Active Immunization of HIV-Infected Pregnant Women: A Phase I Study of Safety and Immunogenicity of a rgp120/HIV-1 Vaccine (NOTE: Some Patients Receive Placebo)

PRIMARY: To evaluate the short-term safety of rgp120/HIV-1SF2 vaccine versus MF59 placebo administered to HIV-infected pregnant women. SECONDARY: To evaluate the immunogenicity and long-term safety of rgp120/HIV-1SF2 in HIV-infected pregnant women who received the vaccine during pregnancy only or during pregnancy and postpartum. To evaluate immunogenicity and safety in the infant through 18 months of age following maternal immunization with the vaccine during pregnancy. Active immunization of HIV-infected women during pregnancy may slow the progression of maternal disease, reduce the titer of virus in maternal plasma, and increase the titer of epitope-specific antibody. Also, active immunization has the potential to induce primary immunity in the fetus and to boost both T-cell and humoral immune responses to HIV in the mothers. Active immunization of HIV-infected women during pregnancy may slow the progression of maternal disease, reduce the titer of virus in maternal plasma, and increase the titer of epitope-specific antibody. Also, active immunization has the potential to induce primary immunity in the fetus and to boost both T-cell and humoral immune responses to HIV in the mothers. Women are randomized to receive rgp120/HIV-1SF2 vaccine or MF59 placebo. Patients receive the first immunization between 16 and 24 weeks gestation and monthly thereafter until delivery, for a maximum of five immunizations. Patients may continue to receive the immunization regimen to which they were originally assigned at 3, 6, 9, and 12 months postpartum. Maternal follow-up continues until 18 months postpartum; infants are followed until age 18 months.