Japanese experts find effective treatment for severe COVID-19

Japanese researchers have identified an effective treatment for the deadly over-activation of the inflammatory response seen in many severe COVID-19 patients.

The COVID-19 pandemic has ravaged the world for months now. Fortunately, there may be a vaccine soon in the market with many hopeful candidates already in final stages of trials. Some experts are hopeful of getting one to the market by the end of the year and countries are planning mass vaccinations. However, till now, nobody has been able to identify a single drug that can help treat the disease. There are many existing drugs that scientists have looked into. But these work to treat part of the complications only. But an effective treatment is missing from the scene.

As countries around the world race to develop a vaccine for COVID-19 virus, Japanese researchers from the Osaka University in Japan have identified an effective treatment for the deadly over-activation of the inflammatory response seen in many severe COVID-19 patients. In a study, published in the journal PNAS, researchers are working to understand exactly how the virus causes the myriad of symptoms that seem to linger long after active viral infection.

No targeted immunotherapy yet for patients

Cytokines are a group of small proteins that can either enhance or inhibit our body's immune response to infection, trauma, and diseases such as cancer. One of their main roles is to stimulate inflammation, which initiates the healing process. The problem is, overstimulation of the inflammatory response has an array of harmful complications, ranging from asthma to severe autoimmune diseases, the team said. One such complication, called cytokine release syndrome (CRS), is seen in patients suffering a hyperimmune response to microbial infection or trauma and can lead to multiple organ failure and even death. Researchers say that despite knowing which cytokines are involved, there is still no specific immunotherapy for CRS and treatment is limited to supportive care.

Experts identify pro-inflammatory cytokine behind blood clots

According to researchers, to better understand the molecular mechanisms of CRS pathogenesis, they first studied the cytokine profiles of 91 patients diagnosed with CRS associated with bacterial sepsis, acute respiratory distress syndrome, or burns. Strikingly, patients from all three groups had elevated levels of pro-inflammatory cytokines IL-6, IL-8, IL-10, and MCP-10, as well as a protein called PAI-1, which causes small blood clots in vessels throughout the body, including the lungs. Importantly, increased PAI-1 levels are associated with more severe cases of pneumonia, a common cause of death among COVID-19 patients. Because IL-6 was positively associated with the levels of the other cytokines and PAI-1, the researchers concluded that IL-6 signalling is crucial for the development of CRS following infection or trauma, and may play a role in the pathogenesis of this disease.

Drug to block IL-6 signalling identified

Examination of cytokine profiles in severe COVID-19 patients revealed an increase in IL-6 early in the disease process, causing the release of PAI-1 from blood vessels. Interestingly, PAI-1 levels were significantly higher in those patients who suffered from a severe respiratory impediment. Most significantly though, when patients with severe complications were treated with a human monoclonal antibody-based drug called Actemra, which blocks IL-6 signalling, PAI-1 levels rapidly declined and severe disease symptoms were alleviated.

(With inputs from IANS)