Background/Purpose: Intensive treatment of early rheumatoid arthritis (RA) has been shown to reduce functional disability over time and to positively impact employment outcomes. Adalimumab (ADA) is approved for the treatment of RA and has demonstrated improvements in clinical, patient-reported, and work productivity outcomes.^1,2 We aimed to evaluate the effects of combination therapy with ADA plus methotrexeate (MTX) compared with MTX monotherapy on work instability outcome, a significant predictor of employment loss, among patients at elevated risk for job loss.

Methods: A secondary analysis was conducted using data from the 26 week, randomized, double-blind period of OPTIMA, a study designed to compare the safety and efficacy of ADA plus MTX to placebo plus MTX in subjects with early (<1 year duration), active RA.  Work instability was assessed using the Rheumatoid Arthritis-Work Instability Scale (RA-WIS) (range 0–23), where scores of ≥17, ≥10 to <17, and <10 represent high-, medium-, or low-risk for job loss. To meet study objectives, only employed patients with baseline RA-WIS score ≥10 (moderate to high risk) were included in this analysis. Improvements of 5 points in RA-WIS has been determined to be clinically meaningful. Chi-square tests were used to assess treatment group differences in the percentage of patients who: a) demonstrated improvement by at least 1 risk category; and b) achieved improvements of ≥5, ≥7 or ≥9 points, at Weeks 4, 12 and 26 from baseline. Missing values were imputed using NRI method. As sensitivity analysis, responders were defined as patients with both improvement by at least 1 category and a ≥5 point change.

Results: A total of 320 patients (146 ADA plus MTX; 174 PBO plus MTX) were included in the analysis sample (mean age: 46; females: 69%). The mean baseline RA-WIS score was 16.7(±3.8). Significant differences favoring ADA were observed among patients who improved by at least 1 risk category at Weeks 4, 12, and 26 (50% vs 33%; P=.0025, 62% vs 44%; P=.0019, and 58% vs 47%; P=.048, respectively). A significantly greater percentage of ADA treated patients also improved by 5 points (42% vs 23%; P=.0003, 58% vs 43%; P=.010, and 56% vs 43%, P<.027 at Weeks 4, 12, and 26, respectively), 7 points (29% vs 16%; P=.004, 45% vs 33%; P=.031, and 47% vs 36%; P=.035 at Weeks 4, 12, and 26, respectively), or 9 points (23% vs 9%; P=.0008, 34% vs 23%; P=.036, and 42% vs 26%, P=.004 at Weeks 4, 12, and 26, respectively) compared to patients receiving MTX monotherapy. Sensitivity analysis also showed significant differences favoring patients treated with ADA at Weeks 4, 12 and 26 (38% vs 21%; P<.001, 53% vs 38%; P<.001, and 53% vs 41%; P=.031, respectively).

Conclusion: Among early RA patients with elevated risk of employment loss, combination therapy with ADA plus MTX was associated with clinically meaningful greater improvements in RA-WIS compared with MTX monotherapy.

References:

¹Bejarano V, et al. Arthritis Rheum. 2008;59:1467–74.

²van Vollenhoven R, et al. Arthritis Care Res. 2010;62:226–34.