PHASE-I CLINICAL-TRIAL WITH A HEXAVALENT PORA CONTAINING MENINGOCOCCAL OUTER-MEMBRANE VESICLE VACCINE

A meningococcal outer membrane vesicle (OMY) vaccine was prepared from two production strains designed to express three serosubtype-specific class I outer membrane proteins or PorA. The resulting hexavalent Por A OMV vaccine contained the serosubtypes P1.7,16; P1.5,2; P1.19,15; P1 .7(h),4; P1.5(c),10; P1.12,13 and were used to immunize adult voluntee rs. A single immunization with two dosages, 7.5 and 15 mu g of the ind ividual PorAs, was studied. The vaccine was considered safe for furthe r use. Approximately half of the volunteers demonstrated a fourfold in crease in bactericidal antibody activity against six test strains expr essing the specific PorAs when given the higher dosage. This bacterici dal activity was found to be directed against PorA. Copyright (C) 1996 Elsevier Science Ltd.