HIV-1 recombinant gp160 vaccine given in accelerated dose schedules

SUMMARY The purpose of this randomized, double-blind study was to test the safely and immunogenicity of an HIV-ILAI recombinant gp160 (rgp160) vaccine in healthy, uninfected volunteers using accelerated dosing schedules. Thirty volunteers were randomly assigned lo receive 50μg doses of rgp160 in one of two immunization schedules. Group 1 received rgp160 at times 0, 1, 2 and 5 months: and group 2 received rgp160 at times 0, 1, 2, 3 and 4 months. The vaccine was safe and stimulated high levels of HIV-1 envelope-specific binding antibody and T cell memory. There was a trend (P < 0.10) suggesting neutralizing antibodies were better induced by the regimen incorporating a rest period before the final immunization in group 1 volunteers. Both accelerated immunization schedules induced immune responses at levels similar to or better than those achieved by four rgp160 vaccine injections given over 12-18 months in other studies.