On Mar. 16, 2020, Sanofi and Regeneron Pharma announced they have started a clinical program evaluating Kevzara (sarilumab) in patients hospitalized with severe COVID-19. Kevzara is a fully-human monoclonal antibody that inhibits the interleukin-6 (IL-6) pathway by binding and blocking the IL-6 receptor.

IL-6 may play a role in driving the overactive inflammatory response in the lungs of patients who are severely or critically ill with COVID-19 infection. The role of IL-6 is supported by preliminary data from a single-arm study in China using another IL-6 receptor antibody.