Leritrelvir Shows Enhanced Activity Against Drug-Resistant SARS-CoV-2 Variants, Study Finds
A new study demonstrates that leritrelvir, an antiviral drug approved in China, maintains stronger inhibitory activity against drug-resistant variants of the SARS-CoV-2 main protease compared to nirmatrelvir (used in Paxlovid). The research used biochemical, structural, and cellular analyses to show that leritrelvir binding restores the dimerization of protease mutants that have developed resistance to current treatments. The findings suggest leritrelvir could be a more effective treatment option as the virus continues to evolve resistance to existing antivirals.
Researchers evaluated leritrelvir's effectiveness against multiple drug-resistant variants of the SARS-CoV-2 main protease (Mpro), which is a critical target for COVID-19 antiviral development. The study tested the drug against 12 resistance-associated mutations and found that leritrelvir retained stronger inhibitory activity than nirmatrelvir against most resistant mutants. A key mechanism identified was that many resistance mutations cause the protease to dissociate from its dimer form, reducing drug binding; however, leritrelvir's tighter binding restores this dimerization. Sixteen crystal structures revealed how leritrelvir re-establishes critical dimer-interface interactions that resistance mutations had disrupted. Cellular assays confirmed leritrelvir's superior antiviral efficacy, suggesting it could serve as a more durable treatment option as SARS-CoV-2 continues to develop resistance to current therapies.
What's missing
The study does not discuss the clinical availability or regulatory status of leritrelvir outside China, potential limitations in the panel of mutations tested, or how findings might translate to real-world clinical outcomes with circulating variants.
What different sources said
- bioRxivCenter
Enhanced Target Binding by Leritrelvir Restores Dimerization of Mpro Mutants and Mitigates Drug Resistance
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