Bioequivalence Studies of Rivaroxaban at Two Different Strengths: Rivaroxaban 10 mg under Fasting Conditions and Rivaroxaban 20 mg under Fed Conditions in Healthy Mexican Subjects

The goal of these two studies was to evaluate the bioequivalence of two strengths of rivaroxaban 10 mg and 20 mg. Because the food effect on the pharmacokinetics of rivaroxaban affects the strength of 20 mg and not that of 10 mg. The 20 mg strength study was conducted under fed conditions, whereas the 10 mg strength study was conducted under fasting conditions. The two studies were conducted separately with different sets of Mexican subjects of both genders using a randomized, singledose, 2-sequence, 2-period cross over design with a 7-day washout period. Blood samples from the subjects were obtained at basal conditions, 0.25, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75, 2.00, 2.50, 3.00, 3.50, 4.00, 6.00, 8.00, 10.00, 12.00, 24.00, 36.00 and 48.00 hours after administration. Rivaroxaban plasma concentrations were quantified using an HPLC method coupled to a mass spectrometer. The test and reference formulations were considered to be bioequivalent if the 90% CI for the ratios (test/reference) of geometric means were within the acceptance limits of 80 to 125% for the pharmacokinetic parameters Cmax, AUC0–t and AUC0–∞. In both studies the 90% CI for all pharmacokinetic parameters were within the limits of acceptance. Therefore the conclusion of bioequivalence was reached.