Robustness testing of live attenuated rubella vaccine potency assay using fractional factorial design of experiments

The potency assay for the freeze-dried live attenuated rubella vaccine is a cell culture based biological assay. The aim of our study was to perform the robustness testing of the rubella vaccine potency assay prior to validation. Seven intra-assay operating conditions that could have an effect on the assay performance were identified and their influence on the overall assay variability investigated by fractional factorial design of experiments (DoE). The robustness testing through DoE showed that the rubella vaccine potency assay is a robust assay. Critical operating conditions can be identified using DoE, which indicates that it is a suitable approach in bioassay robustness studies.