Primary Outcome Measures:
- Safety of administering vCP205 vaccinations to healthy adult individuals [ Time Frame: Throughout study ] [ Designated as safety issue: Yes ]
Secondary Outcome Measures:
- Immunogenicity of SC vaccination with four doses of vCP205 administered in the groin area versus four doses administered IM in the deltoid region, as measured by CTL activity directed to canarypox and HIV-1 env, gag and pol gene products [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
- Immunogenicity of SC vaccination with four doses of vCP205 administered in the groin area versus four doses administered IM in the deltoid region, as measured by anti-HIV-1 directed CD4+ T cell proliferative response to soluble p24 antigen [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
- Immunogenicity of SC vaccination with four doses of vCP205 administered in the groin area versus four doses administered IM in the deltoid region, as measured by CD8+ T cell specificity for HIV-1 epitopes [ Time Frame: Throughout study ] [ Designated as safety issue: No ]
HIV is most commonly transmitted via a mucosal surface. The mucosal lining is a potential site of both humoral and cellular protection through the activity of B lymphocytes, activated memory T lymphocytes, secretory IgA, and antigen presenting cells. In addition to systemic immunity, a preventive HIV vaccine should induce immune responses at the mucosal surfaces that are portals of HIV entry into the body.
Targeted lymph node immunization involves vaccine injection into the subcutaneous tissue near a lymph node. This strategy has proven effective in the simian immunodeficiency virus (SIV)/rhesus macaque model. The iliac and inguinal lymph nodes in the groin are the primary draining lymph nodes of the genitourinary and rectal tracts. This study will evaluate and compare the safety and immunogenicity of ALVAC-HIV (vCP205) when administered subcutaneously in the groin and intramuscularly in the deltoid region. ALVAC-HIV (vCP205) is a canarypox virus vector vaccine expressing portions of the gp120, Gag, and Pol genes.
Participants in this study will be randomly assigned to receive vaccine or placebo injections in the groin area or the upper arm. All participants will have three baseline visits for blood tests and sigmoidoscopies to measure baseline immune functions. After these visits, participants will receive weekly injections for 4 weeks. Groin injections will be given subcutaneously (under the skin) and upper arm injections will be given intramuscularly (into the muscle). Participants will have follow-up visits 5 and 11 months after the last immunization. Participants will have blood draws and sigmoidoscopies and will receive HIV risk reduction counseling throughout the study. Total length of participation will be approximately 14 months. Participants may continue to contact the study for HIV testing and study-related concerns for 1 year after study participation.