Pharmacokinetics, Disposition, and Biotransformation of [<sup>14</sup>C]Omecamtiv Mecarbil in Healthy Male Subjects after a Single Intravenous or Oral Dose
作者:Ashit Trivedi、Jan Wahlstrom、Mia Mackowski、Sandeep Dutta、Edward Lee
DOI:10.1124/dmd.121.000444
日期:2021.8
Omecamtiv mecarbil (OM) is a novel cardiac myosin activator that is currently in clinical development for the treatment of heart failure. The absorption and disposition of [14C]OM (60 µCi) were studied after a single intravenous infusion (35 mg over 1 hour) or oral solution dose (35 mg) in 14 healthy male subjects. Mean recovery of the administered [14C]OM dose was 85.1% and 86.5% over 336 hours for the intravenous and oral routes, respectively. After intravenous dosing, 47.8% and 37.3% of the dose was recovered in urine and feces, respectively; after oral dosing, 48.6% and 38.0% was recovered in urine and feces, respectively. Unchanged OM accounted for a minor percentage of radioactivity in urine (mean 7.7% of dose) and feces (mean 4.1% of dose) across all subjects. The major metabolites recovered in urine and feces were M3 (decarbamoylation product) and sequential metabolite M4 (lactam of M3), which accounted for means of 26.5% and 11.6% of the administered dose, respectively. The CYP4 family of enzymes was primarily responsible for the formation of M3 based on in vitro studies. Other metabolic pathways accounted for 14.9% of the administered dose. In pooled plasma, OM, M3, and M4 accounted for 83.8%, 6.0%, and 3.3% of the total [14C]OM-related materials. No other plasma metabolites constituted more than 3% of the administered dose. The bioavailability for OM solution was 93.5% after rapid and extensive absorption. SIGNIFICANCE STATEMENT This study characterized the absorption and disposition of OM, a novel small molecule being developed for the treatment of heart failure. OM was primarily cleared through metabolism by the CYP4 family through oxidative cleavage of a terminal carbamate moiety that resembles hydrolysis.
Omecamtiv mecarbil (OM)是一种新型的心脏肌动蛋白激活剂,目前正在进行临床开发以治疗心力衰竭。在14名健康男性受试者中,研究了[14C]OM (60 µCi)在单次静脉输注(35 mg,1小时内)或口服溶液(35 mg)后的吸收和分布。静脉给药和口服给药的平均药物回收率分别为85.1%和86.5%,持续时间为336小时。静脉给药后,尿液和粪便中回收的药物剂量分别为47.8%和37.3%;口服给药后,尿液和粪便中回收的药物剂量分别为48.6%和38.0%。在所有受试者中,未变的OM在尿液中的放射性占总剂量的较小比例(平均7.7%),在粪便中占4.1%。主要在尿液和粪便中回收的代谢物是M3(去氨基化产物)和顺序代谢物M4(M3的内酰胺),分别占给药剂量的平均26.5%和11.6%。根据体外研究,CYP4家族的酶主要负责M3的形成。其他代谢途径占给药剂量的14.9%。在汇总的血浆中,OM、M3和M4分别占总[14C]OM相关物质的83.8%、6.0%和3.3%。没有其他血浆代谢物超过给药剂量的3%。OM溶液的生物利用度在快速和广泛吸收后为93.5%。显著性声明:本研究描述了OM的吸收和分布,OM是一种正在开发用于治疗心力衰竭的新型小分子。OM主要通过CYP4家族的代谢途径清除,这一过程涉及终端氨基甲酸酯部分的氧化裂解,类似于水解反应。