Effectiveness of Switching From Intravenous to Subcutaneous Infliximab in Patients With Inflammatory Bowel Diseases: the REMSWITCH Study

Abstract

Background and Aim

We assessed the effectiveness of switching from intravenous to subcutaneous infliximab in patients with inflammatory bowel diseases (IBD) treated with or without intensified intravenous regimen.

Methods

In this multicenter observational study, IBD patients in clinical remission (partial Mayo score ≤ 2 or Harvey-Bradshaw index ≤ 4) were switched to a unique dose of subcutaneous infliximab (120 mg eow). Pharmacological and biological data were collected at baseline, visit 1 (4-8 weeks post-switch), visit 2 (8-16 weeks post-switch) and visit 3 (16-24 weeks post-switch). Relapse was defined as clinical relapse or faecal calprotectin increase ≥ 150 μg/g compared to baseline.

Results

Among 184 eligible patients, 72.3% (133/184) agreed to switch to subcutaneous infliximab. At visit 3, a relapse occurred in 10.2% (6/59), 7.3% (3/38), 16.7% (3/18) and 66.7% (10/15) (p < 0.001) of patients receiving 5mg/kg/8weeks, 10 mg/kg/8weeks, 10mg/kg/6weeks, and 10mg/kg/4weeks, respectively. Dose escalation to 240mg eow, led to recapture clinical remission in 93.3% (14/15). Infliximab serum levels increased after the switch (p<0.0001) except for patients receiving 10 mg/kg/4 weeks. In multivariable analysis, 10mg/kg/4 weeks regimen (OR=12.4[1.6-98.4], p=0.017) and faecal calprotectin >250 μg/g at baseline (OR=5.4[1.1-27.6],p=0.042) had a higher risk of relapse as well as reduced (41.7%) or stable (36.8%) infliximab serum levels between baseline and visit 1 compared to increased serum levels (12.7%) (p=0.020 and p=0.019, respectively). Patients' acceptability (10 points-scale) was improved by the switch (6.9±1.6 vs 8.6±1.4; p<0.0001). No severe adverse event was reported.

Conclusions

Switching from intravenous to subcutaneous infliximab 120 mg eow is safe and well-accepted leading to a low risk of relapse in IBD patients except for those receiving 10mg/kg/4weeks requiring 240 mg eow.