Bioequivalence Study of Two Formulations of Ibuprofen Arginine Granules in Healthy Chinese Adult Subjects

Objective: To evaluate the bioequivalence and safety of the test and reference formulations of ibuprofen arginine granules (400 mg) in healthy Chinese adult subjects under fasting and fed conditions. Methods: This was a randomized, open-label, single-center, single-dose, two-treatment, two-sequence, two-period crossover bioequivalence study conducted in separate fasting and fed cohorts. A total of 84 healthy Chinese adults were enrolled, including 34 subjects in the fasting cohort and 50 subjects in the fed cohort. Subjects were randomized to receive either the test formulation followed by the reference formulation or the reverse sequence, with a washout period of at least 2 days between treatments. Plasma ibuprofen concentrations were measured using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Pharmacokinetic parameters were calculated using non-compartmental analysis, and bioequivalence was assessed based on geometric mean ratios (GMRs) and corresponding 90% confidence intervals (CIs) for Cmax, AUC0-t, and AUC0-∞. Results: Under fasting conditions, the GMRs (90% CIs) of the test versus reference formulation for AUC0-t, AUC0-∞, and Cmax were 1.0008 (0.9698–1.0327), 1.0023 (0.9710–1.0346), and 0.9825 (0.9383–1.0288), respectively. Under fed conditions, the corresponding values were 0.9916 (0.9755–1.0081), 0.9776 (0.9432–1.0133), and 0.9982 (0.9431–1.0567). All 90% CIs were within the predefined bioequivalence acceptance range of 80.00%-125.00%. No serious adverse events, deaths, or study discontinuations due to adverse events occurred. All treatment-emergent adverse events were mild and resolved without sequelae. Conclusion: The test and reference formulations of ibuprofen arginine granules were bioequivalent under both fasting and fed conditions in healthy Chinese adult subjects. Both formulations were generally safe and well tolerated, with comparable safety profiles.