Intestinal Research

Original Article

IBD

A real-world comparison of subcutaneous to intravenous administration of infliximab in patients with inflammatory bowel disease: Kwang Woo Kim, Hyoun Woo Kang, Seong-Joon Koh, Hyuk Yoon, Sihyun Kim, Yukyung Jun, Hyun Jung Lee, Jong Pil Im, Young Soo Park, Ji Won Kim, Joo Sung Kim, Seoul National University Inflammatory Bowel Disease Research Network (SIRN); Intest Res 2025;23(4):483-490. Published online June 23, 2025; DOI: https://doi.org/10.5217/ir.2025.00001

Abstract PDF Supplementary Material PubReader ePub: Background/Aims
We compared intravenous and subcutaneous infliximab (IFX) as treatment for inflammatory bowel disease (IBD).
Methods
This retrospective, multicenter, observational study enrolled patients treated with either intravenous or subcutaneous IFX. Sequential parameters were compared at baseline, 6 months, and 12 months following the initiation of treatment with either type of IFX. The primary outcome was the comparison of the IFX trough levels after 12 months of treatment.
Results
In total, 183 participants were included in this study. After 6 months, the subcutaneous group exhibited significant differences compared to the intravenous group; in terms of clinical disease activity (0% vs. 15%, P= 0.007) and IFX trough level (21.72 ± 8.71 μg/mL vs. 7.70 ± 16.65 μg/mL, P= 0.002). After 12 months, subcutaneous, as compared to intravenous, achieved improved clinical disease activity (0% vs. 15%, P= 0.044) and IFX trough level (20.41 ± 12.91 μg/mL vs. 7.06 ± 6.81 μg/mL, P< 0.001). Analyzing the sequential changes compared with baseline data within each group, we observed significant alterations in subcutaneous; 6 months fecal calprotectin (676.3 ± 976.6 μg/g vs. 253.9 ± 483.9 μg/g, P= 0.014), 6 months IFX trough level (7.00 ± 5.67 μg/mL vs. 18.44 ± 6.34 μg/mL, P= 0.026), and 12 months IFX trough level (7.00 ± 5.67 μg/mL vs. 21.33 ± 4.50 μg/mL, P= 0.034).
Conclusions
This study indicates the potential suitability of subcutaneous IFX as an alternative treatment option for IBD.