Conditions: AIDS HIV Infections
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 3000
Healthy volunteers: yes

Brief summary:
This study will test the safety and efficacy of an investigational Human Immunodeficiency Virus (HIV) vaccine. Efficacy will be measured by either prevention of HIV infection or control of HIV viral load in subjects who become HIV infected.

On September 18, 2007 the Protocol V520-023 DSMB (Data \& Safety Monitoring Board) reviewed data from a planned interim analysis. These data demonstrated that the investigational vaccine candidate was not effective, and all vaccinations in the study were halted.

Participants were encouraged to continue to come to the clinic for scheduled visits and ongoing risk reduction counseling since the vaccine was not effective.

Detailed description:
No further treatment was given in V520-023, however participants were followed. V520-023 protocol ended earlier than originally planned per protocol and participants (HIV infected and uninfected) had the option of participating in an observational long term follow up protocol called V520-030/HVTN 504, which served as an extension of V520-023 and would continue through the end of 2009.

Arms:
arm 1: Participants randomized to receive three 1.0-ml intramuscular (IM) injections of Merck Trivalent Adenovirus Serotype 5 HIV-1 gag/pol/nef (MRKAd5 HIV-1 gag/pol/nef) Vaccine at a dose of 1.5x10\^10 adenovirus genomes (Ad vg) per dose at Day 1, Week 4, and Week 26. arm 2: Participants randomized to receive three 1.0-ml intramuscular (IM) injections of placebo to MRKAd5 HIV-1 gag/pol/nef at Day 1, Week 4, and Week 26.

Interventions: intervention 1: Trivalent MRKAd5 HIV-1 gag/pol/nef (1.5x10^10 ad-vg/dose) intervention 2: Comparator: placebo
Intervention descriptions: intervention 1: Trivalent MRKAd5 HIV-1 gag/pol/nef (1.5x10\^10 adenovirus genomes \[ad-vg\]/dose).

This dose is equivalent to 3x10\^10 vp/dose used in study V520-016. intervention 2: Placebo to Trivalent MRKAd5 HIV-1 gag/pol/nef in three 1 mL doses at Day 1, Week 4, and Week 26 administered intramuscularly.

Protocol document: