Two biomarkers of COVID-19 disease survival identified by researchers

Scientists have identified two markers of inflammation that they say can reliably predict the severity of COVID-19 cases and likelihood of survival, providing a foundation for a diagnostic platform and therapeutic targets.

The study was conducted at Mount Sinai Hospital and Mount Sinai School of Medicine, US. The researchers studied four cytokines that circulate in the blood and are commonly associated with infections. They found that two of them, IL-6 and TNF-α, were able to predict which patients were likely to develop more severe forms of COVID-19 and die.

The scientists established that the levels of IL-6 and TNF-α in serum, when measured at admission to the hospital, were elevated in patients who fared the worst, a finding that was independent of the patients’ other underlying medical conditions, demographics such as age and sex and other clinical biomarkers.

According to the researchers, the results from the tests showed that the risk of death in patients with elevated IL-6 or TNF-α was twofold or higher, even when considering other known risk factors. Scientists then validated their predictive model using samples from an additional cohort of 231 hospitalised COVID-19 patients.

The researchers suggest that these cytokines should be monitored in the treatment of COVID-19 patients to help select those who should enter clinical trials and receive specific drugs that can target them.

“We propose that serum IL-6 and TNF-α levels should be considered in the management and treatment of COVID-19 patients to stratify prospective clinical trials, guide resource allocation and inform therapeutic options,” said lead researcher Dr Sacha Gnjatic, Associate Director of the Human Immune Monitoring Center at Mount Sinai. “We also propose that patients with high IL-6 and TNF-α levels should be assessed for combinatorial blockade of pathogenic inflammation in this disease. Drugs blocking these cytokines are either US Food and Drug (FDA)-approved or in clinical trials.”

The researchers propose that these findings also call for the use of drugs targeting IL-6 and TNF-α by themselves or combined at the same time, to be tested for their potential benefit based on elevated starting levels.

The results were published in Nature Medicine.