THE Formulation and In-vitro evaluation of press coated tablets of pravastatin for pulsatile drug delivery

The aim of present study is to formulate and evaluate Pravastatin pulsatile drug delivery system by press coated method to mimic the circadian rhythm of the disease by releasing the drug with a distinct predetermined lag time of 6 hrs. The basic design of the system consists of a rapid release core and controlled release coat. Core blend was evaluated for flow properties, hardness, thickness, friability and invitro drug release. Invitro drug release studies of press coated tablets for various formulations i.e., P1F6-P5F6 was conducted. From the results obtained by executed trails P5F6 of coated tablet containing 50% of ethyl cellulose and 20% of HPMC K15M concentration shows lag time up to 6hr and followed by complete drug release at the end of 8hr. Among these, P5F6 was considered as optimized formulation based on the lag time and percent of drug release (98.96% of drug release in 6 hrs). So, it is selected as optimized formulations for designing pulsatile device.  Keywords: Pravastatin, SSG, lycoat, ethyl cellulose, HPMC K15M, pulsatile drug delivery, Press coated method