Preliminary experience of maintenance treatment with intravenous ustekinumab as a rescue treatment for loss of response to subcutaneous doses.

It has been demonstrated that ustekinumab (UST) is effective as an induction and maintenance therapy in patients with Crohn's disease (CD). However, a significant number of patients experience an insufficient response or a secondary non-response. We report six cases from our center that underwent a rescue treatment by changing maintenance treatment to weight-adjusted intravenous UST, obtaining a subsequent clinical improvement.