Researchers with the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development have revealed a potential new promising experimental drug for COVID-19. The study was released in Science.
Named TEMPOL, researchers focused on an enzyme called RNA replicase.
“Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of coronavirus disease 2019 (COVID-19), uses an RNA-dependent RNA polymerase (RdRp) for the replication of its genome and the transcription of its genes,” according to researchers.
“We found that the catalytic subunit of the RdRp, nsp12, ligates two iron-sulfur metal cofactors in sites that were modeled as zinc centers in the available cryo-electron microscopy structures of the RdRp complex.”
“These metal binding sites are essential for replication and for interaction with the viral helicase. Oxidation of the clusters by the stable nitroxide TEMPOL caused their disassembly, potently inhibited the RdRp, and blocked SARS-CoV-2 replication in cell culture. These iron-sulfur clusters thus serve as cofactors for the SARS-CoV-2 RdRp and are targets for therapy of COVID-19,” researchers also found.
In spite of the findings, clinical studies are necessary to establish the drug’s potential effectiveness in patients.
“Given TEMPOL’s safety profile and the dosage considered therapeutic in our study, we are hopeful. However, clinical studies are needed to determine if the drug is effective in patients, particularly early in the disease course when the virus begins to replicate,” said one author of the study in a press release.
