Calming the cytokine storm of COVID-19 through inhibition of JAK2/STAT3 signaling.

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the unprecedented COVID-19 pandemic, which has infected over 178 million people worldwide. Even with new vaccines, global herd immunity will not be reached soon. New cases and viral variants are being reported at an alarming rate. Effective antiviral treatment is urgently needed. Patients with severe COVID-19 suffer from life-threatening respiratory failure due to acute respiratory distress syndrome in their lungs, a leading cause of COVID-19 mortality. This lung hyper-inflammation is induced by virus-caused massive tissue damage that is associated with uncontrolled cytokine release, known as a cytokine storm, through JAK/STAT signaling pathways. Here, we review the FDA-approved JAK inhibitors that are being clinically evaluated and repurposed for the treatment of patients with severe COVID-19 by calming SARS-CoV-2 infection.