Postoperative Ustekinumab Drug Levels and Disease Activity in Patients with Crohn’s

Abstract

Aims This study investigated how post-operative ustekinumab levels relate to surgery type, endoscopic, biochemical, and clinical outcomes in patients with Crohn’s Disease. Methods A retrospective study of Crohn’s Disease patients with an operation related to Crohn’s Disease between 2016–2022. Patients were included if they had an ustekinumab trough level within two years post-operatively. Patients were separated into groups based on whether their ustekinumab trough levels were adequate, defined as ≥ 4µg/mL, or suboptimal < 4µg/mL. A subset of patients with ustekinumab levels taken within two years both before and after surgery was compared to non-surgical treatment escalated controls outside the initial patient set. Harvey-Bradshaw index was used to evaluate clinical disease activity. Rutgeert’s and Simple Endoscopic Score for Crohn’s Disease were used to evaluate endoscopic disease activity. C-reactive protein and fecal calprotectin values were collected to evaluate the molecular inflammatory disease state. CBC data was used to evaluate anemia. Results 44 patients were identified that had ustekinumab levels after Crohn’s Disease related surgery. 13 of these patients had pre-operative levels and were compared to 26 non-surgical treatment escalated controls. Lower clinical disease activity was seen overall and specifically in ileocecal resection for patients with adequate post-operative ustekinumab levels. No relationship between ustekinumab levels and endoscopic disease activity post-operatively was found. Adequate levels of ustekinumab post-operatively yielded lower risk of anemia. Surgery itself did not have an impact on ustekinumab levels. Conclusions This study provided new insights into how post-operative ustekinumab levels impact several factors in patients having undergone Crohn’s Disease related surgery.