Treatment of multidrug-resistant tuberculosis (MDR-TB) is challenging due to high treatment failure rate and adverse drug events. This study aimed to develop and validate a simple LC-MS/MS method for simultaneous measurement of five TB drugs in human plasma and to facilitate therapeutic drug monitoring (TDM) in MDR-TB treatment to increase efficacy and reduce toxicity. Moxifloxacin, levofloxacin, prothionamide, pyrazinamide and ethambutol were prepared in blank plasma from healthy volunteers and extracted using protein precipitation reagent containing trichloroacetic acid. Separation was achieved on an Atlantis T3 column with gradient of 0.1% formic acid in water and acetonitrile. Drug concentrations were determined by dynamic multiple reaction monitoring in positive ion mode on a LC-MS/MS system. The method was validated according to the United States’ Food and Drug Administration (FDA) guideline for bioanalytical method validation. The calibration curves for moxifloxacin, levofloxacin, protionamide, pyrazinamide and ethambutol were linear, with the correlation coefficient values above 0.993, over a range of 0.1-5, 0.4-40, 0.2-10, 2-100 and 0.2-10 mg/L, respectively. Validation showed the method to be accurate and precise with bias from 6.5% to 18.3% for lower limit of quantification and -5.8% to 14.6% for LOW, medium (MED) and HIGH drug levels, and with coefficient of variations within 11.4% for all levels. Regarding dilution integrity, the bias was within 7.2% and the coefficient of variation was within 14.9%. Matrix effect (95.7%-112.5%) and recovery (91.4%-109.7%) for all drugs could be well compensated by their isotope-labelled internal standards. A benchtop stability test showed that the degradation of prothionamide was over 15% after placement at room temperature for 72 h. Clinical samples (n= 224) from a cohort study were analyzed and all concentrations were within the analytical range. The signal of prothionamide was suppressed in samples with hemolysis which was solved by sample dilution. As the method is robust and sample preparation is simple, it can easily be implemented to facilitate TDM in programmatic MDR-TB treatment.

由于高治疗失败率和不良药物事件，耐多药结核病（MDR-TB）的治疗具有挑战性。这项研究旨在开发和验证一种简单的LC-MS / MS方法，用于同时测量人血浆中的五种结核病药物，并促进MDR-TB治疗中的治疗性药物监测（TDM），以提高疗效并降低毒性。从健康志愿者的空白血浆中制备莫西沙星，左氧氟沙星，乙硫酰胺，吡嗪酰胺和乙胺丁醇，并使用含三氯乙酸的蛋白质沉淀试剂进行提取。在Atlantis T3色谱柱上进行分离，梯度为0.1％的甲酸在水和乙腈中的梯度。通过在LC-MS / MS系统上以阳离子模式进行动态多反应监测来确定药物浓度。该方法已根据美国食品药品管理局（FDA）的生物分析方法验证指南进行了验证。莫西沙星，左氧氟沙星，丙酰胺，吡嗪酰胺和乙胺丁醇的校准曲线为线性，相关系数值在0.9-5 mg / L，0.1-5、0.4-40、0.2-10、2-100和0.2-10 mg / L范围内， 分别。验证显示该方法准确准确，对于定量下限，偏差为6.5％至18.3％，对于LOW，中（MED）和HIGH药物水平，偏差为-5.8％至14.6％，并且偏差系数在11.4％以内所有级别。关于稀释完整性，偏差在7.2％以内，变异系数在14.9％以内。基质效应（95.7％-112.5％）和回收率（91.4％-109）。7％）的所有药物都可以通过同位素标记的内标物得到很好的补偿。台式稳定性测试表明，在室温下放置72小时后，乙硫酰胺的降解率超过15％。分析来自队列研究的临床样本（n = 224），所有浓度均在分析范围内。溶血样品中的乙硫酰胺信号被抑制，可通过稀释样品来解决。由于该方法功能强大且样品制备简单，因此可轻松实施以促进TDM用于程序性MDR-TB治疗。溶血样品中的乙硫酰胺信号被抑制，可通过稀释样品来解决。由于该方法功能强大且样品制备简单，因此可轻松实施以促进TDM用于程序性MDR-TB治疗。溶血样品中的乙硫酰胺信号被抑制，可通过稀释样品来解决。由于该方法功能强大且样品制备简单，因此可轻松实施以促进TDM用于程序性MDR-TB治疗。