肝脏和第一通路CYP3A活动的静脉和口腔试验中的内主体变异性
Evan D Kharasch1,2, Christine Hoffer3, Pamela Bedynek3
1Department of Anesthesiology, Duke University School of Medicine, 905 S. LaSalle St, GSRB1 Room 2031, Box 3094, Durham, NC, 27710, USA. evan.kharasch@duke.edu.
Clinical pharmacokinetics
|July 29, 2024
概括
米达佐拉姆和阿尔芬坦尼尔对细胞染色体P450 3A (CYP3A) 活性探针具有相似的个体内变异性. 一次性血度的变化比曲线下的面积 (AUC) 和清除度量更高.
科学领域:
- 药理动力学和药物新陈代谢
- 细胞染色体P450酶活性评估
- 药物相互作用研究 药物相互作用研究
背景情况:
- 静脉注射 (IV) 和口服米达佐拉姆和阿尔芬坦尼尔是评估肝脏和第一通细胞染色体P450 3A (CYP3A) 活性的确立探针.
- 这些探针对于理解药物相互作用和表型化CYP3A酶活性至关重要.
- 最小的内体变异性是理想的药理动力学探针的关键特征,但对于常见的CYP3A探针来说,这还没有得到很好的定义.
研究的目的:
- 为了确定米达佐拉姆和阿尔芬坦尼尔的个体内 (日间) 变异性,用于评估肝脏和首通CYP3A活性.
- 为了比较等离子体度-时间曲线下面积的变化,将其推断到无限 (AUC0-∞) 和清除与一次性等离子体度的变化.
- 评估瞳孔直径变化作为阿尔芬坦尼尔血度的非侵入性替代品及其人内变异性.
主要方法:
- 12名健康的志愿者参与了为期四个周期的交叉研究,每个周期相隔大约两周.
- 参与者在每个期间都接受了静脉注射 (IV) 和口服剂量的米达佐拉姆和阿尔芬坦尼尔.
- 使用液态染色体质谱法 (LCMS) 测量了血药物度,并记录了瞳孔直径;使用非分区方法分析数据.
主要成果:
- 静脉米达佐拉姆AUC0-∞和清除的内体变异率 (%CV) 为12%,而静脉阿尔芬坦尼尔则为15-16%.
- 口服的米达佐拉姆和阿尔芬坦尼尔在AUC0-∞ (19-20%) 和清除 (18-21%) 中显示了略高的个体内变异性.
- 与AUC0-∞和清除相比,单一时间点血度和瞳孔微小化 (阿尔夫坦尼尔效应) 显示出更大的个体内变异性.
结论:
- 米达佐拉姆和阿尔芬坦尼尔在清除率和AUC0-∞指标方面表现出可比的个体内变异性,表明与CYP3A探针相似的可靠性.
- 单次血度测量不如AUC0-∞或清除,由于更高的内部变异性.
- 瞳孔肌瘤是阿尔芬坦尼尔的可行的实时替代品,但其人内变异性高于药理学参数.
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