Abstract

DEVELOPMENT OF MULTILAYER TABLETS OF NIACIN COATED BY ROSUVASTATIN CALCIUM

Babita Kumari*, H. K. Jain, P. Sharma and B. Srivastava

ABSTRACT

The objective of the study was to designed fixed dose combined multilayer tablets of two lipid lowering drugs of different mechanism of action namely, niacin (NA) and rosuvastatin calcium (RC) to give immediate release of RC and extended release of NA. The immediate release layer (outermost layer comprised of RC and HPMC K15) coated over the extended release core (innermost) comprised of NA and different concentration of HPMC K100M as the release retarding polymers. These two were separated by a middle inert layer barrier consists of HPMC 3cps. This is more suitable for the delivery of two drugs which may have interactions in them. Wet granulation method was employed for formulation of the NA core tablets. Various pre-formulation studies of NA and RC, prior to granulation, like flow properties evaluation, solubility studies and drug excipient compatibility were performed. The multilayer tablets were evaluated for weight variation, hardness, friability, drug content, and in-vitro drug release using USP dissolution apparatus type I (basket). More than 85% of RC was released within 45 min. HPMC K100M extended the release of NA for 24 hr. After stability tests, drugs contents were found within the range. The release of NA was found to follow a mixed pattern of Korsmeyer-Peppas, Higuchi model and zero order release models and the kinetic studies of the formulations revealed that diffusion is the predominant mechanism of drug release. The stability studies as per ICH guidelines were carried out for the optimized batch for six months and it showed acceptable results.

Keywords: Niacin, Rosuvastatin calcium, Multilayer tablets, HPMC K100M.