Monitoring and modelling of a continuous from-powder-to-tablet process line

The intention to shift from batch to continuous production processes within the pharmaceutical industry enhances the need to monitor and control the process in-line and real-time to continuously guarantee the end-product quality. Mass and energy balances have been successfully applied to a drying process which is part of a continuous from-powder-to-tablet manufacturing line to calculate the residual moisture content of granules leaving the drying unit on the basis of continuously generated data from univariate sensors. Next to monitoring, the application of continuous processes demands also real-time adjustment of critical input variables to ensure that the process stays within the Design Space. Mechanistic models are very useful for this purpose as, once validated, several tools can be applied to gain further process knowledge, for example uncertainty and sensitivity analysis. In addition, several scenarios can be simulated, thus reducing the need to collect time-consuming, and often costly, experimental data.