PAT for monitoring the state of control in continuous manufacturing of solid oral dosage forms.

Process analytical technology plays an important role in maintaining the state of control during pharmaceutical manufacturing processes. This review discusses different studies where continuous manufacturing runs were monitored up to 120 h. This set of studies have used near infrared spectroscopy to determine the drug concentration and confirm whether the pharmaceutical products are within specifications. The performance of these methods was evaluated through validations that included accuracy, precision, linearity, and robustness tests. The importance of the repeatability study is emphasized in this review. Different sampling locations have been shown to be useful for real-time monitoring. Process analytical technology and residence time distribution models have enabled the detection of non-conforming material and its diversion from the manufacturing process. The use of variographic analysis for improving process analytical technology implementation is discussed, since it is the only method that differentiates process variability from sampling and analytical errors. The studies discussed in this review have contributed to the improvement of the continuous manufacturing processes, providing a high level of product and process understanding, product quality, and reliability.