Larotrectinib is an orally administered drug and the first and only selective pan-tropomyosin receptor kinase (TRK) inhibitor in clinical development to treat cancer patients harboring a neurotrophic receptor tyrosine kinase gene fusion. In this study, an analytical method to quantify the TRK inhibitor in mouse and human plasma was developed and validated using LC-MS/MS following protein precipitation with acetonitrile. Larotrectinib and an internal standard (carbamazepine) were separated from endogenous substances using an Xterra C18 column with acetonitrile containing 0.1% formic acid as the mobile phase. The ions m/z 429.8 → 342.8 for larotrectinib and m/z 237.0 → 194.0 for carbamazepine detected in multiple reaction monitoring mode were used for the quantitation. The detector response of larotrectinib was linear within the concentration range 5–10,000 ng/mL with a correlation coefficient ( r 2 ) of not less than 0.999. The intra- and inter-day precision and accuracy were less than 10.48% and within − 8.99%, respectively, in mouse and human plasma. Larotrectinib was stable under various storage and handling conditions, and no significant matrix effect was observed in both mouse and human plasma. Finally, the assay was successfully applied to the pharmacokinetic study of larotrectinib after its intravenous and oral administration to mice.

中文翻译：

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用于监测小鼠和人血浆中原肌球蛋白相关激酶抑制剂 larotrectinib 的 LC-MS/MS 方法的开发和验证及其在药代动力学研究中的应用

Larotrectinib 是一种口服药物，也是临床开发中第一个也是唯一一个选择性泛原肌球蛋白受体激酶 (TRK) 抑制剂，用于治疗携带神经营养受体酪氨酸激酶基因融合的癌症患者。在本研究中，开发了一种量化小鼠和人血浆中 TRK 抑制剂的分析方法，并在用乙腈沉淀蛋白质后使用 LC-MS/MS 进行了验证。使用含有 0.1% 甲酸的乙腈作为流动相的 Xterra C18 色谱柱将 Larotrectinib 和内标物（卡马西平）与内源性物质分离。在多反应监测模式下检测到的离子 m/z 429.8 → 342.8 的 larotrectinib 和 m/z 237.0 → 194.0 的卡马西平用于定量。larotrectinib 的检测器响应在 5–10,000 ng/mL 浓度范围内呈线性，相关系数 (r 2 ) 不小于 0.999。在小鼠和人血浆中，日内和日间精密度和准确度分别低于 10.48% 和 - 8.99%。Larotrectinib 在各种储存和处理条件下稳定，在小鼠和人血浆中均未观察到显着的基质效应。最后，该测定成功应用于小鼠静脉和口服给药后的拉罗替尼的药代动力学研究。Larotrectinib 在各种储存和处理条件下稳定，在小鼠和人血浆中均未观察到显着的基质效应。最后，该测定成功应用于小鼠静脉和口服给药后的拉罗替尼的药代动力学研究。Larotrectinib 在各种储存和处理条件下稳定，在小鼠和人血浆中均未观察到显着的基质效应。最后，该测定成功应用于小鼠静脉和口服给药后的拉罗替尼的药代动力学研究。