Production planning of batch and semi-continuous bioprocesses across multiple biopharmaceutical facilities

Production planning for biopharmaceutical portfolios becomes more complex when products switch between fed-batch and continuous perfusion culture processes. This paper describes the development of a mixed integer linear programming (MILP) model that incorporates both perfusion and fed-batch processes to optimise capacity plans for multiple products across multiple facilities to meet quarterly demands. Specific constraints have been created to capture challenges dealing with processes with different modes of operation such as sequence-dependent changeover times. The model is applied to an industrial case study to illustrate how the framework aids decisions regarding outsourcing capacity to third party manufacturers or building new facilities. The impact of uncertainties on the optimal production plans and costs is captured through the use of scenario analysis.