The aim of the present work was to formulate and evaluate an oral time controlled drug delivery system of doxofylline, based on chronotherapeutic approach for the treatment of nocturnal asthma. In this study, compression coated time release tablets of doxofylline were prepared by compression coating the core tablet using polymers HPMC K4M with EC in various proportions using RSM. The basic idea behind the dosage form development was to investigate effect of coating design on lag time and drug release from directly compressed time-controlled release tablet. The RSM was applied for optimization of the formulation. A 32 full factorial design was used in the present study. The amount of release retarding polymer HPMC K4M (X1) and amount of erodible polymer EC (X2) were selected as independent variables and the % CDR (drug release), lag time and hardness were considered as the dependant variables. The in-vitro drug release profile of the formulations was performed in 0.1 N HCl and pH 7.4 phosphate buffer. The desired lag time of 5 h was obtained for selected formulations and burst release was obtained after the lag time, which was consistent with the demands of chronotherapeutic drug delivery. The results were analyzed with the design expert software and predicted formulation ratios were obtained. Studies were carried out on the prepared optimized formulation to verify the theoretical prediction. The results were found to be within the range. The optimized batch gave a lag time of 5 hr and drug release of 98.9%. Using RSM, with few runs, effective chronomodulated drug delivery of doxofylline can be achieved.
Loading....