AEGiS-11IAC: Clinical and immunological aspects of HIV-infected patients in double blind trial with VaxSyn (Registered) (rgp160) and AZT or related placebo.

11th International AIDS Conference

Vancouver, British Columbia — July 7-12, 1996

Clinical and immunological aspects of HIV-infected patients in double blind trial with VaxSyn (Registered) (rgp160) and AZT or related placebo.

Int Conf AIDS 1996 Jul 7-12; 11:221 (abstract no. Th.B.177)
Guerra EC, Pontesilli O, Mezzaroma I, Varani AR, Carlesimo M, Ricci G, Pinter E, Scala E, Antinori A, Ammassari A, De Luca A, Murri R, Visconti E, Vella S, Ortona L, Aiuti F; Catteora Di Allergologia E Immunologia Clinica, Viale Dell Universita, Roma, Italy. Fax: +39+6+4463328.

OBJECTIVE: To evaluate the effects of rgp 160 (VaxSyn(Registered), MicrogeneSys Inc. Meridien CT, USA) immunotherapy associated or not with AZT on safety and immuno- virological markers, in asymptomatic HIV- infected patients with CD4 counts greater than 400 and less than 600 cells/mmc.

METHODS: Ninety-nine patients were enrolled between February 3rd 1993 and November 13th 1993. The patients were randomized into 3 treatment groups 1) Placebo VaxSyn (Registered) (Alume)+ AZT, 2) VaxSyn (Registered) + Placebo AZT, 3) VaxSyn (Registered) + AZT. Immunological response, viral load, clinical evolution of disease, adverse events and reactogenicity were monitored at every administration.

RESULTS: On December 30th 1995, 68 of the 99 enrolled patients were still included in the study. Regarding thirthy-one patients who dropped out, 16 left voluntarily the study. Two patients dropped out owing to pregnancy. Twelve patients reached the endpoint of the clinical progression of the disease (One of these patients died on April 18th 1995 due to thrombotic thrombocytopenic purpura). Another patient active in the study died of cerebral haemorrhage on August 15th 1995. In the first 24 months of treatment circulating CD4+ lymphocytes of all enrolled patients were substantially mantained with an average, not significant tendency to increase compared to the time of enrollment. A statistic tendency to increase was found in CD3+CD8+ lymphocytes (p=0,0007). No significant modifications were found in CD4+CD45RA+ and CD4+CD45RO+ lymphocytes. Lymphoproliferative responses to the immunizing antigen (rgp160) were studied in 60 enrolled subjects; before starting the treatment 11.6% showed a significant response to gp 160. The percentage of patients with significant lymphoproliferation to rgp 160 reached 72.73%. Env-specific cytotoxicity was studied in 35 patients; before starting the treatment 28% showed a significant response to Env. During the trial an Env-cytotoxicity was observed in more than 40% of enrolled patients. No decline was observed during the trial. Other immunological parameters were studied. Preliminary HIV-RNA data in 17 out of 46 patients showed a reduction of at least 0.5 Log of RNA from Day 1 to Day 30. The CD4+ average of this group in the same period increased from 491/mm3 to 523/mm3.

CONCLUSIONS: The results of 24 months follow-up indicate that the association of VaxSyn (Registered) + AZT is generally well tolerated. Unblinded analysis of laboratory data and long term follow-up of the patients are needed to assess treatment efficacy.

Keywords: AEGIS, Zidovudine, AIDS Vaccines, HIV, Double-Blind Method, Placebos, Viral Load, HIV Infections, HIV Envelope Protein gp160, CD4-Positive T-Lymphocytes, Anti-HIV Agents, Single-Blind Method, HIV Core Protein p24, CD8-Positive T-Lymphocytes, HIV Seropositivity, HIV Envelope Protein gp120, Reverse Transcriptase Inhibitors, HIV Antigens, VaxSyn HIV-1 (gp160) vaccine, Human, Female, Pregnancy, immunology, ICA11

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ThB177