SHELTON, CT / ACCESSWIRE / October 11, 2021 / NanoViricides, Inc. (NYSE American:NNVC) (the "Company"), a leader in the development of highly effective antiviral therapies based on a novel nanomedicines technology, announced today that its Pan-Coronavirus COVID-19 Drug Candidate NV-CoV-2 was found to be effective against SARS-CoV-2 in a standard cell culture pseudovirion assay, demonstrating that the drug indeed has broad-spectrum pan-coronavirus activity. This pan-coronavirus activity implies that the drug NV-CoV-2 should remain active in spite of evolution of variants of SARS-CoV-2 in the field, a highly sought-after characteristic to combat the current global pandemic.
In this assay, both the drug candidate NV-CoV-2 and a positive control antibody specific to the Spike antigen S1 of the SARS-CoV-2 virus suppressed the infection by the SARS-CoV-2-pseudovirions in cell culture studies to virtually the same baseline levels.
We have now demonstrated that NV-CoV-2 is highly effective in cell cultures against SARS-CoV-2, human coronavirus NL-63, and human coronavirus 229E, all very different human coronaviruses. These results imply that the drug will remain active in spite of novel variants of SARS-CoV-2 evolution in the field, and indeed demonstrate the pan-coronavirus activity of our clinical drug candidate NV-CoV-2.
Additionally, the pseudovirion study also showed that NV-CoV-2 neutralizes the virus particles themselves, outside of the cells, validating our design mechanism.
"We are now preparing submission documents to enable initiation of human clinical trials," commented Dr. Anil Diwan, Chairman and President of the Company, adding, "We believe that NV-CoV-2 may help end the pandemic if it is shown to be effective in human clinical trials."
A strong SARS-CoV-2 infection inhibition activity of NV-CoV-2 was observed in this pseudovirion study. Pseudovirion assay is a standard method for evaluating virus entry-inhibitors in BSL2 laboratories and is primarily used for viruses that would otherwise require high security BSL3 or BSL4 laboratories. In this study, SARS-CoV-2-pseudovirion virus particles were made that carry a green fluorescent protein (GFP) producer mRNA inside, and use the SARS-CoV-2 S1 protein on their surface to bind to ACE2 receptor protein on cells. They were incubated with NV-CoV-2 (test article), or a known neutralizing antibody (positive control), or just the vehicle buffer (negative control). Then these solutions were separately used to infect ACE2 positive cells and the cultures were incubated. Only the infected cells produced GFP and were visualized by green fluorescence in microscopy. In this well-known assay, NV-CoV-2 was as effective as the neutralizing antibody in reducing the virus infection. This study demonstrates that NV-CoV-2 attacks the SARS-CoV-2 pseudovirion particles and renders them incapable of binding to the ACE2 positive cells.
A "pseudovirion" is a virus particle made of a BSL-2 virus shell, but with its original cell-binding protein replaced by the cell binding protein of a BSL3 or BSL4 virus, in this case, the S1 antigen of SARS-CoV-2. Additionally, the pseudovirion particle contains an mRNA that is packaged like the original virus, except that the mRNA is edited and redesigned so that it cannot produce infectious virus particles. In our study, this mRNA allowed expression and production of the green fluorescent protein (GFP) enabling visual detection of the infected cells (green) in microscopy.