study, blood and urine collections will occur, physical exams will be conducted, HIV testing and counseling will be offered, and interviews and questionnaires will be completed.