# Incidence rates of tuberculosis and inflammatory bowel disease in patients with ankylosing spondylitis treated with biologics in Korea

## TL;DR

This study examines how often tuberculosis and inflammatory bowel disease occur in Korean patients with ankylosing spondylitis who use biologic treatments.

## Contribution

The study provides updated, real-world incidence rates of TB and IBD in Korean patients with AS treated with various biologics.

## Key findings

- TNF inhibitors like adalimumab and infliximab were linked to higher TB risk compared to no biologic use.
- Secukinumab showed no increased TB risk and IL-17 inhibitors had lower TB rates than TNF inhibitors.
- Biologics did not significantly increase the risk of IBD compared to no biologic use.

## Abstract

To describe the incidence rates of inflammatory bowel disease (IBD) and tuberculosis (TB) in Korean patients with ankylosing spondylitis receiving biologics.

Data from a Korean claims database between 2010 and 2021 was used to calculate crude incidence rates of TB and IBD using number of events and total patient-years (PYs).

Overall, 43 643 and 43 396 patients were included in TB and IBD cohorts, respectively. Exposure-adjusted incidence rates (EAIRs) of TB for non-exposure, TNF inhibitors (TNFis), and IL-17 inhibitors (IL-17is) were 0.14, 0.25 and 0.12 and of IBD were 0.18, 0.19 and 0.44 per 100 PYs, respectively. Incidence rates during biologic DMARD (bDMARD) non-exposure, adalimumab, etanercept, golimumab, infliximab, secukinumab and ixekizumab exposures for TB were 13.96, 27.79, 14.28, 21.19, 33.62, 12.74 and 0.00 and for IBD were 18.29, 19.98, 22.41, 18.85, 15.73, 44.99 and 0.00 per 10 000 PYs, respectively. Compared with bDMARD non-exposure, adalimumab, golimumab and infliximab exposures were associated with a significantly higher risk of TB. Etanercept and secukinumab exposure showed no significant increase in risk of TB. Compared with bDMARD non-exposure, exposure to biologics did not show a significant difference in risk of IBD.

EAIRs of TB and IBD with use of IL-17is in patients with AS were within anticipated low range. IL-17is had numerically lower incidence of TB, and numerically higher incidence of IBD compared with TNFis. Notably, secukinumab showed no increased risk of TB compared with bDMARD non-exposure. Neither TNFis nor IL-17is showed increased risk of IBD compared with bDMARD non-exposure.