India — Canadian and American researchers have claimed to have developed an antiviral drug that they say is the “most potent” yet in countering the Covid-19 virus’s variants of concern (VOCs).
The drug called N-0385 “blocks the Sars-CoV-2 virus from entering human cells through its favoured cell gateways”, according to a release from Vancouver-based University of British Columbia (UBC).
A preprint version of the study on the new drug has been uploaded on website of the journal BioRXiv.
Francois Jean, a project lead and professor at UBC’s department of microbiology and immunology, said the researchers reported “a novel and highly potent small-molecule drug called N-0385 that acts as the most effective entry inhibitor to date”.
He said the researchers demonstrated that the new drug is “broadly protective against infection and mortality in mice, and believe N-0385 has potential as a viable early treatment option against emerging Sars-CoV-2 VOCs”.
The effect of the drug was studied on the B.117 and B.1.351 variants that were first detected in the UK and South Africa, respectively.
Jean told HT over email that his team is ready to test the drug against other VOCs, including “P.1, [first] identified in Brazil, and B.1.617.2 and other sub-clades [first] identified in India”.
Explaining the mechanism of the drug, Jean said it blocks “TMPRSS2, an enzyme responsible for cutting and priming the viral spike protein so that it can attach and fuse with the host cell’s membrane, and release the virus’s genetic material”.
That “cutting” of the viral spike protein is “important for the fusion step between the virions (virus particles) and the host cell’s membrane. The fusion event permits the release of the virus’s genetic material into the targeted cells”, Jean elaborated.
He believes the drug will also work against the coronavirus variant first detected in India, saying, “We speculate that the efficacy of N-0385 against B.1.617.2 would not be readily compromised, since no mutations in the TMPRSS2 cleavage site have been reported for B.1.617.2.”
Jean said that “viable treatments for VOCs are urgently needed as they carry mutations in the virus spike protein that allow them to speasily, and cause more serious illness. VOCs may also be more resistant to antibodies produced by vaccines”.
Multiple institutes were associated in developing the drug, including researchers at Universite de Sherbrooke in Quebec and US-based Cornell University.
While VOCs have contributed to the ongoing coronavirus crisis in India, they now “represent a majority of Covid-19 cases in Canada”, according to a statement from Canada’s Chief Public Health Officer, Theresa Tam.
She said as of May 14, the B.1.617 variant, including three currently defined sub-lineages, have been identified in nine provinces and territories.