Effectiveness of adalimumab in treating patients with ankylosing spondylitis associated with enthesitis and peripheral arthritis

Abstract

Introduction: The purpose of this study was to investigate the effectiveness of adalimumab in enthesitis and peripheral arthritis in patients with ankylosing spondylitis (AS).

Methods: Adults with active AS (Bath ankylosing spondylitis disease activity index [BASDAI] > or = 4) received adalimumab 40 mg every other week with standard antirheumatic therapies in a 12-week, open-label study. Effectiveness in enthesitis was assessed using the Maastricht ankylosing spondylitis enthesitis score (MASES, 0-13) and by examining the plantar fascia in patients with enthesitis (> or = 1 inflamed enthesis) at baseline; effectiveness in peripheral arthritis was evaluated using tender and swollen joint counts (TJC, 0-46; SJC, 0-44) in patients with peripheral arthritis (> or = 1 swollen joint) at baseline. Overall effectiveness measures included Assessment of SpondyloArthritis International Society 20% response (ASAS20).

Results: Of 1,250 patients enrolled, 686 had enthesitis and 281 had peripheral arthritis. In 667 patients with MASES > or = 1 at baseline, the median MASES was reduced from 5 at baseline to 1 at week 12. At week 12, inflammation of the plantar fascia ceased in 122 of 173 patients with inflammation at baseline. The median TJC in 281 patients with SJC > or = 1 at baseline was reduced from 5 at baseline to 1 at week 12; the median SJC improved from 2 to 0. ASAS20 responses were achieved by 70.5% of 457 patients with no enthesitis and no arthritis; 71.0% of 512 patients with only enthesitis; 68.0% of 107 patients with only arthritis; and 66.7% of 174 patients with both.

Conclusions: Treatment with adalimumab improved enthesitis and peripheral arthritis in patients with active AS.

Trial registration: ClinicalTrials.gov NCT00478660.

Figure 1

Distribution of enthesitis or peripheral arthritis or both in patients with ankylosing spondylitis (AS) (n = 1,250). Enthesitis is defined as at least 1 inflamed enthesis in Maastricht Ankylosing Spondylitis Enthesitis Score (MASES) or plantar fascia, and peripheral arthritis is defined as at least 1 swollen joint in a 44-joint count. Data are observed values. *Six hundred sixty-seven patients with enthesitis in MASES and 173 patients with enthesitis of fascia plantaris (19 patients had enthesitis of fascia plantaris without enthesitis in MASES). RHAPSODY, Review of Safety and Effectiveness with Adalimumab in Patients with Active Ankylosing Spondylitis.

Figure 2

Percentages of patients with inflamed entheses at baseline and week 12 by enthesitis site (n = 686). Enthesitis is defined as at least 1 inflamed enthesis in Maastricht Ankylosing Spondylitis Enthesitis Score or plantar fascia and includes patients with ankylosing spondylitis and enthesitis. Data are observed values.

Figure 3

Percentages of patients with ankylosing spondylitis achieving response at week 12. Enthesitis is defined as at least 1 inflamed enthesis in Maastricht Ankylosing Spondylitis Enthesitis Score or plantar fascia, and peripheral arthritis is defined as at least 1 swollen joint in a 44-joint count. Data are observed values. ASAS20/40, Assessment of SpondyloArthritis international Society 20%/40% response; BASDAI 50, 50% improvement in the Bath Ankylosing Spondylitis Disease Activity Index.