The evaluation of controlled release multiparticulate dosage forms prepared using a novel coating method

A novel solid dispersion, hot melt, fluid bed coating method has been reported in the literature. Previous work has established the utility of the method in applying polyethylene glycol to the surface of beads and tablets. Preliminary work was also completed by the same author indicating the method may be useful in the area of controlled release.;The current research focuses on the use of this novel method to create controlled release multiparticulate dosage forms. More than a dozen potential coating agents were screened to determine their usefulness in slowing the release of active agent from beaded substrate when applied with this method. Those materials that showed promise were selected for modification in an attempt to improve their release-controlling performance. Addition of the insoluble particle titanium dioxide slightly improved the performance of one of the coating agents. Release profiles were generated that met USP specifications for Chlorpheniramine Maleate Extended-release capsules. These profiles were statistically identical to those of the currently marketed product Teldrin.;The data from the batches prepared in this lab were modeled to determine their release kinetics. A dual equation, which combined first order release kinetics with square-root-of-time dependent kinetics, fit the data very well. This equation was able to describe the release data from these systems better than either the first order equation or the square-root-of-time equation alone. A release mechanism consistent with these observations was proposed.;It was concluded that the novel solid dispersion, hot melt, fluid bed coating is a viable means by which to apply select lipophilic coating agents to retard the release of chlorpheniramine maleate from beaded substrate.