Phase II study of anti-CD4 idiotype vaccination in HIV positive volunteers

A clinical phase II trial of postinfectional idiotype vaccination was performed in early stage HIV+ volunteers. The mAb 13B8.2 is directed against the CDR3-homologous CD4/D1 region implicated in HIV-gp120 binding. We have previously shown that this mAb induces HIV-gp120 cross-reactive immunity. In addition, the mAb 13B8.2 was well tolerated in a clinical phase-Ia trial. In this phase-II trial, 158 patients with 350-500 CD4+ cells/mu l blood were randomised to receive either 1.2 mg of alumprecipitated mAb 13B8.2 or placebo, The mAb was well tolerated evoking predominantly local side effects. Multivariant analysis of clinical study endpoints demonstrated a significant response in the verum group (intend-lo-treat analysis). Titres of HIV-1 neutralisation in vitro were raised along with HIV/gp120 antigen binding titres. Our data indicate that patients treated with the idiotype vaccine will produce an augmented specific anti-viral immune response. The vaccine might thus have a positive impact on the course of HIV disease. (C) 1999 Elsevier Science Ltd. All rights reserved.