Formulation of a extended release tablet containing dexibuprofen

Abstract

Dexibuprofen, or S(+)-ibuprofen, is the pharmacologically effective enantiomer of racemic ibuprofen. Since dexibuprofen has a low melting point, the amorphous form having a high melting point was prepared with the fused solid dispersion method. With the fused solid dispersion of dexibuprofen, immediate release tablets, extended release tablets, and dual release tablets were compressed and their dissolution profiles compared. The dissolution profiles of the extended release and the dual release tablet depended on the amount of used release modulators (PEO 5,000,000). The release profiles of extended release tablets and extended release part of dual release tablets were well fitted to zero-order release model. The correlation coefficient ranged from 0.982 to 0.995. A pharmacokinetic evaluation where healthy volunteers took tablets of DRT-1 (300 mg) once and the reference drug, two tablets of conventional immediate release tablet (Daxfen, 300 mg), with a 6-h interval between them was studied. The 90% confidence interval for the ratio of the logarithmically transformed AUC (0–24 h), C_max (0–6 h), and C_max (6–24 h) values of the dual release tablet compared to those of the conventional immediate release tablet were calculated to be between 0.9176 and 1.0007, 0.9240 and 1.1968, and 0.8713 and 1.1414, respectively. When the immediate release tablet was taken two times with a six hour interval between doses it showed a bioequivalent effect to taking the dual release tablet once within 12 h. The C_max was reached due to the rapid absorption of the immediate release portion of the dual release tablet and the AUC was maintained due to continuous absorption of the extended release portion.