Identification of key metabolic enzymes involved in the activation of obeldesivir and remdesivir to the active triphosphate metabolite

作者：Yili Xu, Albert Liclican, Xiaofeng Zhao, Chen Chen, Joseph T. Ortega, Hsiu-Chun Chuang, Cameron Soulette, Subhra Chaudhuri, Jingyu Zhang, Ting Wang, Darius Babusis, Bruno Marchand, Kai-hui Sun, Ricardo Ramírez, Bin Ma, Arabinda Nayak, Liya Wang, Saurabh Menon, Jean-Philippe Belzile, Yurong Lai, Li Li, Richard L. MacKman, John P. Bilello, Tomáš Cihlář, Joy Y. Feng, Latesh Lad · 发表于：Antimicrobial Agents and Chemotherapy · 年份：2026 · DOI：10.1128/aac.00055-26 · 研究领域：Pharmacological Receptor Mechanisms and Effects、COVID-19 Clinical Research Studies、Enzyme function and inhibition

ABSTRACT Obeldesivir (GS-5245, ODV), an orally administered 5′-isobutyryl ester prodrug of GS-441524, has demonstrated anti-SARS-CoV-2 activity in preclinical and clinical settings. ODV is hydrolyzed in plasma to provide high systemic exposures of GS-441524, enabling the efficient intracellular formation of the bioactive 5′-triphosphate GS-443902, an ATP analog inhibiting the SARS-CoV-2 RNA-dependent RNA polymerases. Remdesivir (RDV), the first US FDA-approved antiviral treatment for COVID-19, is also activated to GS-443902. In this paper, we systematically profiled the human enzymes potentially involved in ODV and RDV activation using multiple approaches: (i) biochemical studies on the catalytic efficiency ( k cat / K m ); (ii) analysis of activation in single-gene knockout cells; and (iii) the antiviral activity assessment in single-gene knockout cells. Our results demonstrated that ODV hydrolysis to GS-441524 is catalyzed by carboxylesterase 1 and 2 with high efficiency. For the enzymes involved in the consecutive formation of 5′-mono-, di-, and tri-phosphates (MP, DP, and TP), adenosine kinase (ADK) likely plays a minor role in forming GS-441524-MP, suggesting the involvement of other phosphotransferases. This was further supported by cell-based single-gene ADK-knockout studies. In contrast, both biochemical and cell-based assay data strongly support adenylate kinase 2 as the key enzyme for the phosphorylation of GS-441524-MP, while nucleoside diphosphate kinase NM23-H2, ...