Efficacy of Intravenous Ustekinumab Reinduction in Patients With Crohn’s Disease With a Loss of Response

Background/Aims: In patients receiving ustekinumab (UST) for treatment of Crohn's disease, there is no proven strategy to enhance or re-capture response. We assessed the utility of UST intravenous (IV) reinduction (~6 mg/kg) to achieve clinical, biochemical and endoscopic response or remission, in patients with partial or loss of response to UST maintenance therapy. Methods: A multicentre, retrospective cohort study was performed. Adults who received an IV reinduction dose of UST for either partial response or secondary loss of response to UST were assessed. The primary outcome was clinical remission off corticosteroids (Harvey Bradshaw Index <5), with biochemical response (defined as ≥ 50% decrease of CRP or FCP and/or endoscopic response (defined as a decrease in Simple Endoscopic Score-CD ≥ 50%). Secondary outcomes included clinical, biomarker and endoscopic response/remission, as well as safety. Results: Sixty-five patients (median age 38 years, 54.7% women) underwent IV UST reinduction between January 2017 and April 2019. Most patients (88.3%) were already on escalated maintenance dosing of UST 90 mg subcutaneous every 4 weeks. Clinical outcomes were assessed at a median of 14 weeks (IQR: 12-19) post-reinduction. The primary outcome of clinical remission off corticosteroids with biochemical and/or endoscopic response was achieved in 31.0% (n = 18). Pre-reinduction UST concentrations were ≥1 μg/mL in 88.6% (mean 3.2 ± 2.0 μg/mL). No serious adverse events were reported. Conclusions: UST IV reinduction can be effective in patients with Crohn's disease with partial or loss of response to UST maintenance therapy. Further studies evaluating this strategy are warranted.