Effect of therapeutic immunization with HIV type 1 recombinant glycoprotein 160 ImmunoAG vaccine in HIV-infected individuals with CD4(+) T cell counts of <= 500 and 200-400/mm(3) (AIDS Clinical Trials Group study 246/946)

AIDS Clinical Trials Group (ACTG) 246/946 was a double-blinded, randomized, controlled trial of HIV-1 MN rgp160 ImmunoAG vaccine in HIV-infected patie nts with CD4(+) T cell counts greater than or equal to 500 and 200-400/mm(3 ). The main objectives were to study the safety and immunogenicity of this vaccine and to study the persistence of the immune responses after vaccinat ion over a longer period of time. Fifteen patients with CD4(+) T cell count s of greater than or equal to 500/mm(3) were enrolled in the ACTG 246 study . ACTG 246 patients received a monthly injection of vaccine or control for 6 months and then injections every 2 months. After completion of this study , seven new patients with CD4(+) T cell counts of 200-400/mm(3) entered int o the ACTG 946 study. These study patients received highly active antiretro viral therapy (HAART) (ritonavir, didanosine, and stavudine) for 9 weeks to stabilize their viral load and then each patient received a monthly inject ion of vaccine or control substance for 6 months with HAART. The study of t hese two relatively small populations showed that the vaccine was safe with out any adverse effect both in the patients with CD4(+) T cell counts of gr eater than or equal to 500 and 200-400/mm(3). The vaccine was also immunoge nic in patients with CD4(+) T cell counts of greater than or equal to 500/m m(3) as measured by gp160-specific lymphocyte proliferative responses, and it persisted after they had received more than six vaccine injections, for a longer period of time.