Infusion-to-injection infliximab switch safe, helps lower risk of IBD relapse for some patients

Switching from intravenous to subcutaneous infliximab appears to be safe and well-accepted, resulting in a reduced risk of relapse in some inflammatory bowel disease (IBD) patients, according to data from the REMSWITCH study.

REMSWITCH included 184 IBD patients in clinical remission (partial Mayo score ≤2 or Harvey-Bradshaw index ≤4) who were eligible to switch to a unique dose of subcutaneous infliximab (120 mg every other week [eow]). Researchers recorded pharmacological and biological data at baseline, visit 1 (4–8 weeks after switch), visit 2 (8–16 weeks after switch), and visit 3 (16–24 weeks after switch).

Of the patients, 133 (72.3 percent) agreed to switch to subcutaneous infliximab. Relapse, which was defined as clinical relapse or faecal calprotectin increase of ≥150 μg/g from baseline, occurred in 10.2 percent (6/59) of patients receiving 5mg/kg/8 weeks, 7.3 percent (3/38) of those receiving 10 mg/kg/8 weeks, 16.7 percent (3/18) of those receiving 10mg/kg/6 weeks, and 66.7 percent (10/15) of those receiving 10mg/kg/4 weeks (p<0.001).

Following dose escalation to 240 mg eow, clinical remission was recaptured in 93.3 percent of patients. Moreover, there was an increase seen in infliximab serum levels after the switch (p<0.0001), except for patients receiving 10 mg/kg/4 weeks.

Multivariable regression analysis revealed that the risk of relapse was significantly associated with the 10mg/kg/4 weeks regimen (odds ratio [OR], 12.4, 95 percent confidence interval [CI], 1.6–98.4; p=0.017) and faecal calprotectin >250 μg/g at baseline (OR, 5.4, 95 percent CI, 1.1–27.6; p=0.042).

Patients with reduced (41.7 percent) or stable (36.8 percent) infliximab serum levels between baseline and visit 1 also had a higher risk of relapse compared with those who had increased serum levels (12.7 percent; p=0.020 and p=0.019, respectively).

Patients’ acceptability of treatment was improved by the switch (6.9 vs 8.6 on a 10-point scale; p<0.0001). None of the patients developed severe adverse events.