Bioequivalence Study of Two Orodispersible Rizatriptan Formulations of 10 mg in Healthy Volunteers

The aim of the study was to assess the bioequivalence and tolerability of two different oral formulations of rizatriptan. A bioequivalence study was carried out in 40 healthy volunteers according to an open label, randomized, two-period, two-sequence, crossover, single dose, and fasting conditions design. The test and reference formulations were administered in two treatment days, separated by a washout period of seven days. Plasma concentrations of rizatriptan were obtained by the LC/MS/MS (Liquid chromatography tandem-mass spectrometry) method. Log-transformed AUC_0-t (area under the plasma concentration-time curve from zero to the last measurable concentration) and C_max (maximum plasma concentration) values were tested for bioequivalence based on the ratios of the geometric means (test/reference). The t_max (time to reach maximum plasma concentration) was analysed nonparametrically. The 90% confidence intervals of the geometric mean values for the test/reference ratios for AUC_0-t and C_max were within the bioequivalence acceptance range of 80%-125%. According to the European Guideline, it may therefore be concluded that the test formulation of rizatriptan 10 mg orodispersible tablet is bioequivalent to the reference formulation (Maxalt^® Max 10 mg oral lyophilisate). The safety profile of both formulations was consistent with the summary of the product characteristics.