Bioadhesive vaginal drug delivery of nystatin using a derivatized polymer: Development and characterization.

Increasing incidence of resistance to azole antifungals has highlighted the importance of the use of alternative therapeutic agents such as nystatin for the treatment of vulvovaginal candidiasis. The aim of the present study was to develop and characterize locally acting, film formulation for the treatment of candidiasis using a derivatized natural polymer. Derivatization of natural polymer was carried out in order to introduce anionic character to an otherwise neutral polymer, so as to enhance its interaction with vaginal mucous membrane along with inheriting the biocompatibility and nonirritant characteristics of its parent polymer. A carboxymethyl derivative of fenugreek gum (CMFG) was prepared, and characterized by DSC, FTIR and X-ray diffraction studies. The derivatized gum was found to possess bioadhesive and film forming properties. A 3(2) factorial design was employed to formulate vaginal films and a response surface methodological approach was used to study the effect of formulation variables on film properties. Films containing 5% w/v polymer and 2% v/v glycerol exhibited optimum properties in vitro. The optimized drug loaded formulation was able to release 100% drug over a period of 5h and followed Korsmeyer-Peppas kinetics. It was found to be non-irritant and nontoxic to vaginal mucosa and showed appropriate antifungal properties in vivo.