Novel Floating Pulsatile Approach for Chronotherapeutic Release of Indomethacin

The main objective of the present study was to develop a multiple-unit, floating-pulsatile drug delivery system for obtaining no drug release during floating and in the proximal small intestine followed by pulsed, rapid drug release in distal small intestine to achieve chronotherapeutic release of indomethacin. The system developed consists of drug containing core pellets prepared by extrusion-spheronization process, which were coated with an inner pH-dependent layer of Eudragit S100 and outer effervescent layer of sodium bicarbonate and HPMC K100M. Pellets showed instantaneous floating with no drug release in acidic medium followed by pulsed drug release in basic medium. Concentration of HPMC K100M and layering level of effervescent agent significantly affected performance of pellets. The system showed excellent lag phase followed by burst release in the distal small intestine which gives site and time specific delivery of indomethacin acting as per chronotherapy of rheumatoid arthritis.