Active immunization of patients with HIV infection: A study of the effect of VaxSyn, a recombinant HIV envelope subunit vaccine, on progression of immunodeficiency

Infection with the human immunodeficiency virus (HIV) leads to a progressive immunodeficiency characterized by decreasing levels of CD4⁺ T lymphocytes. VaxSyn, a vaccine based on the recombinant envelope glycoprotein subunit (rgp160) of HIV-1(IIIB), was used to immunize HIV-infected patients to determine whether its administration was beneficial with respect to slowing disease progression. A 3-year multicenter, randomized, placebo- controlled, double-blinded, efficacy and safety trial of repeated immunization with VaxSyn was used to evaluate the long-term impact on the progression of immunodeficiency. VaxSyn in alum, or alum alone, was given to 278 HIV-infected asymptomatic individuals with initial CD4 counts of ≤500 cells/mm³. Clinical findings, the CD4 count, and both virological and immunological parameters were followed. No significant differences were observed between the treatment and placebo control groups in rate of CD4 T cell decline, time to initiation of antiretroviral therapy, incidence of opportunistic infections, HIV RNA plasma viremia, HIV viral infectivity as measured by quantitative HIV coculture assay, and death. This study revealed no effect on either clinical or laboratory virological parameters from the administration of VaxSyn.