J Acquir Immune Defic Syndr. 2002 Mar 1; 29(3):254-261.

PubMed ID: 11873074

Safety and immunogenicity of a high-titered canarypox vaccine in combination with rgp120 in a diverse population of HIV-1-uninfected adults: AIDS Vaccine Evaluation Group Protocol 022A

Gupta K, Hudgens M, Corey L, McElrath MJ, Weinhold K, Montefiori DC, Gorse GJ, Frey SE, Keefer MC, Evans TG, Dolin R, Schwartz DH, Harro C, Graham B, Spearman PW, Mulligan M, Goepfert P; AIDS Vaccine Evaluation Group

To test the safety and immunogenicity of a high-titered preparation of ALVAC-HIV vCP205 in both high-risk and low-risk persons and to evaluate variations in dosing schedule, we conducted a multicenter, randomized, double-blind trial of this vector in combination with recombinant subunit gp120 in 150 HIV-1-seronegative volunteers. The high-titered ALVAC vaccine was well tolerated; adverse events were minimal and not influenced by dosing. At day 728, the cumulative probability of a cytotoxic T-lymphocyte (CTL) response was 76% (95% confidence interval [CI]: 64%-89%) among volunteers receiving vaccine, and the net amount attributable to vaccination was 50% (CI: 16%; 74%). The net probability of a repeated positive CTL response by day 728 was 50% (CI: 21%; 64%). There was a significant difference in CTL response at day 182 between volunteers who had received four doses versus three doses of vCP205 (42% vs. 24%, p =.052). The CTL response was similar in high-risk volunteers and vaccinia-naive volunteers compared with vaccinia-immune volunteers. Neutralizing antibody responses were detected in 95% of vaccinees at day 287, with higher geometric mean titers in recipients of sequential versus simultaneous dosing of the two vaccines and in vaccinia-naive volunteers. This high-titered preparation of ALVAC-HIV vCP205 in combination with gp120 was safe and immunogenic in a diverse group of HIV-1-seronegative volunteers.