New Flu Therapy Potentially Effective Against COVID-19

A new therapy developed for the influenza virus has been put forward as potential protection against other viral infections, including the coronavirus disease 2019 (COVID-19). The new therapy was developed by scientists at Purdue University and implements a multidrug approach.

The study, published in Nature Communications, synthesized a bifunctional small molecule by uniting zanamivir and dinitrophenyl (DNP). Zanamivir is a neuraminidase inhibitor, which works by blocking the functioning of viral neuraminidases by preventing the virus’s reproduction in a host cell. DNP is a highly immunogenic hapten, a small molecule which stimulates the production of antibodies.

The conjugation of the two, named zan-DNP, specifically targets surfaces of free viruses, as well as viral infected cells. The research demonstrated that zan-DNP lead to a simultaneous inhibition of both virus release and immune-mediated elimination of virus-infected cells. A potent elimination of advanced infections, containing a very high viral load occurred in mice. Another highlight of the study is that since zan-DNP appears to be so potent, it would not require the ability to predict the viral strains potentially emerging in a coming flu season.

"We chose to start our tests with influenza virus because the results can often be applied to other enveloped viruses," Philip S. Low, the Purdue Ralph C. Corley Distinguished Professor of Chemistry said. "Our lab tests show that our process works in influenza infected mice that are inoculated with 100 times the lethal dose of virus."

With the flu season approaching closer every day, it is paramount to have readily available therapies for not only influenza and other viral infections, but COVID-19 as well. More than 2 million people are hospitalized every year for the flu in the United States, with 30,000 to 80,000 of them dying from it or related complications. This will only be exacerbated by the current COVID-19 pandemic.

"We target all of the antiviral drugs we develop specifically to virus-infected cells," Low said. "That way, we treat the diseased cells without harming healthy cells. We use this capability to deliver immune-activating drugs selectively into flu-infected cells. There is also the potential that this therapy will prove efficacious in people infected with COVID-19."