Safety and Effectiveness of the Vaccine ALVAC-HIV vCP205 in HIV-Negative Adult Volunteers in Uganda

Overview

The purpose of this study is to see if it is safe to give ALVAC-HIV vCP205, a possible HIV vaccine, and to study the immune responses in adult HIV-1 uninfected volunteers. Uganda has been severely affected by HIV infection and AIDS and has been selected to participate in HIV-vaccine development. The HIV viruses commonly isolated from Uganda are 2 kinds that are not used in making current vaccines. Current vaccines generate several kinds of immune responses. Researchers would like to see if a response to the kind of virus in a current vaccine will also protect people from the viruses commonly found in Uganda.

The African country of Uganda is severely affected by HIV infection and AIDS and has been selected by the World Health Organization to participate in HIV-vaccine development. The predominant HIV-1 strains isolated from Ugandans are members of clade A and clade D. The only vaccines available for human testing are based on envelope proteins from clade B and clade E viruses. ALVAC-HIV vCP205 is a second generation vaccine that can induce a humoral and cellular response against several antigens. The current study will attempt to extend these findings to determine if the vCP205 vaccine, when administered to Ugandans, can induce cytotoxic T-lymphocyte (CTL) responses that are reactive against the HIV strains prevalent in Uganda. Volunteers are randomized into 1 of 3 groups and receive either the candidate HIV-1 vaccine ALVAC-HIV vCP205, the experimental canarypox rabies vaccine ALVAC-RG, or placebo-ALVAC. Neither the volunteer nor his/her health care professional knows which preparation is being given. Volunteers receive 4 injections over a period of 6 months and are followed for up to 24 months. Clinical observations and monitoring of hematological, chemical, and immunologic parameters are done. Safety is evaluated by monitoring for local and systemic adverse reactions during the course of the trial. Comparative immunogenicity analyses are based on CTL responses to HIV and measures of binding and HIV-specific antibody responses. At each visit, volunteers are counseled on how to avoid HIV exposure and pregnancy.