Baraliakos X, Kruse S, Auteri SE, et al. - In this sample of axial spondyloarthritis (axSpA) patients assessed over 4 years, the risk of long-term fat lesion (FL) development in the spine was shown to be mitigated by early and sustained suppression of inflammation.

• This is a post-hoc analysis from RAPID-axSpA, to determine if TNFi treatment over 4 years influences FLs in spinal vertebral edges (VEs) of patients suffering from axSpA.

• In a 4-year, phase 3 randomized trial (RAPID-axSpA), patients were randomly assigned to certolizumab pegol (CZP) or placebo (PBO) at baseline; PBO-randomized ones switched to CZP at week 16/24 (denoted PBO-randomized/CZP).

• A total of 136 patients (CZP: 89, PBO-randomized/CZP: 47) had a baseline and ≥1 post-baseline MRI.

• In PBO-randomized/CZP vs CZP-randomized patients, the odds ratios (OR) vs baseline of FLs was found to be higher at Weeks 48 (3.35 vs 1.45), 96 (2.62 vs 1.84) and 204 (2.55 vs 1.71).

• In VEs with baseline inflammation, FLs increased more across 204 weeks (week 204 OR: 4.84) vs those without (OR: 1.15).

• Lower FL prevalence at Weeks 48, 96 and 204 was detected in VEs in which inflammation was resolved by week 12 vs VEs with unresolved inflammation.