A Trial to Evaluate Ad35-GRIN/ENV HIV Vaccine in Healthy Adult Volunteers

This study is a phase I dose-escalation randomized, placebo-controlled study designed to evaluate the safety and immunogenicity of Ad35-GRIN and Ad35-ENV filled in the same vial and administered as a single, combined vaccine. This is the first administration of this vaccine in humans. The study will be double blind with respect to vaccine or placebo. The vaccine will be administered intramuscularly at months 0 and 6 at three dose levels: 2 x 10\^9, 2 x 10\^10, and 2 x 10\^11 vp per dose. Volunteers will be randomized to vaccine: placebo in a 10:4 ratio in each group. A fourth group was added as a protocol amendment to study Ad35-GRIN HIV vaccine alone at 1x10\^10 vp in 14 volunteers (10:4 vaccine:placebo). Volunteers will be screened up to 42 days before vaccination (90 days for Ad35 neutralizing antibody screening) and will be followed for 12 months after the last vaccination (18 months total study participation). Estimated enrollment will take approximately 5 months. Thus, the total duration of the study would be approximately 23 months.