Departments of Pharmacokinetics, Dynamics, and Metabolism, Pfizer Global Research and Development, Pfizer Inc., St. Louis, Missouri, USA.
J Pharmacol Exp Ther. 2010 Sep 1;334(3):936-44. doi: 10.1124/jpet.110.170753. Epub 2010 Jun 2.
N-({(5S)-3-[4-(1,1-dioxidothiomorpholin-4-yl)-3,5-difluorophenyl]-2-oxo-1,3-oxazolidin-5-yl}methyl)acetamide (PNU-288034), an oxazolidinone antibiotic, was terminated in phase I clinical development because of insufficient exposure. Analysis of the drug pharmacokinetic and elimination profiles suggested that PNU-288034 undergoes extensive renal secretion in humans. The compound was well absorbed and exhibited approximately linear pharmacokinetics in the oral dose range of 100 to 1000 mg in human. PNU-288034 was metabolically stable in liver microsomes across species, and unchanged drug was cleared in the urine by an apparent active renal secretion process in rat and monkey (two to four times glomerular filtration rate) but not dog. In vitro studies conducted to characterize the transporters involved demonstrated PNU-288034 uptake by human organic anion transporter 3 (OAT3; K(m) = 44 +/- 5 microM) and human multidrug and toxin extrusion protein 1 (hMATE1; K(m) = 340 +/- 55 microM). The compound was also transported by multidrug resistance P-glycoprotein and breast cancer resistance protein. In contrast, human organic cation transporter 2, human OAT1, and hMATE2-K did not transport PNU-288034. Coadministration of PNU-288034 and the OAT3 inhibitor probenecid significantly increased PNU-288034 plasma area under the curve (170%) and reduced both plasma and renal clearance in monkey. Coadministration of PNU-288034 and cimetidine, a MATE1 inhibitor, also reduced plasma clearance in rat to a rate comparable with probenecid coadministration. Collectively, our results demonstrated a strong in vitro-in vivo correlation for active renal secretion coordinated through the vectorial transport process of OAT3 and MATE1, which ultimately resulted in limiting the systemic exposure of PNU-288034.
N-({(5S)-3-[4-(1,1-二氧代硫代吗啉-4-基)-3,5-二氟苯基]-2-氧代-1,3-恶唑烷-5-基}甲基)乙酰胺(PNU-288034)是一种恶唑烷酮类抗生素,由于暴露量不足,在 I 期临床开发中被终止。对药物药代动力学和消除谱的分析表明,PNU-288034在人体内广泛进行肾脏分泌。该化合物在口服剂量为 100 至 1000mg 范围内被很好地吸收,并表现出近似线性的药代动力学。PNU-288034在跨物种的肝微粒体中代谢稳定,并且未改变的药物通过大鼠和猴子(两次至四次肾小球滤过率)中的明显主动肾脏分泌过程而在尿液中清除,但在狗中不被清除。为了表征所涉及的转运体而进行的体外研究表明,PNU-288034被人有机阴离子转运蛋白 3(OAT3;K(m)=44 +/- 5 microM)和人多药和毒素外排蛋白 1(hMATE1;K(m)=340 +/- 55 microM)摄取。该化合物还被多药耐药 P-糖蛋白和乳腺癌耐药蛋白转运。相比之下,人有机阳离子转运蛋白 2、人 OAT1 和 hMATE2-K 不转运 PNU-288034。PNU-288034 和 OAT3 抑制剂丙磺舒联合给药可显著增加猴体内 PNU-288034 的血浆 AUC(170%),并降低其血浆和肾清除率。PNU-288034 和 MATE1 抑制剂西咪替丁联合给药也可降低大鼠的血浆清除率,使其与丙磺舒联合给药的速率相当。总之,我们的结果表明,主动肾脏分泌具有强大的体外-体内相关性,这与 OAT3 和 MATE1 的载体转运过程相协调,最终导致 PNU-288034 的全身暴露受限。