Treatment with antivirals like interferons has significantly improved virus clearance and reduced levels of inflammatory proteins in COVID-19 patients, according to a recent study published in the journal Frontiers in Immunology.
The study conducted among moderately infected COVID-19 patients at a hospital in Wuhan, China, showed that treatment with interferon (IFN)-α2b significantly reduced the duration of virus shedding in the upper respiratory tract. Likewise, the inflammatory proteins like interleukin (IL)-6 and C-reactive protein (CRP) were also reduced with the therapy.
“Interferons are our first line of defence against any and all viruses – but viruses such as coronaviruses have co-evolved to very specifically block an interferon response”, says lead author Dr Eleanor Fish of the Toronto General Hospital Research Institute & University of Toronto’s Department of Immunology.
The antiviral drug IFN-α2b is a recombinant form of the protein interferon alpha-2, a protein that in humans is encoded by the IFNA2 gene. The drug has been used for a wide range of indications, including viral infections and cancers.
The study evaluated 77 COVID infected individuals between January 16th and February 20th 2020. The patients were either treated with antivirals IFN-α2b,, or another broad-spectrum antiviral arbidol (ARB), or a combination of both IFN-α2b and ARB. Treatment via inhalation of IFN-α2b, alone or in combination with ARB, accelerated viral clearance compared to ARB treatment alone. The viral clearance was confirmed after two consecutive negative tests for the virus at least 24 hours apart, from throat swab samples.
The researchers demonstrated a significantly different rate of viral clearance for each treatment group and notably, IFN-α2b treatment accelerated viral clearance by approximately 7 days. The significant reduction in circulating levels of inflammatory markers with IFN-α2b supports the functional connection between viral infection and host end-organ damage by limiting the subsequent inflammatory response in the lungs of patients.
Based on the positive results from the teams previously conducted clinical study using interferons during the SARS outbreak of 2002 and 2003, the researchers decided to use the therapy which turned out to be favourable in COVID-19 cases as well.
“.. Our findings were that interferon treatment sped up the resolution of lung abnormalities in patients treated with interferon compared with those not treated with interferon” says Fish.
“Rather than developing a virus-specific antiviral for each new virus outbreak, I would argue that we should consider interferons as the ‘first responders’ in terms of treatment. “ he said in a statement.
However, in the current study, only moderate cases of COVID-19 was taken as none of the patients required intensive care or oxygen supplementation or intubation. The researchers look forward to developing a more randomized controlled clinical trial including a larger cohort of infected patients for treatment with interferon-alpha or a placebo to further advance the research.