Studies of patients transitioning from tumor necrosis factor-α inhibitor originator to a biosimilar reported that about 8% of such patients retransitioned. Retransitioning was defined as switching from the originator to a biosimilar and back to the originator.

The following factors might result in fewer patients retransitioning: only transitioning patients with stable disease; not actively offering patients the option to retransition if they are dissatisfied with the biosimilar; and including extra laboratory monitoring as part of the biosimilar implementation strategy.