Speaker
Description
Infectious diseases play a substantial role in global public health concerns, and the evaluation of interventions aimed at reducing the burden of infection, such as vaccination, need rigorous studies to
assess their effectiveness and efficiency. Measuring antibodies is a possibility to quantify the impact of a vaccination, and the modelling of antibody kinetics, i.e. the change of antibody titer over time, is
crucial in optimizing the design of immunization trials. This includes determining the required sample size and optimal time points for antibody measurements/sampling in order to describe their kinetic
patterns accurately. We are currently conducting a systematic review, with the main objectives of identifying studies that use mathematical or statistical models to describe antibody kinetics and to determine in which context and how they have been used in the process of study design. A range of mathematical and statistical models are employed to account for the typically longitudinal structure of the data in immunization trials. These models include fundamental statistical approaches, such as linear models, or more sophisticated statistical techniques like nonlinear mixed effects models. Mathematical models are also frequently used, mostly in the form of deterministic within-host compartmental models, with varying levels of complexity. Despite the relatively high number of included publications (270), hardly any
considered models for study design.
In our research we try to answer the question of when and how often to measure antibody titer, to optimize the estimation of parameters used to model antibody kinetics. The sampling frequency depends on the number of parameters in the respective model, while promising approaches to determine the optimal sampling schedule utilize characteristics of the Fischer information matrix. For example, one of the most commonly used optimality criteria, D-optimality, finds the sampling schedule, which maximizes the determinant of the Fischer information matrix.
The limited use of mathematical models describing antibody kinetics, especially regarding study design, highlights the need and importance of basic research. Through our work, we aim to provide a framework, which can be actively used in practice to improve infectious disease study design.
