阿昔替尼的临床药理学。
Clinical pharmacology of axitinib.
机构信息
Clinical Pharmacology, Pfizer Inc., 10555 Science Center Drive, San Diego, CA 92121, USA.
出版信息
Clin Pharmacokinet. 2013 Sep;52(9):713-25. doi: 10.1007/s40262-013-0068-3.
Axitinib is a potent and selective second-generation inhibitor of vascular endothelial growth factor receptors 1, 2, and 3 that is approved in the US and several other countries for treatment of patients with advanced renal cell carcinoma after failure of one prior systemic therapy. The recommended clinical starting dose of axitinib is 5 mg twice daily, taken with or without food. Dose increase (up to a maximum of 10 mg twice daily) or reduction is permitted based on individual tolerability. Axitinib pharmacokinetics are dose-proportional within 1-20 mg twice daily, which includes the clinical dose range. Axitinib has a short effective plasma half-life (range 2.5-6.1 h), and the plasma accumulation of axitinib is in agreement with what is expected based on the plasma half-life of the drug. Axitinib is absorbed relatively rapidly, reaching maximum observed plasma concentrations (C max) within 4 h of oral administration. The mean absolute bioavailability of axitinib is 58 %. Axitinib is highly (>99 %) bound to human plasma proteins with preferential binding to albumin and moderate binding to α1-acid glycoprotein. In patients with advanced renal cell carcinoma, at the 5-mg twice-daily dose in the fed state, the geometric mean (% coefficient of variation) C max and area under the plasma concentration-time curve (AUC) from time 0-24 h (AUC24) were 27.8 ng/mL (79 %) and 265 ng·h/mL (77 %), respectively. Axitinib is metabolized primarily in the liver by cytochrome P450 (CYP) 3A4/5 and, to a lesser extent (<10 % each), by CYP1A2, CYP2C19, and uridine diphosphate glucuronosyltransferase (UGT) 1A1. The two major human plasma metabolites, M12 (sulfoxide product) and M7 (glucuronide product), are considered pharmacologically inactive. Axitinib is eliminated via hepatobiliary excretion with negligible urinary excretion. Although mild hepatic impairment does not affect axitinib plasma exposures compared with subjects with normal hepatic function, there was a 2-fold increase in AUC from time zero to infinity (AUC∞) following a single 5-mg dose in subjects with moderate hepatic impairment. In the presence of ketoconazole, a strong CYP3A4/5 inhibitor, axitinib C max and AUC∞ increased by 1.5- and 2-fold, respectively, whereas co-administration of rifampin, a strong CYP3A4/5 inducer, resulted in a 71 and 79 % decrease in the C max and AUC∞, respectively. Axitinib does not inhibit CYP3A4/5, CYP1A2, CYP2C8, CYP2A6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, or UGT1A1 at concentrations obtained with the clinical doses and is not expected to have major interactions with drugs that are metabolized by these enzymes. Axitinib is an inhibitor of the efflux transporter P-glycoprotein (P-gp) in vitro, but is not expected to inhibit P-gp at therapeutic plasma concentrations. A two-compartment population pharmacokinetic model with first-order absorption and lag time was used to describe axitinib pharmacokinetics. No clinically relevant effects of age, sex, body weight, race, renal function, UGT1A1 genotype, or CYP2C19 inferred phenotype on the clearance of axitinib were identified.
阿昔替尼是一种强效和选择性的第二代血管内皮生长因子受体 1、2 和 3 抑制剂,在美国和其他几个国家被批准用于治疗接受过一种系统治疗后进展的晚期肾细胞癌患者。阿昔替尼的推荐临床起始剂量为 5mg,每日两次,可与食物同服或不同服。根据个体耐受性,可以增加(最高可达每日两次 10mg)或减少剂量。阿昔替尼的药代动力学在 1-20mg,每日两次的范围内呈剂量比例,包括临床剂量范围。阿昔替尼的有效血浆半衰期较短(范围为 2.5-6.1 小时),并且阿昔替尼的血浆蓄积与根据药物半衰期预期的情况一致。阿昔替尼吸收较快,口服后 4 小时内达到最大观察到的血浆浓度(C max)。阿昔替尼的绝对生物利用度为 58%。阿昔替尼与人血浆蛋白高度结合(>99%),优先与白蛋白结合,与 α1-酸性糖蛋白中度结合。在接受 5mg,每日两次剂量的晚期肾细胞癌患者中,在进食状态下,从 0 到 24 小时的 C max和血浆浓度-时间曲线下面积(AUC)(AUC 24 )的几何平均值(%变异系数)分别为 27.8ng/mL(79%)和 265ng·h/mL(77%)。阿昔替尼主要通过细胞色素 P450(CYP)3A4/5 代谢,在肝脏中代谢,在较小程度上(<10%)通过 CYP1A2、CYP2C19 和尿苷二磷酸葡萄糖醛酸转移酶(UGT)1A1 代谢。两种主要的人血浆代谢产物 M12(亚砜产物)和 M7(葡萄糖醛酸产物)被认为无药理活性。阿昔替尼通过肝胆排泄消除,尿液排泄可忽略不计。虽然轻度肝损伤与肝功能正常的受试者相比,对阿昔替尼的血浆暴露没有影响,但中度肝损伤受试者单次 5mg 剂量后,AUC 0-无穷大(AUC∞)增加了 2 倍。在酮康唑(一种强 CYP3A4/5 抑制剂)存在下,阿昔替尼的 C max 和 AUC∞分别增加了 1.5 倍和 2 倍,而利福平(一种强 CYP3A4/5 诱导剂)联合用药时,C max 和 AUC∞分别降低了 71%和 79%。阿昔替尼在临床剂量下获得的浓度不会抑制 CYP3A4/5、CYP1A2、CYP2C8、CYP2A6、CYP2C9、CYP2C19、CYP2D6、CYP2E1 或 UGT1A1,预计不会与这些酶代谢的药物发生重大相互作用。阿昔替尼是体外 P-糖蛋白(P-gp)外排转运蛋白的抑制剂,但预计在治疗性血浆浓度下不会抑制 P-gp。采用具有一级吸收和滞后时间的两室群体药代动力学模型来描述阿昔替尼的药代动力学。年龄、性别、体重、种族、肾功能、UGT1A1 基因型或 CYP2C19 推断表型对阿昔替尼清除率无临床相关影响。