A "Large-N" Content Uniformity Process Analytical Technology (PAT) Method for Phenytoin Sodium Tablets

Area of Science:

• Pharmaceutical Technology
• Analytical Chemistry
• Process Analytical Technology (PAT)

Background:

• Accurate content uniformity assessment is vital for narrow therapeutic index drugs like phenytoin sodium.
• Traditional analytical methods can be time-consuming for large-scale manufacturing.
• Process Analytical Technology (PAT) offers potential for real-time quality monitoring.

Purpose of the Study:

• To develop and validate a rapid near-infrared (NIR) spectroscopy method for predicting phenytoin sodium tablet content uniformity.
• To establish a robust calibration model using a partial least squares (PLS) approach.
• To demonstrate the method's applicability to pilot-scale manufactured tablets.

Main Methods:

• Generation of calibration tablets with varied formulation and process parameters.
• Acquisition of NIR spectra from individual tablets.
• Development of a PLS regression model correlating NIR spectra to tablet content.
• Validation using a modified United States Pharmacopeia (USP) HPLC assay method.
• Application of bootstrapping for statistical analysis of quality metrics.

Main Results:

• A PLS model with 4 latent variables explained 92% of composition variability.
• The model achieved a root mean square error of prediction (RMSEP) of 0.48% w/w.
• The NIR method accurately assayed pilot-scale manufactured phenytoin sodium tablets.
• Bootstrapping demonstrated that increased sample size narrowed confidence intervals for key quality metrics.

Conclusions:

• The developed NIR-based PAT method provides a rapid and reliable approach for assessing phenytoin sodium tablet content uniformity.
• This method can significantly enhance quality control and reduce analytical testing time in solid dosage manufacturing.
• The 'large N' approach improves the reliability of quality assessments, ensuring drug safety and efficacy.