Innovative approaches to consider include, but are not limited to: (a) Process Analytical Technology (PAT) real-time monitoring and feedforward controlling of the powder blending process1 and (b) use of Statistical Process Control (SPC) tools to monitor the powder blending process and to maintain a state of control.
When a manufacturer decides to implement PAT or other process-monitoring and control techniques for powder blend homogeneity assessment, its decision should be supported with appropriate data and rationale using a science- and risk-based approach. For example, the effective sample size of powder examined by PAT probes has to be estimated, such that the scale of scrutiny of the PAT powder blending monitoring can be justified.2 The number of PAT probes and their locations also have to be justified. If a scientifically sound PAT monitoring and control strategy is established, it can facilitate the assessment of: (a) variability across locations within the powder bed,3 (b) the variability over time of one location, and (c) the potential correlation between the powder sample and the unit dosage form.
