Discovery of potent SARS-CoV-2 nsp3 macrodomain inhibitors uncovers lack of translation to cellular antiviral response

作者：Alpha A. Lee, Isabelle Amick, J.C. Aschenbrenner, Haim Barr, Jared Benjamin, Alexander Brandis, Galit Cohen, Randy Diaz-Tapia, Shirly Duberstein, Jessica Dixon, David Cousins, M. Fairhead, D. Fearon, James Frick, James Gayvert, André S. Godoy, Ed J. Griffin, K. Huber, L. Koekemoer, Noa Lahav, Peter Marples, Briana L McGovern, Tevie Mehlman, Matthew C. Robinson, Usha Singh, Tamás Szommer, Charles W.E. Tomlinson, Thomas R. Vargo, F. von Delft, Si-Yi Wang, Kris M. White, Eleanor C Williams, Max Winokan · 发表于：bioRxiv (Cold Spring Harbor Laboratory) · 年份：2024 · DOI：10.1101/2024.08.19.608619 · 被引用次数：9 · 研究领域：interferon and immune responses、SARS-CoV-2 and COVID-19 Research、Viral Infections and Immunology Research

A strategy for pandemic preparedness is the development of antivirals against a wide set of viral targets with complementary mechanisms of action. SARS-CoV-2 nsp3-mac1 is a viral macrodomain with ADP-ribosylhydrolase activity, which counteracts host immune response. Targeting the virus' immunomodulatory functionality offers a differentiated strategy to inhibit SARS-CoV-2 compared to approved therapeutics, which target viral replication directly. Here we report a fragment-based lead generation campaign guided by computational approaches. We discover tool compounds which inhibit nsp3-mac1 activity at low nanomolar concentrations, and with responsive structure-activity relationships, high selectivity, and drug-like properties. Using our inhibitors, we show that inhibition of nsp3-mac1 increases ADP-ribosylation, but surprisingly does not translate to demonstrable antiviral activity in cell culture and iPSC-derived pneumocyte models. Further, no synergistic activity is observed in combination with interferon gamma, a main protease inhibitor, nor a papain-like protease inhibitor. Our results question the extent to which targeting modulation of innate immunity-driven ADP-ribosylation can influence SARS-CoV-2 replication. Moreover, these findings suggest that nsp3-mac1 might not be a suitable target for antiviral therapeutics development.