INTRODUCTION: The estimation of herpes zoster (HZ) vaccine efficacy by time since vaccination and age at vaccination is crucial to assess the effectiveness and cost-effectiveness of HZ vaccination. Published estimates for the duration of protection from the vaccine diverge substantially, although based on data from the same trial for a follow-up period of 5 years. Different models were used to obtain these estimates, but it is unclear which of these models is most appropriate (if any). Only one study estimated vaccine efficacy by age at vaccination and time since vaccination combined. Recently, data became available from the same trial for a follow-up period of 7 years. AIM AND METHODS: We aim to elaborate on estimating HZ vaccine efficacy (1) by estimating it as a function of time since vaccination and age at vaccination, (2) by comparing the fits of a range of models, and (3) by fitting these models on data for a follow-up period of 5 and 7 years. RESULTS: Although the models' fit to data are very comparable, they differ substantially in how they estimate vaccine efficacy to change as a function of time since vaccination and age at vaccination. DISCUSSION: An accurate estimation of HZ vaccine efficacy by time since vaccination and age at vaccination is hampered by the lack of insight in the biological processes underlying HZ vaccine protection, and by the fact that such data are currently not available in sufficient detail. Uncertainty about the choice of model to estimate this important parameter should be acknowledged in cost-effectiveness analyses.
INTRODUCTION: The estimation of herpes zoster (HZ) vaccine efficacy by time since vaccination and age at vaccination is crucial to assess the effectiveness and cost-effectiveness of HZ vaccination. Published estimates for the duration of protection from the vaccine diverge substantially, although based on data from the same trial for a follow-up period of 5 years. Different models were used to obtain these estimates, but it is unclear which of these models is most appropriate (if any). Only one study estimated vaccine efficacy by age at vaccination and time since vaccination combined. Recently, data became available from the same trial for a follow-up period of 7 years. AIM AND METHODS: We aim to elaborate on estimating HZ vaccine efficacy (1) by estimating it as a function of time since vaccination and age at vaccination, (2) by comparing the fits of a range of models, and (3) by fitting these models on data for a follow-up period of 5 and 7 years. RESULTS: Although the models' fit to data are very comparable, they differ substantially in how they estimate vaccine efficacy to change as a function of time since vaccination and age at vaccination. DISCUSSION: An accurate estimation of HZ vaccine efficacy by time since vaccination and age at vaccination is hampered by the lack of insight in the biological processes underlying HZ vaccine protection, and by the fact that such data are currently not available in sufficient detail. Uncertainty about the choice of model to estimate this important parameter should be acknowledged in cost-effectiveness analyses.
Authors: Johannes Horn; André Karch; Oliver Damm; Mirjam E Kretzschmar; Anette Siedler; Bernhard Ultsch; Felix Weidemann; Ole Wichmann; Hartmut Hengel; Wolfgang Greiner; Rafael T Mikolajczyk Journal: Hum Vaccin Immunother Date: 2016-02-02 Impact factor: 3.452
Authors: Bernhard Ultsch; Felix Weidemann; Thomas Reinhold; Anette Siedler; Gérard Krause; Ole Wichmann Journal: BMC Health Serv Res Date: 2013-09-26 Impact factor: 2.655
Authors: Mélanie Drolet; Michael N Oxman; Myron J Levin; Kenneth E Schmader; Robert W Johnson; David Patrick; James A Mansi; Marc Brisson Journal: Hum Vaccin Immunother Date: 2013-01-16 Impact factor: 3.452