Pharmacokinetics, Bioequivalence, and Safety of Diclofenac Sodium Sustained-Release Tablets in Healthy Chinese Subjects Under Fasting and Fed Conditions

This publication reports two independent bioequivalence trials of domestic diclofenac sodium sustained-release tablets (0.1 g) against a reference formulation in healthy Chinese subjects, conducted separately under fasting and fed conditions using a fully replicated crossover design. Plasma diclofenac was measured by LC-MS/MS, and pharmacokinetic parameters were calculated by non-compartmental analysis in Phoenix WinNonlin, with bioequivalence assessed by average or reference-scaled average bioequivalence depending on the reference formulation's within-subject variability. In both the fasting and fed trials, the 90% confidence intervals for the geometric least-squares mean ratios of Cmax, AUC0-t, and AUC0-inf fell within acceptance limits, demonstrating bioequivalence. Adverse events were mild in both trials, supporting the clinical interchangeability of the test and reference formulations.