Tocilizumab Failed to Reduce Mortality in Severe COVID-19 Patients: Results from a Randomized Controlled Clinical Trial.

The severe coronavirus disease 2019 (COVID-19) is associated with increased levels of blood interleukin (IL)-6. Therefore, it is hypothesized that modulating the levels or effects of IL-6  could diminish airway inflammation and alter the course of COVID-19. We conducted a controlled, randomized, double-blind clinical trial on hospitalized patients with severe COVID-19 in Iran.