Risk of Cancers According to the Use of Biological Agents in Patients With Radiographic Axial Spondyloarthritis: A Nationwide Population-Based Cohort Study.

Objective: As the duration of use of biological disease-modifying antirheumatic drugs (bDMARDs) in patients with radiographic axial spondyloarthritis (r-axSpA) accumulates over time, long-term real-world safety data on cancer risk are needed. This study assessed the association between tumor necrosis factor inhibitors (TNFis) and interleukin 17 inhibitors (IL-17is) exposures and cancer risk in patients with r-axSpA.

Methods: From the Korean nationwide database, we assembled 41,889 patients without prior history of cancer who were diagnosed with r-axSpA from 2010 onwards. Patients were followed up through 2021. Multivariable time-varying Cox models were performed to estimate the adjusted hazards ratios (aHRs) and 95% confidence intervals (CIs) of (1) overall cancers and (2) cancer subtypes according to TNFis exposure versus bDMARDs nonexposure, IL-17is exposure versus bDMARDs nonexposure, and IL-17is exposure versus TNFis exposure.

Results: The incident rates of overall cancers during bDMARDs nonexposure, TNFis exposure, and IL-17is exposure were 53.8, 37.6, and 67.3 per 10,000 person-years, respectively. TNFis exposure versus bDMARDs nonexposure was not associated with an increased risk of overall cancers (aHR = 0.9, 95% CI = 0.8-1.1). IL-17is exposure was not associated with an increased risk of overall cancers compared with bDMARDs nonexposure (aHR = 1.2, 95% CI = 0.5-3.0) or TNFis exposure (aHR = 1.3, 95% CI = 0.6-3.3). Similarly, no significant associations were observed between bDMARDs exposures and the risk of cancer subtypes.

Conclusions: In patients with r-axSpA, there was no evidence of increased cancer risk with TNFis and IL-17is exposures compared with bDMARDs nonexposure, suggesting that the use of bDMARDs is safe with respect to cancer risk in patients with r-axSpA.