Pre-formulation Study for Preparation of Mucoadhesive Buccal Tablets Containing Nystatin and Cashew Gum by Direct Compression

Cashew gum is a branched chain heteropolysaccharide extracted from the cashew tree (Anacardium occidentale L.). Purified cashew gum (PCG) is free of plant contaminants and is highly soluble. Several studies have indicated this polymer can be relevant in the pharmaceutical industry for production of tablets. Recently, our research group reported that PCG can be used as a diluent for tablets produced by direct compression. Nystatin (Nys) is the drug of first choice for treatment of oral candidiasis, in the form of a suspension. The treatment consists of up to six daily doses of a suspension of nys at 500,000 IU, causing low therapeutic adhesion by patients. The objective of this study was to investigate the behavior of PCG together with nys and other excipients (flavoring agents and lubricating agent) for future manufacture of mucoadhesive buccal tablets by direct compression. For that purpose, we performed pre-formulation tests (FTIR, TGA, XRD, solubility, pH, granulometry, swelling degree and powder flow) with physical mixtures of the drug and excipients. The results were excellent, demonstrating that PCG is a polymer with potential for this type of application.