A process analytical technology (Pat) approach to evaluate gabapentin distribution in laminar extrudates

Abstract

The work combines the use of fast and non-destructive analytical techniques for rapid on-line process monitoring and evaluation of the drug product quality, within the Process Analytical Technology strategy recommended by regulatory authorities, applied to laminar extrudates designed to deliver gabapentin orally. Laminar extrusion is a promising technology to deliver drugs in different polymorphic forms by different release kinetics. The work focuses on accessing the homogeneity of gabapentin’s (GABA) distribution in laminar extrudates by Raman and Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopies as PAT tools. In the framework of the project, the evaluation of formulation and process factors impacting on gabapentin polymorphic form was also carried out by differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD). It has been observed that the addition of water during manufacturing process of extrudates was a critical formulation factor that might had promoted the conversion of crystalline gabapentin into its amorphous form. Raman imaging indicated that gabapentin was distributed homogeneously in the investigated laminar extrudates without the detection of agglomerates in the Raman map. The results of XRPD, DSC and ATR-FTIR analysis confirmed that gabapentin was present as the amorphous form of the drug in the laminar extrudates.