CODEN : IJPNL 6 A novel drug delivery system designed for modulating the release kinetics of anti - tubercular drugs

The major clinical issue with TB therapy is the poor oral bioavailability of rifampicin in the presence of isoniazid in acidic medium. The present work was undertaken to develop a novel solid dosage form (tablet and capsule in capsule) comprising a immediate release rifampicin tablet, effervescent gastro retentive rifampicin tablet and an enteric coated isoniazid capsule that can differentiately release rifampicin in a controlled manner in the stomach and isoniazid in the intestine. Rifampicin GRDDS was formulated using different concentrations of HPMCK4M and HPMCK100M as matrixing agent. Enteric coated isoniazid capsule was formulated using eudragit L100-55. Drug release and drug degradation of the novel dosage form was compared with R-Cinex. About 42% of rifampicin was degraded to 3FRSV from R-Cinex at the end of 60 mins whereas only 10% of rifampicin degraded in case of novel dosage form. Hence, the minimization of contact between rifampicin and isoniazid by sustaining the release of rifampicin can alleviate its degradation to a certain extent.