A phase II study of two HIV type 1 envelope vaccines, comparing their immunogenicity in populations at risk for acquiring HIV type 1 infection. AIDS Vaccine Evaluation Group.

Publication Type
Journal Article
Year of Publication
McElrath, M J; Corey, L; Montefiori, D; Wolff, M; Schwartz, D; Keefer, M; Belshe, R; Graham, B S; Matthews, T; Wright, P; Gorse, G; Dolin, R; Berman, P; Francis, D; Duliege, A M; Bolognesi, D; Stablein, D; Ketter, N; Fast, P
AIDS Res Hum Retroviruses
Date Published
2000 Jun 10
Adolescent; Adult; AIDS Vaccines; Amino Acid Sequence; Double-Blind Method; Female; HIV Antibodies; HIV Antigens; HIV Envelope Protein gp120; HIV Infections; HIV-1; Humans; Hypersensitivity, Delayed; In Vitro Techniques; Lymphocyte Activation; Male; Middle Aged; Molecular Sequence Data; Neutralization Tests; Peptide Fragments; Risk-Taking; safety; Time Factors

Several immunogens induce HIV-specific neutralization and in vitro lymphoproliferation in adults at low HIV-1 risk, but responses in persons at high HIV-1 risk are not known. We performed a multicenter, double-blinded, adjuvant-controlled trial with two gp120 vaccines in 296 HIV-1-uninfected volunteers, including 176 reporting higher HIV-1 risk activities. The immunogens were remarkably well tolerated. After three immunizations, 210 of 241 vaccinees (87%) developed neutralizing antibodies, which persisted in 59% after 2 years. The injection drug users receiving SF-2/gp120 had decreased antibody responses relative to the lower risk groups. Envelope-specific lymphoproliferation peaked after two immunizations, and 54% of vaccinees mounted a DTH reaction to gp120 after 4 years. In summary, these immunogens have low adverse reactogenicity and induce durable antibody and T cell responses to the prototype strains. Unexpected differences in antibody responses among diverse HIV-1 risk strata lend support to the conduct of expanded phase II trials in populations other than low-risk volunteers.