Introduction

Vedolizumab (VDZ) is an anti α4β7 integrin antibody therapy that inhibits migration of T-lymphocytes to the gastrointestinal epithelium through mucosal addressin cell adhesion receptor^1. As a licensed treatment for inflammatory bowel disease (IBD), it is now available as a subcutaneous (SC) formulation. The efficacy and safety of SC VDZ was comparable to intravenous (IV) therapy in two randomised controlled trials (VISIBLE 1 and 2) in ulcerative colitis (UC)² and Crohn disease (CD)². SC biologic preparations offer patients flexibility to self-administer therapy and reduce hospital visits.

Aims & Methods

Objective is to evaluate the efficacy of SC to IV VDZ in IBD and to assess impact on costs.
Patients receiving IV VDZ infusions at a single tertiary centre were assessed for eligibility to switch to SC formulation. Between February 2021 to February 2023, all patients switch and remaining on IV were included. Baseline data was collected with follow-up at 6 and 12 months. The primary outcome was maintenance of clinical remission, defined as HBI<4 for CD and SCCAI<3 for UC at 6 and 12 months. Secondary outcomes included serum CRP, faecal calprotectin (FCP), drug persistence at 6 and 12 months and potential savings calculated using the drug price and bed costs.
Results expressed as rates and odds ratio (OR) were analysed with GraphPad prism using one-way ANOVA, mixed-effect analyses (q value) and chi-squared test. Benjamini-Hochberg false discovery rate (FDR) adjustment was used for P value correction

Results

246 patients on IV VDZ were identified. 29 were not suitable to switch: 20/29 due to disease phenotype remained in the IV group, 11 patients on escalated dose regimen were excluded from both groups.
Of the 195 included patients, 175 were eligible to switch: 80/175 declined SC treatment due to preferences and continued IV therapy. In the SC switch group (n =95, 54%) median age was 54.5 years, 43% (n=41) were females, 63% (n=60) had UC, 37% (n=35) had CD. The commonest CD phenotype was ileal disease (N=15/35). Compared to the IV group (n =100, 51%) median age was 46 years, 42% (n=42) were females, 63% (n=63) had UC, 37% (n=37) had CD. The commonest CD phenotype was ileocolonic disease (N=11/37).
The primary outcomes are shown in Table 1 which demonstrated statistical significance in maintenance of remission with SC VDZ. The odd for remission with SC VDZ at 6 and 12 months were 1.1 [CI] (p0.7) and 3.6 [CI} (p0.006) at 12 months.
There were no statistically significant differences in CRP and FCP between baseline,6, or 12 months for the IV and SC groups. For CRP, 80% and 75% of patients maintained biochemical remission 6 and 12 months and for FCP 78% at 6 and 81% at 12 months.
Drug persistence for SC at 6 and 12 months were 93% and 87%, respectively. 4% (N=4) patients switched to a different drug due to loss of response, 8% (n=8) switched back to IV VDZ due to adverse events, issues with homecare or symptom control.
Based on this cohort of patients, an expected reduction of £ 72,010 per annum is likely to be achieved.

Conclusion

Transitioning patients from IV to SC VDZ was associated with low drug discontinuation rate. We observed higher remission rates at 12 compared with 6 months for SC group in comparison to patients who remained on IV VDZ. These findings should be used to encourage uptake of switching strategies.

References

1. Feagan, B. G., et al. Vedolizumab as induction and maintenance therapy for ulcerative colitis. N Engl J Med. 2013; 369(8): 699-710.
2. Sandbom WJ, Wolf D, D'haens G, et al. P510 Dose escalation of subcutaneous vedolizumab in patients With ulcerative colitis: A post hoc analysis of the VISIBLE trial data. Journal of Crohn’s and Colitis. 2020; 14 (Supplement_1): S442-S443

Disclosure

Nil