Hypersensitivity to IV Ustekinumab but Tolerance to Subcutaneous Ustekinumab in a Patient With Crohn's Disease

IL-23 Monoclonal Antibodies for IBD: So Many, So Different?

Interleukin [IL]-23 is a member of the IL-12 family of cytokines and has been implicated in multiple inflammatory disorders including psoriasis, psoriatic arthritis, and the inflammatory bowel diseases [IBDs]. Blockade of both IL-12 and IL-23 using an antibody that targets a shared subunit is highly effective in treating psoriasis, and recent data suggest similar efficacy in IBD with minimal adverse events. In this review, we summarise published data on the efficacy of anti-IL-12/23 therapies in IBD as well as emerging data on more selective anti-IL-23 specific therapies. Last, we discuss novel therapeutics under development which target the IL-23 pathway in unique ways and suggest that a biomarker-driven approach will soon guide clinicians to prescribe anti-IL-23 therapies to the patients most likely to respond to them.

Hypersensitivity Reaction to Ustekinumab in Pediatric and Young Adult Inflammatory Bowel Disease Patients: A Case Series

Ustekinumab (UST) is a human IgG1K monoclonal antibody that binds to the p40 receptor subunit bound by cytokines IL-12 and IL-23. It is indicated in both Crohn's disease and ulcerative colitis as a second-line agent. The safety and efficacy of UST in children and young adults has not been thoroughly studied. We report a case series of six pediatric patients and young adults who developed hypersensitivity reactions during intravenous infusion with UST. These reactions ranged from mild allergic reactions to anaphylaxis, with no detectable antibodies if tested. We hypothesize the reaction could be secondary to ethylenediaminetetraacetic acid, which is present solely in the intravenous preparation. Patients who experience hypersensitivity reactions during their UST infusion may safely receive subcutaneous preparations of UST, as demonstrated by some patients who received it based on physician discretion. Further investigation is required to establish the etiology of infusion reactions.

Immediate Infusion Reaction to Intravenous Ustekinumab in Three Crohn's Disease Patients: A Case Report and Review of the Literature

Recently, ustekinumab has been approved for the treatment of Crohn's disease and ulcerative colitis. Treatment is started with an intravenous induction dose, followed by a subcutaneous dosage. We present details of three patients with therapy-refractory Crohn's disease who experienced an immediate infusion reaction to intravenous administration of ustekinumab. In two of these patients a subsequent reaction to subcutaneous injections occurred. Clinical features and pathophysiology are discussed.