This study will evaluate the safety, tolerability, and immune response to two different vaccine schedules of a prime with either DNA HIV vaccine (DNA-HIV-PT123), or NYVAC HIV vaccine (NYVAC-HIV-PT1 and NYVAC-HIV-PT4) followed by a boost combination of NYVAC HIV vaccine (PT1 & PT4) and AIDSVAX B/E. Study researchers will also evaluate whether body mass index (BMI) and/or sex impact the immunogenicity of the vaccine regimens in participants from South Africa, and look at regional differences in immunologic responses between United States and South African participants.~The study will enroll 264 healthy, HIV-uninfected people, ages 18-50, in the United States and South Africa.~Participants will be randomly assigned to one of three groups and receive either one of the vaccine regimens or placebo. Participants will receive injections according to their assigned group schedule at study entry (Month 0) and Months 1, 3, and 6.~Participants will remain in the clinic for 30 minutes after receiving the vaccines for observation and monitoring. For 7 days after receiving the vaccines, participants will record their symptoms and report them to study researchers.~Study visits will occur at study entry, and Months 1, 1.5, 3, 3.5, 6, 6.5, 9, and 12. All study visits will include a physical examination, HIV risk reduction counseling, and interviews and/or questionnaires. Select study visits will include urine collection, an electrocardiogram (ECG), blood collection, a pregnancy test for female participants, and HIV testing. At some visits, some participants may also provide samples of cervical fluid, rectal fluid, and/or semen. Study researchers will contact participants by telephone or e-mail once a year for 3 years following the first vaccination for follow-up health monitoring.
The purpose of this study is to evaluate the safety and immune response to two different HIV vaccine regimens in healthy, HIV-uninfected people in the United States and South Africa.