Switching from intravenous to subcutaneous vedolizumab maintenance treatment in patients with inflammatory bowel disease followed by therapeutic drug monitoring.

OBJECTIVE: Vedolizumab (VDZ) for subcutaneous (SC) administration has recently become available. We aimed to assess feasibility, safety and clinical outcome when switching from intravenous (IV) to SC VDZ maintenance treatment in a real world cohort of patients with inflammatory bowel disease (IBD) followed by therapeutic drug monitoring (TDM). METHODS: Eligible IBD patients were switched from IV to SC treatment and assessed six months prior to switch, at baseline and six, twelve and twenty-six weeks after switch. Primary outcome was proportion of patients on SC treatment after 26 weeks. Secondary outcomes included adverse events (AEs), clinical disease activity, biochemical markers, treatment interval, serum-VDZ (s-VDZ), preferred route of administration and health-related quality of life. RESULTS: In total, 108 patients were switched. After 26 weeks, 100 patients (92.6%) were still on SC treatment and median s-VDZ was 47.6 mg/L (IQR 41.3 - 54.6). The most frequent AE was injection site reaction (ISR), reported by 20 patients (18.5%). There were no clinically significant changes in disease activity, biochemical markers and quality of life. The proportion of patients preferring SC administration increased from 28.0% before switch to 59.4% after 26 weeks (p < 0.001). CONCLUSIONS: Nine out of ten patients still received SC treatment after 26 weeks. No change in disease activity occurred, and levels of serum VDZ increased. Although almost one fifth of patients experienced ISRs, a higher proportion favored SC administration at 26 weeks. This study demonstrates that SC maintenance treatment is a safe and feasible alternative to IV treatment.

Subcutaneous Vedolizumab Treatment in a Real-World Inflammatory Bowel Disease Cohort Switched From Intravenous Vedolizumab: Eighteen-Month Prospective Follow-up Study.

Background: Vedolizumab has since 2021 been available as a subcutaneous formulation. We aimed to assess 18-month drug persistence and possible predictive factors associated with discontinuation, safety, serum drug profile, drug dosing, and disease activity in a real-world cohort of patients with inflammatory bowel disease switched from intravenous to subcutaneous vedolizumab maintenance treatment. Methods: Eligible patients were switched to subcutaneous vedolizumab and followed for 18 months or until discontinuation of subcutaneous treatment. Data on preferred route of administration, adverse events, drug dosing, serum-vedolizumab, disease activity, fecal calprotectin, and C-reactive protein were collected. Persistence was described using Kaplan-Meier analysis. The impact of clinical and biochemical variables on persistence was analyzed with Cox proportional hazard models. Results: We included 108 patients, and the estimated 18-month drug persistence was 73.6% (95% CI [64.2-80.1]). Patients in clinical remission at switch were less likely to discontinue SC treatment (HR = 0.34, 95% CI [0.16-0.73], P = .006), and patients favoring intravenous treatment at switch were almost 3 times more likely to discontinue (HR = 2.78, 95% CI [1.31-5.90], P = .008). Four patients discontinued subcutaneous vedolizumab due to injection site reactions. At 18 months, 88% of patients administered subcutaneous vedolizumab with an interval of ≥ 14 days, and serum-vedolizumab was 39.1 mg/L. Disease activity was stable during follow-up. Conclusions: Three of the four patients remained on subcutaneous vedolizumab after 18 months, a large proportion received treatment at standard dosing intervals, and disease activity remained stable. This indicates that switching from intravenous to subcutaneous vedolizumab treatment is convenient and safe.