Gelation Film Coatings Applied to Mini-Tablets for Bitterness Masking and Improved Swallowability

Gelation film-coating (GFC) technology has attracted attention as a strategy to improve the swallowability and taste masking of oral solid dosage forms; however, its application to mini-tablets remains challenging because of their high specific surface area and manufacturing limitations. This study aimed to develop a simple and scalable GFC formulation for mini-tablets using standard film-coating equipment. A poly(vinyl alcohol)/polyethylene glycol graft copolymer (PVAPEG) was used as the base polymer, and various thickening agents were screened to optimize the gel formation, disintegration behavior, and surface adhesion. The formulations were evaluated in terms of maximum extrusion stress, disintegration time, dissolution performance, pharmacokinetics, sensory characteristics, and stability. Among the tested formulations, xanthan gum (XG) provided an optimal balance between reduced adhesion and controlled disintegration. GFC mini-tablets containing PVAPEG and XG significantly improved swallowability and bitterness masking compared to uncoated formulations, while maintaining rapid drug dissolution comparable to that of the reference product. Bioequivalence with the marketed product was confirmed, and accelerated stability studies demonstrated excellent stability of the formulation. These findings indicate that GFC mini-tablets based on PVAPEG and XG represent a robust and scalable formulation strategy that enhances patient acceptability without compromising the pharmaceutical performance.