代谢
奥西洛卓司他片广泛代谢——大约80%的口服给药剂量以代谢物的形式排出,这是药物清除的主要方式。[L12132]血浆中最丰富的代谢物是M35.4(二氧化的奥西洛卓司他)、M16.5和M24.9,分别占给药剂量的51%、9%和7%。[L12132] M34.5和M24.9代谢物的半衰期长于母药,可能导致每日两次给药时的积累。在尿液中观察到的十三种代谢物中,最丰富的是M16.5(奥西洛卓司他葡萄糖苷酸)、M22(M34.5的葡萄糖苷酸结合物)和M24.9,分别占给药剂量的17%、13%和11%。[L12132] M34.5代谢物在尿液中排出的剂量不到1%,但其葡萄糖苷酸结合物(M22)约占13%。[L12132] 奥西洛卓司他的生物转化由多种细胞色素P450(CYP)和UDP-葡萄糖醛酸转移酶(UGT)酶介导,但没有一种酶对总清除率的贡献超过25%。[L12123] 在总清除率中,大约26%是由CYP介导的,19%是由UGT介导的,50%是由其他酶介导的。[L12132] 主要代谢物M34.5的形成可能是非CYP介导的。奥西洛卓司他葡萄糖苷酸(M16.5)是其主要尿液代谢物的形成由UGT1A4、UGT2B7和UGT2B10催化。[L12132] _体外_数据表明,没有一种代谢物对奥西洛卓司他的治疗效果有贡献,但M34.5代谢物已被涉及在多种酶和转运体的抑制和/或诱导中。[L12123, L12132]
Osilodrostat is extensively metabolized - approximately 80% of an orally administered dose is excreted as metabolites, and this is the predominant means of drug clearance.[L12132] The most abundant metabolites in plasma are M35.4 (di-oxygenated osilodrostat), M16.5, and M24.9 at 51%, 9%, and 7% of the administered dose, respectively.[L12132] The M34.5 and M24.9 metabolites have longer half-lives than the parent drug which may lead to accumulation with twice-daily dosing. Of the thirteen metabolites observed in the urine, the most abundant are M16.5 (osilodrostat glucuronide), M22 (a glucuronide conjugate of M34.5), and M24.9 at 17%, 13%, and 11% of the administered dose, respectively.[L12132] The M34.5 metabolite accounts for less than 1% of the dose excreted in urine, but its glucuronide conjugate (M22) accounts for approximately 13%.[L12132] The biotransformation of osilodrostat is mediated by multiple cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT) enzymes, though no single enzyme appears to contribute >25% to the total clearance.[L12123] Of the total clearance, approximately 26% is CYP-mediated, 19% is UGT-mediated, and 50% is mediated by other enzymes.[L12132] The formation of M34.5, the major metabolite of osilodrostat, is likely non-CYP-mediated. The formation of osilodrostat glucuronide (M16.5), its major urinary metabolite, is catalyzed by UGT1A4, UGT2B7, and UGT2B10.[L12132] _In vitro_ data suggest that none of the metabolites contribute to the therapeutic efficacy of osilodrostat, but the M34.5 metabolite has been implicated in the inhibition and/or induction of multiple enzymes and transporters.[L12123,L12132]
来源:DrugBank