Common anti-inflammatory drugs may help spread the virus

A new study shows an unforeseen and unpleasant side effect of common medications. They may contribute to the spread of viruses.

Medications are supposed to help us get rid of illnesses or at least alleviate their symptoms. So it is especially disappointing when medications, on the contrary, contribute to making us even sicker. Many medications can have side effects, but some are particularly serious.

Researchers from the Department of Clinical and Molecular Medicine at the Norwegian University of Science and Technology (NTNU) have discovered a surprising and potentially serious side effect of a class of anti-inflammatory drugs. These drugs help viruses spread more easily in the body.

Influenza, COVID-19 and other viruses spread more easily

Drugs that can make the body more vulnerable to viral infections are used quite widely. They are known as Janus kinase inhibitors, or JAK inhibitors.

Among the viruses that are more easily affected by these drugs are Rift Valley fever virus, influenza A, adenovirus, and SARS-CoV-2, the virus that causes COVID-19.

These are fairly serious viral infections that can be severe enough without the unforeseen “help” of medications.

Drugs used to treat autoimmune diseases and arthritis

In a new paper in the journal NAR Molecular Medicine, Prof. Denis Kainov and colleagues describe how drugs can contribute to viral infections.

JAK inhibitors are often prescribed for autoimmune diseases and inflammatory conditions such as rheumatoid arthritis. But they also weaken the body’s natural defenses against viruses.

Specifically, the drugs suppress an important immune signaling pathway that helps protect healthy cells from viral attacks.

Suppression of an important gene response against viruses

The researchers found that drugs such as baricitinib suppress genes that respond to viral infections.

“These genes play a critical role in the body’s response to viral infections,” said Alexander Janiewski, an NTNU researcher and co-author of the new work. – By stopping or slowing down this signaling pathway, JAK inhibitors remove the body’s antiviral shield. It then becomes easier for viruses to gain a foothold and spread.”

The researchers used advanced virology techniques, organoid technology and gene expression analysis. They examined lung, eye and brain cells, as well as lab-created mini-organoids.

Although JAK inhibitors are effective in treating inflammation, the new study shows that they may pose a hidden risk for patients with latent or active viral infections.

Useful information in drug development

The findings suggest that health care providers should be cautious when prescribing JAK inhibitors, especially during viral outbreaks.

However, the researchers note that this immunosuppressive effect can also be utilized in controlled settings, such as in vaccine development or antiviral drug screening.

The researchers hope to raise awareness among doctors and researchers about the effects of this class of drugs.

They recommend further research to better understand how to optimally use these drugs, especially during virus outbreaks or pandemics.