Safety and Immunogenicity of a Canarypox-Vectored Human Immunodeficiency Virus Type 1 Vaccine with or without gp120: A Phase 2 Study in Higher- and Lower-Risk Volunteers

• Published in: The Journal of infectious diseases 2001-05, Vol.183 (9), p.1343-1352
• Main Authors: Belshe, Robert B., Stevens, Cladd, Gorse, Geoffrey J., Buchbinder, Susan, Weinhold, Kent, Sheppard, Haynes, Stablein, Donald, Self, Steve, McNamara, James, Frey, Sharon, Flores, Jorge, Excler, Jean Louis, Klein, Michel, El Habib, Raphaelle, Duliege, Anne-Marie, Harro, Clayton, Corey, Lawrence, Keefer, Michael, Mulligan, Mark, Wright, Peter, Celum, Connie, Judson, Frank, Mayer, Kenneth, McKirnan, David, Marmor, Michael
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; AIDS Vaccines - genetics; AIDS Vaccines - immunology; Antibodies; Antigens; Avipoxvirus - immunology; Biological and medical sciences; canarypox virus; CD8-Positive T-Lymphocytes - immunology; Double-Blind Method; Experimentation; Female; Fundamental and applied biological sciences. Psychology; Genetic Vectors; glycoprotein gp120; HIV; HIV 1; HIV Envelope Protein gp120 - genetics; HIV Envelope Protein gp120 - immunology; HIV infections; HIV Infections - prevention & control; HIV Protease - genetics; HIV Protease - immunology; HIV-1 - immunology; Human experimentation; human immunodeficiency virus; Human immunodeficiency virus 1; Human viral diseases; Humans; Immunization Schedule; Immunization, Secondary; Infectious diseases; Major Articles; Male; Medical sciences; Microbiology; Middle Aged; p55 protein; Placebos; Risk Factors; Safety; T-Lymphocytes, Cytotoxic - immunology; Vaccination; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies; Vaccines, Attenuated; Vaccines, Synthetic; Viral diseases; Viral diseases of the lymphoid tissue and the blood. Aids; Virology; Volunteerism
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/319863

Live attenuated viral vectors that express human immunodeficiency virus (HIV) antigens are being developed as potential vaccines to prevent HIV infection. The first phase 2 trial with a canarypox vector (vCP205, which expresses gp120, p55, and protease) was conducted in 435 volunteers with and without gp120 boosting, to expand the safety database and to compare the immunogenicity of the vector in volunteers who were at higher risk with that in volunteers at lower risk for HIV infection. Neutralizing antibodies to the MN strain were stimulated in 94% of volunteers given vCP205 plus gp120 and in 56% of volunteers given vCP205 alone. CD8+ cytotoxic T lymphocyte cells developed at some time point in 33% of volunteers given vCP205, with or without gp120. Phase 3 field trials with these or similar vaccines are needed, to determine whether efficacy in preventing HIV infection or in slowing disease progression among vaccinees who become infected is associated with the level and types of immune responses that were induced by the vaccines in this study