Mass Balance of the Indoleamine 2,3‐Dioxygenase Inhibitor Navoximod (GDC-0919) in Rats and Dogs: Unexpected Cyanide Release from Imidazo[5,1-<i>a</i>]isoindole and Species Differences in Glucuronidation
作者:Shuai Wang、Shuguang Ma、Eugene Chen、Jing Wang、Hoa Le、Steven Paul Hanlon、Martin Binder、Wendy Lee、S. Cyrus Khojasteh、Laurent Salphati
DOI:10.1124/dmd.123.001289
日期:2023.7
humans (<6% and <1%). The novel cyanide release is proposed to occur via 4,5-epoxidation on the fused imidazole ring, leading to ring opening and rearrangement along with the release of cyanide. The decyanated metabolites were identified and confirmed by synthetic standards, which supported the proposed mechanism. In dogs, glucuronidation to M19 was the major clearance mechanism, representing 59% of the
Navoximod (GDC-0919) 是一种小分子吲哚胺 2,3-双加氧酶 1 (IDO1) 抑制剂,用于降低与癌症相关的 T 细胞免疫抑制。这项研究描述了在大鼠和狗单次口服剂量后 navoximod 的吸收、代谢和排泄 (AME) [ 14C]-navoximod。意外的硫氰酸盐代谢物 M1 和手性反转代谢物 M51 作为大鼠体内的主要循环代谢物被捕获,分别占 0-24 小时暴露的 30% 和 18%。这两种代谢物加在一起在狗和人类中的全身暴露量要低得多(<6% 和 <1%)。新的氰化物释放被认为是通过稠合咪唑环上的 4,5-环氧化作用发生的,导致开环和重排以及氰化物的释放。脱氰代谢物通过合成标准进行鉴定和确认,支持所提出的机制。在狗中,M19 的葡萄糖醛酸化是主要的清除机制,占胆管插管 (BDC) 狗胆汁中剂量的 59% 和完整狗尿液中剂量的 19%。此外,M19 还占狗循环中与药物相关的暴露量的