Polymeric mucoadhesive tablets for topical or systemic buccal delivery of clonazepam: Effect of cyclodextrin complexation

Two kinds of mucoadhesive buccal tablets of clonazepam (CLZ) were developed to provide, a prolonged local or systemic delivery respectively. Tablets prepared by direct compression of combinations of different polymers were tested for swelling, erosion and residence time properties. Carbopol 971P/hydroxypropylmethylcellulose and Poloxamer/chitosan mixtures were the best and were selected for drug loading. The effect of CLZ complexation with different cyclodextrins was investigated. Randomly methylated-beta CD (RAME beta CD) was the most effective, allowing 100% drug released increase from local-delivery buccal tablets. Kollicoat was the best among the tested backing-layers, assuring a unidirectional release from systemic-delivery buccal tablets (<0.8% drug released in simulated saliva after 24 h). In vitro permeation studies from coated-tablets showed that CLZ loading as RAME beta CD-coground enabled a 5-times increase in drug flux and permeability. Therefore, complexation with RAME beta CD was a successful strategy to improve the CLZ performance from buccal tablets for both local or systemic action.