Development of new controlled release formulation of flurbiprofen: In vitro - in vivo correlation

A novel matrix system of flubiprofen as an oral controlled release formulation was prepared using gum karaya as release retardant. Lactose or dicalcium phosphate was incorporated to improve the drug release rate. Gum karaya matrices containing lactose showed satisfactory release characteristics. Flurbiprofen-gum karaya matrices showed first order release kinetics following super case II transport, where as matrices with both of the co-excipient followed first order kinetics with anomalous diffusion release. The selected experimental formulation showed comparable In vitro dissolution profile and in vivo blood level pattern with those of the commercial sustained release formulation. The data support a Level A correlation between in vitro release rate profile and In vivo absorption for flurbiprofen from both the formulations.