Bioequivalence Study of Aspirin Sustained-release Capsules in Healthy Volunteers

OBJECTIVE: To study the bioequivalence and relative bioavailability of aspirin sustained-release capsules. METHODS: A single oral dose( 162.5 mg of test, 150 mg of reference) and multiple oral doses(162.5 mg of test, 150 mg of reference for six days) were given to 20 healthy volunteers in a randomised crossover study. The concentrations of salicylic acid(SA, the metabolite of aspirin) in plasma were determined by HPLC method. The pharmacokinetic parameters were calculated and the bioavailability and bioequivalence of two formulations were evaluated. RESULTS: After a single dose, the pharmacokinetics parameters for SA were as follows: C_(max) were 2.77± 0.68 and 2.62±0.83 mg · L~(-1); t_(1/2) were 11.07± 4.46 and 12.41±5.03 h; t_(max) were 2.87±2.52 and 3.48±2.09 h; AUC_((0-60)) were 62.50±16.06 and 57.36±14.70 mg · h· L~(-1); AUC_((0-inf)) 65.50±18.71 and 61.33±17.45 mg ·h · L~(-1) for tested formulation and reference formulation, respectively. The relative bioavailability was (110.9±19.1)%. Following the multiple dose, C_(min) in the steady state were 0.72±0.26 and 0.78±0.16 mg ·L~(-1), C_(max) 4.78±1.48 mg/L and 4.49±1.45 mg/L, t_(1/2) were 9.06±1.50 and 8.87±1.39 h; AUC~(ss)64.22±14.71 and 61.79± 13.22 mg ·h· L~(-1), DF were 1.44±0.43 and 1.37±0.48 The relative bioavailability (108.9±35.5)%. CONCLUSION: The results showed that the two formulations were bioequivalence.