Background/Purpose: In the ABILITY-1 trial, adalimumab (ADA) treatment for 12 weeks was associated with improved clinical and health-related quality of life (HRQOL) outcomes among patients with nonradiographic axial spondyloarthritis (nr-axSpA).¹ We aimed to evaluate physical function, HRQOL and work productivity over 3 years of ADA treatment in ABILITY-1.

Methods: ABILITY-1 was a 3-year, phase 3, multicenter, randomized, controlled trial of ADA vs placebo in patients with nr-axSpA (classified using the Assessment of SpondyloArthritis international Society axial SpA criteria). After a 12-week double-blind phase, all patients switched to open-label ADA for an additional 144 weeks (156 total). This post hoc analysis evaluated patient-reported outcomes through year 3 among 185 patients overall and among subgroups of 142/43 patients with/without elevated C-reactive protein (CRP) and/or MRI evidence of inflammation at baseline. Physical function was assessed using the disability index of the Health Assessment Questionnaire for Spondyloarthropathies (HAQ-S) and HRQOL using the Short Form 36 Health Survey (SF-36) Physical Component Summary (PCS) score. Productivity was assessed using the Work Productivity and Activity Impairment Questionnaire (WPAI). Changes in HAQ-S, SF-36 PCS, and WPAI from baseline to years 1, 2, and 3 were reported for the ITT populations (LOCF).

Results: No significant differences were observed between patient cohorts in baseline HAQ-S, SF-36 PCS, or WPAI domain scores. Mean change from baseline in HAQ-S indicated sustained improvement over time among patients in the overall population at years 1, 2, or 3 (-0.39, -0.40, and -0.39, respectively); a majority of patients (56%, 55%, and 54%, respectively) achieved the minimum clinically important difference (MCID) of -0.26² (Table). Trends were similar for SF-36 PCS score; approximately 68% of patients achieved the MCID of 3.0³ at each time point; mean scores were 41.8, 41.9, and 41.9 at years 1, 2, and 3, respectively, compared to the US general population norm of 50⁴. Mean changes from baseline in overall work impairment and activity impairment were stable over time, and >60% of patients achieved the MCID of -7.0%⁵ at each time point. Improvements were sustained among patients with and without elevated CRP and/or positive MRI, and in observed case analysis.

Conclusion: Treatment of nr-axSpA with ADA was associated with significant and sustained improvements in physical function, HRQOL, and work productivity over 3 years of the ABILITY-1 trial among patients with and without elevated CRP and/or positive MRI as well as the overall nr-axSpA population.

References:

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