Background: A new controlled-release formulation of aceclofenac 200 mg (Clanza CR®) developed by Korea United Pharm., Inc., South Korea, for once-daily (od) dosing provides biphasic aceclofenac release consisting of immediate release of 85 mg followed by sustained release of 115 mg. Food has been known to affect the rate and extent of absorption of several drugs, in both immediate-release and controlled-release formulations.
Objective: The aim of this study was to evaluate the relative bioavailability of a new controlled-release formulation of aceclofenac (200 mg od; Clanza CR®) in comparison with immediate-release aceclofenac (100 mg twice daily [bid], Airtal®) and to assess the effect of food on the pharmacokinetics of the new controlled-release aceclofenac formulation.
Methods: This study was designed as a randomized, open-label, three treatment-period, crossover, single-centre study with a 1-week washout in 41 healthy adults. The three treatments consisted of immediate-release aceclofenac 100 mg bid administered under fasting conditions; controlled-release aceclofenac 200 mg od administered under fasting conditions; and controlled-release aceclofenac 200 mg od administered immediately after a standardized high-fat breakfast. Plasma concentrations of aceclofenac were determined using a high-performance liquid chromatography method.
Results: In the fasted state, the 90% confidence intervals (CIs) of the least squares geometric mean ratios (GMRs) for the area under the plasma concentration-time curve from time zero to 24 hours (AUC(24)) and the peak plasma concentration (C(max)) of aceclofenac for the controlled-release and immediate-release formulations of aceclofenac were all within the bioequivalence criteria range of 0.8-1.25. The 90% CIs of the GMRs for the AUC(24) and C(max) of aceclofenac for the controlled-release formulation of aceclofenac in the fed and fasted states were also within the bioequivalence range. Both aceclofenac formulations were well tolerated in all subjects, and no serious adverse effects were observed.
Conclusion: The results demonstrate that controlled-release aceclofenac 200 mg is equivalent to immediate-release aceclofenac 100 mg when administered at the same total daily dose. Additionally, the bioavailability of controlled-release aceclofenac was not affected by high-fat foods.