INTRODUCTION AND OBJECTIVES Allergic rhinitis is a condition with high global prevalence most effectively treated with antihistamines and antileukotrienes. This study aimed to evaluate the bioequivalence of fexofenadine and montelukast in a fixed-dose combination tablet versus the components administered simultaneously. MATERIALS AND METHODS An open, randomized, 2×2 crossover study was performed in 78 healthy volunteers. Fexofenadine-montelukast tablets containing 120 mg and 10 mg, respectively, were used as the test treatment, and 120 mg fexofenadine tablets and 10 mg montelukast tablets were used as the reference treatment. Concentrations of fexofenadine and montelukast in plasma were determined by protein precipitation and analysis by liquid chromatography/mass spectrometry or liquid chromatography tandem mass spectrometry. RESULTS The 90% confidence intervals (CIs) obtained for fexofenadine were 87.612-102.144 for area under the curve of the plasma concentration after administration to the last concentration (AUC0-t), 88.471-102.282 for the AUC of the plasma concentration extrapolated to infinity (AUC0-∞), and 91.413-108.544 for the maximum plasma concentration (Cmax). For montelukast, they were 96.418-108.416 for AUC0-t, 93.273-106.642 for AUC0-∞ and 94.749-110.178 for Cmax. The ratio and CIs of the values subjected to logarithmic transformation for each parameter were within the range of acceptability of 80%-125%, demonstrating the bioequivalence of the combined fixed-dose tablet to the components administered separately at the same doses. No adverse events were recorded during the study. CONCLUSIONS This study has shown the bioequivalence of the combined fixed-dose tablet, which may be considered a new alternative for the treatment of allergic rhinitis.

中文翻译：

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固定剂量组合片剂中非索非那定和孟鲁司特与同时给药的成分的生物利用度评估。

引言和目标 过敏性鼻炎是一种在全球范围内流行的疾病，抗组胺药和抗白细胞三烯类药物治疗最有效。本研究旨在评估非索非那定和孟鲁司特在固定剂量复方片剂中与同时给药的成分的生物等效性。材料和方法 在 78 名健康志愿者中进行了一项开放、随机、2×2 交叉研究。分别含有120mg和10mg的非索非那定-孟鲁司特片作为试验治疗，120mg非索非那定片和10mg孟鲁司特片作为参比治疗。血浆中非索非那定和孟鲁司特的浓度通过蛋白质沉淀和液相色谱/质谱或液相色谱串联质谱分析来确定。结果 非索非那定的 90% 置信区间 (CIs) 为 87.612-102.144，给药至最后浓度后的血浆浓度曲线下面积 (AUC0-t)，外推至无穷大的血浆浓度 AUC 为 88.471-102.282 (AUC0-∞)，最大血浆浓度 (Cmax) 为 91.413-108.544。对于孟鲁司特，AUC0-t 为 96.418-108.416，AUC0-∞ 为 93.273-106.642，Cmax 为 94.749-110.178。各参数经对数变换后的比值和置信区间均在80%-125%的可接受范围内，证明复方固定剂量片剂与相同剂量单独给药组分的生物等效性。在研究期间没有记录到不良事件。