Subcutaneous Infliximab Therapy Efficacious for Inflammatory Bowel Disease

ibs, diarrhea, stomach ache
Researchers assessed the efficacy of subcutaneous vs intravenous infliximab among patients with inflammatory bowel diseases.

Switching infliximab therapy from intravenous (IV) to subcutaneous is safe, well-accepted, and leads to low risk for relapse among patients with inflammatory bowel disease (IBD), according to findings in Clinical Gastroenterology and Hepatology.

Researchers conducted a multicenter, observational study, called REMSWITCH, at 3 IBD referral centers. Study participants (N=133) were switched from an IV infliximab treatment regimen to a subcutaneous dose of 120 mg every other week, regardless of previous IV dose. Baseline was defined as the next theoretical date of the IV infusion.

This study included patients with Crohn disease (n=96) and ulcerative colitis (n=37) in steroid-free clinical remission with IV infliximab (partial Mayo score of ≤2 or Harvey-Bradshaw index ≤4). The average age of study participants was 39.3±15.5 years, and 54.1% were women.

Patients were grouped according to their IV infliximab treatment regimens: 5 mg/kg every 8 weeks (44.4%), 10 mg/kg every 8 weeks (30.8%), 10 mg/kg every 6 weeks (13.5%), and 10 mg/kg every 4 weeks (11.3%). Of these patients, 25.6% were receiving concomitant immunosuppressive therapy.

Study authors observed the change in infliximab serum levels from baseline to the first visit after switching and categorized findings into groups: increased (increase >1 μg/mL), stable (variation ≤±1 μg/mL), and reduced (decrease >1 μg/mL) levels. Relapses were defined as fecal calprotectin increases of at least 150 μg/g compared with baseline or clinical recurrences requiring treatment changes.

Rates of relapse 4 to 8 weeks after switching therapy were 6.7%, 7.3%, 16.7%, and 33.3% (P <.001) for patients previously treated with 5 mg/kg every 8 weeks, 10 mg/kg every 8 weeks, 10 mg/kg every 6 weeks, and 10 mg/kg every 4 weeks IV infliximab at baseline, respectively.

At 8 to 16 weeks, increases in relapse rates were seen in patients who were treated with 5mg/kg every 8 weeks (10.2%) and 10 mg/kg every 4 weeks (60%). For weeks 16 to 25, an increase in relapse rate was observed in patients previously treated with 10mg/kg every 4 weeks (66.7%).

An IV maintenance regimen of 10 mg/kg every 4 weeks (odds ratio [OR], 12.423; 95% CI, 1.569-98.36; P =.017) and fecal calprotectin levels above 250 μg/g at baseline (OR, 5.426; 95% CI, 1.067-27.596; P =.042) were strongly associated with relapse.

Fecal calprotectin levels showed no significant increases following the switch from IV to subcutaneous infliximab.

Patients who had reduced (41.7%) or stable (36.8%) serum levels of infliximab were more likely to experience relapse compared with those with increased serum levels (12.7%)(P =.02 and P =.019, respectively).

Limitations of this study include a small sample size and short follow-up times.

“Switching from intravenous to subcutaneous IFX [infliximab] 120 mg every two weeks is feasible, safe and well-accepted leading to a low risk of relapse in patients with IBD including those with escalated intravenous doses. However, patients receiving 10mg/kg/4weeks should be switched to higher SC [subcutaneous] dose (240 mg every two weeks) due to a high risk of relapse in this specific subgroup,” the study authors noted.

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Buisson A, Nachury M, Reymond M, et al. Effectiveness of switching from intravenous to subcutaneous infliximab in patients with inflammatory bowel diseases: the REMSWITCH study. Clin Gastroenterol Hepatol. Published online August 17, 2022. doi:10.1016/j.cgh.2022.08.011