Study links JAK inhibitor drugs to easier viral spread
Scientists at the Norwegian University of Science and Technology (NTNU) have found that a widely used class of anti-inflammatory medications may make it easier for certain viruses to infect cells and spread throughout the body.
“We have found a surprising and potentially serious side effect of a class of anti-inflammatory drugs. They can help viruses spread more easily in the body,” says Denis Kainov, a professor at the Department of Clinical and Molecular Medicine at NTNU.
The medications belong to a class called Janus kinase inhibitors, or JAKs. They are widely prescribed to control inflammation, but their effects on the immune system may also leave the body more vulnerable to viral infections.
“Among the viruses that more easily affect the body with the help of these drugs are Rift Valley fever virus, influenza A, adenovirus and SARS-CoV-2, the virus that causes COVID-19,” Kainov says.
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In a new study published in NAR Molecular Medicine, Kainov and his colleagues investigated how JAK inhibitors influence the body’s ability to defend itself against viruses.
“JAK inhibitors are often prescribed for autoimmune diseases and inflammatory conditions such as rheumatoid arthritis,” says Erlend Ravlo, a PhD research fellow at NTNU and first author of the article.
“In particular, the drugs suppress an important immune signalling pathway that helps protect healthy cells from viral attacks,” Ravlo said.
Scientists discover how JAK inhibitors disrupt immune protection
The research team found that JAK inhibitors, including the medication baricitinib, can reduce the activity of genes involved in fighting viral infections.
“These genes play a crucial role in the body’s response to viral infections,” said Aleksandr Ianevski, an NTNU researcher and coauthor of the new paper.
To investigate these effects, the scientists combined advanced virology methods with gene expression analysis and organoid technology. Their experiments included cells from the lungs, eyes and brain, along with miniature organ models grown in the laboratory.
“Although JAK inhibitors are effective in the treatment of inflammation, this shows that they can pose a hidden risk for patients who have latent or active viral infections,” says Ravlo.
What the findings mean for patients and future treatments
The results highlight the importance of carefully considering the risks associated with JAK inhibitors, particularly when patients may already have a viral infection or when outbreaks are occurring. Researchers suggest that healthcare professionals should exercise caution when prescribing these medications during periods of increased viral transmission.
Under controlled laboratory conditions, the immune-suppressing effects may help scientists develop vaccines or evaluate potential antiviral medications.
“We recommend further studies to better understand how the drugs can be used optimally, especially during virus outbreaks or pandemics,” says Ianevski.
Professor Magnar Bjørås of the Department of Clinical and Molecular Medicine provided significant scientific expertise and secured most of the funding for the research. Additional financial support came from the Central Norway Regional Health Authority, the South-Eastern Norway Regional Health Authority, the Research Council of Norway and the Swedish Research Council.
