PAT applications extract real time data from a process by employing fast and (mostly) non-invasive spectroscopic and optical technologies and translate recorded raw data into meaningful process information in order to control the process in real time. In a traditional (non PAT) approach process performance can only be assessed via the quality of the end product. Adequate performance of the process can therefore only be judged retrospectively, when the end product already may have to be rejected.
Besides process control, PAT data can be used efficiently to increase process understanding during development, validation, transfer or routine manufacturing. PAT data can be seen as a process signature allowing for in-depth interpretation, mechanistic understanding and continuous improvement of your process.
A third possibility is to employ PAT as a substitute for traditional release testing, known as Real Time Release. This approach saves laborious analytical testing and logistical efforts and shortens the cycle time of manufacturing significantly. Besides direct benefits from a process quality en performance perspective, health agencies like FDA strongly encourage the use of PAT and available technologies to improve process understanding and performance:
Conventional pharmaceutical manufacturing is generally accomplished using batch processing with laboratory testing conducted on collected samples to evaluate quality. This conventional approach has been successful in providing quality pharmaceuticals to the public. However, today significant opportunities exist for improving pharmaceutical development, manufacturing, and quality assurance through innovation in product and process development, process analysis, and process control.
[ref. Guidance for industry: PAT, FDA sep 2004]