The linagliptin (LIN) and pioglitazone HCl (PIO) combination, currently undergoing phase III clinical trials for diabetes mellitus treatment, demonstrated significant improvements in glycemic control. However, the absence of an analytical method for simultaneous determination in biological fluids highlights a crucial gap. This underscores the pressing need for sensitive bioanalytical methods, emphasizing the paramount importance of developing such tools to advance diabetes management strategies and enhance patient care. Herein, a sensitive reverse-phase high-performance liquid chromatography–electrospray ionization-tandem mass spectrometry method was developed for simultaneous determination of LIN and PIO in rat plasma using alogliptin as an internal standard. Chromatographic separation was performed on an Agilent Eclipse Plus C18 (4.6 × 100 mm, 3.5 μm) using an isocratic mobile phase system consisting of ammonium formate (pH 4.5) and methanol using an acetonitrile-induced protein precipitation technique for sample preparation. Multiple reaction monitoring in positive ion mode was used for quantitation of the precursor to production at m/z 473.2 → 419.9 for LIN, 357.1 → 134.2 for PIO, and 340.3 → 116.1 for ALO. The linearity range was 0.5 to 100 and 1 to 2000 ng/mL for LIN and PIO, respectively. The developed method was validated as per US-FDA guidelines and successfully applied to clinical pharmacokinetic and drug–drug interaction studies with a single oral administration of LIN and PIO in rat plasma. Pharmacokinetic parameters of LIN were significantly influenced by the concomitant administration of PIO and vice versa. Molecular modeling revealed the significant interaction of LIN and PIO with P-glycoprotein. Therefore, the drug–drug interaction between LIN and PIO deserves further study to improve drug therapy and prevent dangerous adverse effects.

中文翻译：

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使用 LC-MS/MS 揭示大鼠血浆中利格列汀和盐酸吡格列酮的药代动力学和药物相互作用


利格列汀 (LIN) 和盐酸吡格列酮 (PIO) 组合目前正在进行治疗糖尿病的 III 期临床试验，显示出对血糖控制的显着改善。然而，缺乏同时测定生物体液的分析方法凸显了一个关键的差距。这凸显了对敏感生物分析方法的迫切需求，强调了开发此类工具对于推进糖尿病管理策略和加强患者护理的至关重要性。本文建立了一种灵敏的反相高效液相色谱-电喷雾电离-串联质谱法，以阿格列汀为内标同时测定大鼠血浆中的LIN和PIO。使用由甲酸铵 (pH 4.5) 和甲醇组成的等度流动相系统在 Agilent Eclipse Plus C18 (4.6 × 100 mm, 3.5 µm) 上进行色谱分离，并使用乙腈诱导的蛋白质沉淀技术进行样品制备。采用正离子模式的多反应监测对生产前体进行定量，LIN 的 m/z 为 473.2 → 419.9，PIO 的 m/z 为 357.1 → 134.2，ALO 的 m/z 为 340.3 → 116.1。 LIN 和 PIO 的线性范围分别为 0.5 至 100 和 1 至 2000 ng/mL。所开发的方法根据美国 FDA 指南进行了验证，并成功应用于大鼠血浆中单次口服 LIN 和 PIO 的临床药代动力学和药物相互作用研究。 PIO 的同时给药显着影响 LIN 的药代动力学参数，反之亦然。分子模型揭示了 LIN 和 PIO 与 P-糖蛋白的显着相互作用。 因此，LIN 和 PIO 之间的药物相互作用值得进一步研究，以改善药物治疗并预防危险的不良反应。