Impact of fluctuating antibodies to infliximab

Impact of fluctuating antibodies to infliximab

February 8, 2022

Issue 03

Clinical Question

Do intermittent anti-TNF antibodies affect outcomes in patients with IBD?

Editor’s Bottom Line

Transient anti-drug antibodies do not appear to impact the efficacy of infliximab. Larger studies would help to confirm this finding.


Awadie H, Waterman M. Intermittent Appearance of Antibodies to Infliximab is not Associated with Reduced Efficacy in Patients with Inflammatory Bowel Diseases. J Clin Gastroenterol. 2022;56(1):e47-e51;


Up to 60% of patients receiving infliximab develop antibodies to infliximab (ATI). To determine the impact of ATI formation on IBD treatment response, researchers in Israel prospectively tracked infliximab trough levels and ATI in 48 patients with IBD receiving maintenance infliximab therapy for a mean of 23 months. The authors collected at least three serum samples per patient, who were classified as having either sustained negative ATI levels (<1 µg/mL for all samples) or fluctuating ATI levels, with at least one sample showing >1 µg/mL ATI.

Findings revealed that 25 patients had sustained negative ATI levels and 23 had fluctuating ATI levels. Rates of clinical response were similar between the fluctuating and low ATI groups (64% vs. 76%, respectively), both for ulcerative colitis (33% vs. 40%) and Crohn’s disease (76% vs. 100%).

The sustained low ATI and fluctuating ATI groups did not differ by IBD subtype, disease duration, use of concomitant immunomodulators or infliximab therapy duration. There were no significant differences between the groups in the levels of inflammatory biomarkers, specifically serum albumin (mean 4.2 vs. 3.9 g/dL for sustained negative ATI vs. fluctuating ATI, respectively) and serum C-reactive protein (mean 9.4 vs. 8.5 mg/dL). The two groups also did not differ in trough serum infliximab levels (mean 3.3 vs. 4.6 µg/mL).


Study Design: Prospective cohort

Funding: Not disclosed

Allocation: None

Setting: Single center

Level of Evidence: 2b