Variations in disease monitoring between patients with inflammatory bowel disease receiving intravenous and subcutaneous biological agents

Background and Aim: The availability of subcutaneous administration devices for biologics, in addition to intravenous administration, has influenced patients' and clinicians' preferences towards initiating or transitioning to subcutaneous administration, particularly during the coronavirus disease 2019 pandemic. Although subcutaneous administration improves patient convenience and reduces demands on infusion centers, we hypothesized that the reduction in health care contact associated with subcutaneous therapies may reduce the opportunities available for objective disease assessment in patients with inflammatory bowel disease (IBD). We aimed to compare the uptake of objective assessment of disease activity between patients receiving intravenous and subcutaneous biological therapy. Methods: Patients receiving maintenance infusion-based or subcutaneous biological therapy for IBD between September 2020 and February 2021 were identified from a prospectively maintained database at an Australian tertiary IBD center. Patients scheduled for review in the IBD clinic for a prescription of maintenance biological therapy during the follow-up period were included. Clinic records were reviewed to determine whether patients had undergone objective disease assessment, including biochemical investigation (C-reactive protein [CRP] and fecal calprotectin [FCP] testing) within the preceding 8 weeks, and/or endoscopic/imaging assessment within the preceding 6 months of clinic review. Frequency of objective disease assessment was compared between patients who received intravenous versus subcutaneous maintenance biological therapy. Results: A total of 307 patients were included: 195 receiving intravenous maintenance (infliximab, 135;vedolizumab, 60) and 112 receiving subcutaneous maintenance (adalimumab, 54;ustekinumab, 54;golimumab, 4). Patients who received intravenous biologics were more likely than the subcutaneous cohort to have had biochemical assessment in the form of CRP (90% vs 72%, P < 0.001) and FCP (54% vs 46%, P = 0.16) testing. Patients in the subcutaneous biologic cohort were more likely not to have had investigations completed before their clinical review (20% vs 4%, P < 0.001). There was no difference in the overall rates of complete objective disease assessment (CRP/FCP and endoscopy/imaging) between the intravenous and subcutaneous cohorts (28% vs 30%, P = 0.74). Conclusion: Patients receiving subcutaneous biological therapies in our cohort were less likely to have had objective disease monitoring than those receiving intravenous biologics before scheduled IBD clinic review. Route of biological administration may influence rates of uptake of objective disease activity assessment. Tools that safeguard against the disparity of monitoring uptake, including messaging prompts and patient-centric mobile applications, may help standardize the approach to objective disease assessment independent of the route of biological therapy administration.