Comparison of tocilizumab intravenously vs. tocilizumab subcutaneously vs. sarilumab (anti-interleukin 6 receptor α monoclonal antibody) subcutaneously vs. standard of care in patients with COVID-19. Open-label RCT (NCT04322773, not yet recruiting). Primary endpoint: time to independence from supplementary oxygen therapy (follow-up 28 days).