The aim of this study is to show the robustness of a commercial direct compression system running continuously under relevant process conditions for over 120 h. The study will apply a representative commercial control strategy including real time monitoring of process parameters, rejection of OOS material, use of in-line NIR prediction for blend potency monitoring, application of mathematical RTD modelling for real-time prediction of product potency, and tablet concentration prediction by tablet NIR. The study showed that the process can produce in specification product robustly over significant operating times. Across 122 h of actual run time (including pauses) the process manufactured over 15 million tablets to give a product yield of 99.2%. Whilst the purpose of this study was to evaluate the process for over 120 h, this process is not limited to running longer periods of time given the performance of the equipment and the control strategy. (C) 2020 Published by Elsevier B.V.