Long-Term Outcomes of Intravenous Ustekinumab Maintenance Treatment in Patients With Loss of Response to Subcutaneous Dosing

Abstract Background Ustekinumab (UST) is commonly used to treat Crohn’s disease and ulcerative colitis. However, some patients may experience diminishing response or require increased dosage. Intravenous (IV) UST maintenance is explored as a solution. Objectives We sought to evaluate IV UST maintenance effectiveness and safety in inflammatory bowel disease patients with partial or lost subcutaneous UST response. Methods This was a multicenter retrospective study of inflammatory bowel disease patients on IV UST maintenance. Clinical response and remission at weeks 12 and 52, defined as Harvey-Bradshaw Index ≤4 for Crohn’s disease or partial Mayo score ≤2 for ulcerative colitis. Objective markers reduction (fecal calprotectin, C-reactive protein), UST trough levels pre- and post-IV maintenance, and adverse events were assessed. Results A total of 59 patients were included. Clinical remission at weeks 12 and 52 achieved by 47.5% and 64.3% respectively. 96.6% continued IV UST at follow-up. UST serum levels quadrupled. No adverse events reported. Conclusions IV UST maintenance effectively sustained remission in most patients at 52 weeks.