Evaluation of the Switch From the Original Infliximab to Its Biosimilar in Daily Practice at Cochin Hospital

All patients managed in one of the departments of cochin Hospital who are receiving the original infliximab ( REMICADE®) from at least 4 months will be invited to continue to receive infliximab but using its biosimilar (INFLECTRA®)) at the same regimen (identical dose per infusion and interval between two infusions) than the previous one while receiving REMICADE®. The tolerability of the infusion will be recorded as well as the percentage of patients continuing INFLECTRA® after at least six months of its initiation. Moreover, the infliximab serum level will be evaluated after the last infusion of REMICADE® and after the third infusion of INFLECTRA®. At the same time, anti-drug antibodies will be tested. Finally for each of the underlying disease (e.g. rheumatoid arthritis, spondyloarthritis, Crohn's disease, uveitis,..), the maintenance of the efficacy of Infliximab will be evaluated according to the usual outcome measures of the activity of the disease