Predictive factors for structural remission using abatacept: Results from the ABROAD study

Objective: To investigate the effect of abatacept (ABA) on preventing joint destruction in biological disease-modifying anti-rheumatic drug (bDMARD)-naive rheumatoid arthritis (RA) patients in real-world clinical practice. Patients and methods: RA patients were collected from the ABROAD (ABatacept Research Outcomes as a First-line Biological Agent in the Real WorlD) study cohort. They had moderate or high disease activity and were treated with ABA as a first-line bDMARD. Radiographic change between baseline and 1 year after ABA treatment was assessed with the van der Heijde's modified Total Sharp Score (mTSS). Predictive factors for structural remission (St-REM), defined as Delta mTSS <= 0.5/year, were determined. Results: Among 118 patients, 81 (67.5%) achieved St-REM. Disease duration <3 years (odds ratio (OR) = 3.152, p = .007) and slower radiographic progression (shown as 'baseline mTSS/year <3', OR = 3.727, p = .004) were independently significant baseline predictive factors for St-REM irrespective of age and sex. St-REM prevalence increased significantly if clinical remission based on the Simplified Disease Activity Index was achieved at least once until 24 weeks after ABA treatment. Conclusion: Shorter disease duration, smaller radiographic progression at baseline, and rapid clinical response were predictive factors for sustained St-REM after ABA therapy in bDMARD-naive RA patients.