Introduction

Crohn’s disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of digestive tract, and anti-inflammatory drugs, such as vedolizumab, have central role in their treatment. Intravenous form of vedolizumab is approved for induction and maintenance of remission in patients with CD and UC. Recently, subcutaneous form of vedolizumab was approved as a maintenance therapy after the induction with, at least, two intravenous doses.

Aims & Methods

The aim of this study was to show how the switch from intravenous to subcutaneous vedolizumab in a real-life setting in inflammatory bowel disease (IBD) patients on stable maintenance therapy affects vedolizumab serum concentration and clinical outcomes. IBD patients treated with intravenous vedolizumab and planned to switch to subcutaneous vedolizumab at the Department of Gastroenterology and Hepatology in the University Hospital Centre Osijek were included in the study. Patients were in remission at the time of transition (based on clinical symptoms, fecal calprotectin level or endoscopy scores). Data on vedolizumab serum trough concentration and clinical outcomes (remission rate, fecal calprotectin level, clinical scores, hospitalization rate, rate of surgical procedures, change of therapy, and adverse events) were collected prior to and after the switch from intravenous to subcutaneous vedolizumab.

Results

In total, 31 patients, 17 with CD and 14 with UC, were included in final analysis. Median follow up was 12 months (interquartile range, IQR 9-12). Median duration of therapy with intravenous vedolizumab prior to switch was 14 months (IQR 6-32). Mean serum trough concentration of intravenous vedolizumab was significantly lower than mean serum trough concentration of subcutaneous vedolizumab (25.62 mg/L±14.29 vs. 34.93±14.59 mg/L; p=0.002). This rise in vedolizumab serum concentration after the switch to subcutaneous drug, was more evident in CD (Δ11.8 mg/L) than in UC (Δ5.79 mg/L) patients. There was no significant difference between fecal calprotectin level in all patients, as well as fecal calprotectin and Harvey–Bradshaw index in CD patients prior to or after the transition to subcutaneous vedolizumab. In UC patients, fecal calprotectin and Partial Mayo score were significantly higher (p= 0.011 and p=0.018, respectively) after the switch to subcutaneous vedolizumab, although this difference was not clinically significant. There was a significant difference in remission rate before and after the transition to subcutaneous vedolizumab in all patients (100% vs 71%; p=0.004), and in UC patients (100% vs. 57.1%; p=0.031). During the follow up, one (3.2%) CD patient was hospitalized and had a surgical procedure due to IBD. In 7 (22.6%) patients, the therapy was discontinued during the follow-up period with a median of 8 months. In all patients, therapy was discontinued due to loss of response. In total, 27 adverse events were reported by 17 patients, and the most common adverse event was COVID-19. One serious adverse event was reported (a patient was hospitalized for subileus).

Conclusion

Despite the rise in serum vedolizumab trough concentration after the switch from intravenous to subcutaneous vedolizumab, total remission rate was significantly lower in all patients and in the subgroup of UC patients. No new safety signals were observed in patients after the switch to subcutaneous vedolizumab.

Disclosure

Vlasta Oršić Frič has received speaker honoraria from Takeda, Janssen, Merck Sharp & Dohme, Sandoz, Ferring, Oktal Pharma, Abbvie, Viatris-Mylan and has been a member of advisory board for Janssen. Vladimir Borzan has received speaker honoraria from Takeda, Janssen, Sandoz, Merck Sharp & Dohme, Abbvie, Oktal Pharma, Viatris-Mylan, Ferring and has been a member of advisory board for Takeda, Sandoz, Abbvie, Viatris-Mylan, Merck Sharp & Dohme. Other authors declare no conflict of interest.