Safety and immunogenicity of the modified adult tick-borne encephalitis vaccine FSME-IMMUN super([registered]): Results of two large phase 3 clinical studies

• Published in: Vaccine 2006-06, Vol.24 (24), p.5256-5263
• Main Authors: Loew-Baselli, A, Konior, R, Pavlova, B G, Fritsch, S, Poellabauer, E, Maritsch, F, Harmacek, P, Krammer, M, Barrett, P N, Ehrlich, HJ
• Format: Article
• Language: English
• Subjects: Tick-borne encephalitis virus
• ISSN: 0264-410X
• DOI: 10.1016/j.vaccine.2006.03.061

A prospective, randomised, multicentre, single-blind phase 3 study was performed to assess the safety of a vaccination schedule consisting of two vaccinations (21-35 days apart) with the tick-borne encephalitis (TBE) vaccine FSME-IMMUN super([registered]) "adults" (five consecutive lots) in comparison to another licensed TBE vaccine (Encepur super([registered]), with polygeline) (two lots) in healthy volunteers (n = 3966) aged 16-65 years. The safety of the third vaccination with FSME-IMMUN super([registered]) "adults" (6 months after the first vaccination) was investigated in a follow-up study on the same population (n = 3705) and TBE antibody titres were analysed pre- and post-vaccination in a subgroup of volunteers (n = 564). Following the first vaccination, the overall incidence of fever (>=38.0 degree C) was 0.8% in the FSME- IMMUN super([registered]) "adults" study group and 5.6% in the comparator study group; fever was mainly mild. The fever rate after the second vaccination was 0.6% and 0.5% in the two study groups, respectively. Local and systemic reactions after the first vaccination occurred with a lower frequency in the FSME-IMMUN super([registered]) "adults" study group than in the comparator group. Upon analysing the tolerability of the third vaccination with FSME- IMMUN super([registered]) "adults", similar results were determined in both study groups of volunteers previously vaccinated with FSME-IMMUN super([registered]) "adults" or with the comparator vaccine. The immunogenicity results demonstrated similar seroconversion rates (as determined by ELISA or neutralization test) before and after the third vaccination in the FSME-IMMUN super([registered]) "adults" group and in the comparator group respectively. The results of both studies demonstrate that: (1) FSME-IMMUN super([registered]) "adults" is safe and highly immunogenic, (2) all five production lots of FSME-IMMUN super([registered]) "adults" were consistent with respect to a low rate of adverse events, (3) FSME- IMMUN super([registered]) "adults" induces considerably lower adverse reaction rates than the comparator vaccine after the first vaccination, and (4) two vaccinations with the comparator vaccine can be successfully followed by a third vaccination with FSME-IMMUN super([registered]) "adults".