Study Highlights Antibody Development and Dosing Concerns in Older IBD Patients on Infliximab

A recent large-scale study published in Inflammatory Bowel Diseases highlights the increased risk of developing antibodies to infliximab (ATI) among older adults with inflammatory bowel disease (IBD) and underscores the need for proactive therapeutic strategies to optimize care in this population. The study analyzed 22,197 specimens from individuals with Crohn’s disease (CD) and ulcerative colitis (UC), focusing on infliximab dosing and antibody development.

Among the analyzed specimens, 13.6% showed the presence of ATI. Notably, the rate of ATI was higher in older adults (≥60 years), at 18.1%, compared to 15.0% in younger adults (<60 years) (P < .01). Older adults were less likely to receive escalated infliximab doses, with 38.4% receiving doses ≥10 mg/kg every 8 weeks compared to 49.7% of younger adults (P < .01).

When treated with lower infliximab doses (<10 mg/kg every 8 weeks), older adults had a higher likelihood of developing ATI (22.8% vs. 16.2%; P < .01). However, similar ATI rates were observed between age groups when higher doses (≥10 mg/kg every 8 weeks) were used, suggesting a dose-dependent effect on antibody development.

Multivariable analysis confirmed age ≥60 years (adjusted odds ratio [OR], 1.35; 95% CI, 1.20-1.51), lower infliximab doses (adjusted OR, 1.89; 95% CI, 1.85-2.04), and UC (adjusted OR, 1.44; 95% CI, 1.33-1.57) as independent predictors of ATI development.

The study underscores the importance of appropriate dosing strategies for older adults with IBD. While lower doses of infliximab may reduce concerns about adverse events, they appear to increase the risk of ATI, potentially compromising treatment efficacy. "Older adults were significantly more likely to develop ATI and less likely to receive escalated doses of IFX as compared with younger individuals with IBD," the authors note.

Proactive drug monitoring and consideration of combination therapy with immunomodulators may mitigate the risk of ATI.

Reference
Faye AS, Lee KE, Hudesman D, Dervieux T. Older adults with inflammatory bowel disease are at higher risk of developing antibodies to infliximab. Inflamm Bowel Dis. 2024;30(12):2509-2511. doi:10.1093/ibd/izad305