Bioavailability of ibuprofen from matrix mini-tablets based on a mixture of starch and microcrystalline wax

The bioavailability of ibuprofen from matrix mini-tablets based on microcrystalline wax and a starch derivative was tested. An oral dose of 300 mg of ibuprofen was administered to healthy volunteers (n = 8) in a randomized cross-over study design either as a commercial matrix formulation (Ibu-Slow(R) 600) or as mini-tablets (filled into hard gelatin capsules). The mini-tablets consisted of 60% ibuprofen, 15% Paracera(R) M (wax), 22.5% DDWM (starch) and 2.5% triacetin (lubricant). t(50%) of the in vitro release was 4.5 and 5 h for the mini-tablet and Ibu-slow(R) formulations, respectively. Both formulations behaved in vivo as sustained-release formulation; their HVDt50%Cmax value was determined at 5.6 and 5.1 h for the mini-tablet and Ibu-slow(R) formulations, respectively. A significantly higher value of C-max was seen for the mini-tablet formulation, resulting in a relative bioavailability of 116 +/- 22.6% compared to the Ibu-slow(R) matrix. These data demonstrate that the experimental mini-tablets can be used to formulate sustained-release dosage forms. (C) 2000 Elsevier Science B.V. All rights reserved.