DEVELOPMENT AND EVALUATION OF ORAL ELEMENTARY OSMOTIC PUMP TABLETS FOR ROPINIROLE HYDROCHLORIDE

Abstract

The objective of the present study was to develop a sustained release once a day oral elementary osmotic tablet for ropinirole hydrochloride and evaluate its in vivo performance. The core of elementary osmotic tablet of ropinirole hydrochloride was prepared by compression of mixture consisting of drug,different concentrations of osmogens, and other tablet material. Core tablets were then coated with different concentrations of cellulose acetate and PEG-400. FTIR was used to identify if the excipients are compatible with the drug. All the tablets that were prepared were evaluated for drug release and based on the results an optimum and ideal osmotic pump composition with a zero-order drug release extended for 24 h was proposed and this was considered the optimized formulation. Surface morphology of coated formulation was studied by scanning electron microscopy. The drug release was determined in different pH media and different agitation speeds. The pharmacokinetics of the drug after oral administration of optimized osmotic pump was investigated in rabbits and the data were compared with that of a conventional tablet. In vitro in vivo correlation was determined for the optimized formulation. A suitable and simple sustained release elementary osmotic pump for ropinirole hydrochloride was developed. The release rate was independent of the pH of the dissolution medium and the agitation speeds. In vivo studies with optimized osmotic tablet formulation demonstrated that drug concentration in plasma was maintained for prolonged period and minimized fluctuation. A better in vitro in vivo correlation was achieved with the osmotic tablet. A simple once a day elementary osmotic tablet is feasible for ropinirole hydrochloride.