Sarilumab is a human monoclonal antibody used against the IL-6 receptor. IL-6 receptors are cytokines, small proteins important in cell signaling, which are most abundant in the serum and synovial fluid of RA patients. These levels typically correlate with disease activity and joint destruction.

Data taken from the BLA for sarilumab and studies from the global SARIL-RA phase 3 programs showed that about 2500 adults who suffer from moderate-to-severe RA did not have a positive response to other treatments.

So far, the efficacy and safety of sarilumab has yet to be evaluated by authorities. The global clinical development program is currently evaluating the drug to see if it can be used as a monotherapy or in combination with disease modifying anti-rheumatic drugs.