Formulation and evaluation of 5-fluorouracil controlled release chronotherapeutic drug delivery system (CTDDS) for colorectal cancer

Abstract

Objective: As most of the drugs disintegrate and dissolve in stomach before reaching the target site and to substitute intravenous (IV) route based chrono modulated chemotherapy, oral colon target drug delivery system was formed. The aim of this study was to design, develop, and evaluate a colon targeted tablet containing 5-Fluorouracil (5-FU) to give a controlled release effect of drug for colonic cancer with a goal to increase the bioavailability and improve the patient compliance. Methods: Varied concentration of different polymers such as Xanthan gum and Eudragit were used to get an optimized formulation of 5-FU tablet. The prepared formulation was evaluated for pre compression and post compression parameters such as hardness, weight, friability and drug content uniformity. The optimized formulation was further evaluated by Fourier Transformed Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), in-vitro dissolution studies, dissolution kinetic modeling and stability analysis. Results: All pre-formulation tests were within range of USP standards. Friability of all tablets was satisfied. The interference of the polymers was ruled out by FTIR. In-vitro release studies of 5-FU tablets in phosphate buffer of pH 7.0 were performed using a modified diffusion cell that resulted sustained release (90.99% to 92.69% after 12h) and kinetic models depicted the combined diffusion and dissolution mechanism of release. The optimized tablets were found having only physical interactions based on DSC. The product was found stable when evaluated using accelerated stability studies. Conclusion: It was concluded from the studies that the colon target tablet of 5-FU prepared by different concentration of polymers were optimized and can be efficiently used to control the rate of drug release to the colon in the belief of improved therapeutic efficacy and tolerability. Therefore, it is a better alternative for intravenous route based chrono modulated chemotherapy.