# Subcutaneous vedolizumab interval extension in inflammatory bowel disease patients: a case series

## TL;DR

This study shows that extending the injection interval of vedolizumab in IBD patients in remission is safe and effective, with no flare-ups and reduced side effects.

## Contribution

First real-world evidence on extending subcutaneous vedolizumab intervals in IBD patients.

## Key findings

- No flare-ups observed in nine IBD patients over 10 months after extending injection intervals.
- Biochemical parameters remained stable, and vedolizumab-induced side effects mostly resolved.
- Healthcare costs may be reduced by extending injection intervals.

## Abstract

Subcutaneous vedolizumab has demonstrated efficacy as a maintenance therapy in inflammatory bowel disease (IBD). However, data on the extension of subcutaneous vedolizumab injection intervals are lacking. Here, we present the first real-world data on subcutaneous vedolizumab interval extension in IBD patients. Nine patients (eight Crohn’s disease patients and one ulcerative colitis patient) were included in the study. At interval extension (at baseline), all patients were in clinical and biochemical remission and requested an extension of their 2-weekly injection intervals due to side effects potentially related to subcutaneous vedolizumab. Patients increased their intervals to 3, 4, or 5 weeks. During a median follow-up of 10.0 months (IQR 6.5–19.5), no flare-ups were observed. After 6 months, median biochemical parameters remained stable compared to baseline levels (fecal calprotectin 24.0 µg/g [IQR 10.0–43.0] versus 28.0 µg/g [IQR 15.0–54.0], p = 0.553; C-reactive protein 3.4 mg/L [IQR 1.4–4.2] versus 3.1 mg/L [IQR 0.7–4.9], p = 0.172), while vedolizumab serum concentrations significantly decreased (22.0 µg/mL [IQR 20.0–33.0] versus 40.0 µg/mL [IQR 28.3–45.0], p = 0.018). After interval extension, almost all suspected vedolizumab-induced side effects disappeared within 6 months. Lengthening subcutaneous vedolizumab intervals in IBD patients in clinical and biochemical remission appears to be both effective and safe, potentially leading to substantial reductions in healthcare expenses.

Extending subcutaneous vedolizumab injection intervals in patients with inflammatory bowel disease: a case series

We observed nine patients with inflammatory bowel disease who extended the time between injections of subcutaneous vedolizumab. All patients initially received subcutaneous vedolizumab every two weeks and were in clinical and biochemical remission. However, they wanted to extend the injection interval due to possible side effects. They gradually increased their injection intervals to 3, 4, or 5 weeks. Over a median follow-up of 10 months, none of the patients experienced a flare-up. After six months, clinical and biochemical parameters remained stable, while vedolizumab serum concentrations decreased. Side effects that may have been caused by vedolizumab mostly resolved within six months of extending the injection intervals. Lengthening the time between subcutaneous vedolizumab injections for patients in remission appears to be effective, safe, and may also reduce healthcare costs.