Larotrectinib is a first‐generation tropomyosin kinase inhibitor, approved for the treatment of solid tumors. In this paper, we present a validated dried blood spot (DBS) method for the quantitation of larotrectinib from mouse blood using HPLC–MS/MS, which was operated under multiple reaction monitoring mode. To the DBS disc cards, acidified methanol enriched with internal standard (IS; enasidenib) was added and extracted using tert‐butyl methyl ether as an extraction solvent with sonication. Chromatographic separation of larotrectinib and the IS was achieved on an Atlantis dC₁₈ column using 10 mm ammonium formate–acetonitrile (30:70, v/v) delivered at a flow‐rate of 0.80 ml/min. Under these optimized conditions, the retention times of larotrectinib and the IS were ~0.93 and 1.37 min, respectively. The total run time was 2.50 min. Larotrectinib and the IS were analyzed using positive ion scan mode and parent–daughter mass to charge ion (m/z) transitions of 429.1 → 342.1 and 474.1 → 267.1, respectively, were used for the quantitation. The calibration range was 1.06–5,080 ng/ml. No matrix effect or carryover was observed. Hematocrit did not influence DBS larotrectinib concentrations. All of the validation parameters met the acceptance criteria. The applicability of the validated method was shown in a mouse pharmacokinetic study.

中文翻译：

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HPLC-MS / MS的干血斑测定法测定小鼠血液中的larotrectinib及其在药代动力学研究中的应用。

Larotrectinib是第一代原肌球蛋白激酶抑制剂，已被批准用于治疗实体瘤。在本文中，我们提出了一种经过验证的干血斑（DBS）方法，该方法使用HPLC-MS / MS从小鼠血液中定量拉罗替尼，该方法在多种反应监测模式下进行。在DBS光盘卡中，添加了富含内标（IS; enasidenib）的酸化甲醇，并使用叔丁基甲基醚作为萃取溶剂并进行超声处理进行萃取。在10 m m的Atlantis dC ₁₈色谱柱上完成larotrectinib和IS的色谱分离甲酸铵-乙腈（30:70，v / v）的流速为0.80 ml / min。在这些优化条件下，拉罗替尼和IS的保留时间分别约为0.93和1.37分钟。总运行时间为2.50分钟。使用正离子扫描模式分析了Larotrectinib和IS，并使用了429.1→342.1和474.1→267.1的母-子质荷比（m / z）跃迁进行定量。校准范围是1.06-5,080 ng / ml。没有观察到基质效应或残留。血细胞比容不影响DBS拉罗替尼的浓度。所有验证参数均符合验收标准。小鼠药代动力学研究表明了该方法的适用性。