Baseline characteristics of the total axSpA patients, AS and nr-axSpA subpopulations
| Total axSpA | Total axSpA (n=325) | AS (n=178) | nr-axSpA (n=147) | |||
|---|---|---|---|---|---|---|
| Placebo (n=107) | CZP 200 mg Q2W (n=111) | CZP 400 mg Q4W (n=107) | ||||
| Demographic characteristics | ||||||
| Age, mean yrs (SD) | 39.9 (12.4) | 39.1 (11.9) | 39.8 (11.3) | 39.6 (11.9) | 41.5 (11.6) | 37.4 (11.8) |
| Male, % | 60.7 | 60.4 | 63.6 | 61.5 | 72.5 | 48.3 |
| AxSpA characteristics | ||||||
| Symptom duration, median, yrs (min, max) | 7.7 (0.3, 50.9) | 6.9 (0.3, 34.2) | 7.9 (0.3, 44.8) | 7.7 (0.3, 50.9) | 9.1 (0.3,50.9) | 5.5 (0.3,41.5) |
| Symptom duration <5 years, n (%) | 42 (39.3) | 50 (45.0) | 34 (31.8) | 126 (38.8) | 57 (32.0) | 69 (46.9) |
| Definitive sacroiliitis on X-ray | 57 (53.3) | 65 (58.6) | 56 (52.3) | 178 (54.8) | 178 (100.0) | 0 (0.0) |
| Positive for HLA-B27, n (%) | 87 (81.3) | 87 (78.4) | 81 (75.7) | 255 (78.5) | 145 (81.5) | 110 (74.8) |
| CRP mg/L | ||||||
| Median, (min, max) | 15.0 (0.1, 156.2) | 12.7 (0.1, 174.8) | 12.3 (0.1, 159.9) | 13.9 (0.1, 174.8) | 14.3 (0.1,174.8) | 11.9 (0.1,156.2) |
| >ULN, n (%) | 77 (72.0) | 75 (67.6) | 71 (66.4) | 223 (68.6) | 130 (73.0) | 93 (63.3) |
| ≥15 mg/L, n (%) | 53 (49.5) | 42 (37.8) | 38 (35.5) | 133 (40.9) | 80 (44.9) | 53 (36.1) |
| BASDAI,* Mean (SD) | 6.4 (1.7) | 6.5 (1.6) | 6.4 (1.5) | 6.4 (1.6) | 6.4 (1.6) | 6.5 (1.5) |
| BASFI, * Mean (SD) | 5.5 (2.1) | 5.3 (2.3) | 5.4 (2.3) | 5.4 (2.3) | 5.7 (2.2) | 4.9 (2.3) |
| BASMI linear,* Mean (SD) | 4.0 (1.8) | 3.7 (1.6) | 3.8 (1.7) | 3.8 (1.7) | 4.4 (1.7) | 3.2 (1.5) |
| ASDAS,* Mean (SD) | 4.0 (0.9) | 3.9 (0.9) | 3.8 (0.8) | 3.9 (0.9) | 4.0 (0.9) | 3.8 (0.9) |
| Arthritis,† n (%) | 61 (57.0) | 62 (55.9) | 53 (49.5) | 176 (54.2) | 96 (53.9) | 80 (54.4) |
| Prior and concomitant medication | ||||||
| Concomitant NSAIDs, n (%) | 92 (86.0) | 97 (87.4) | 95 (88.8) | 285 (87.7) | 162 (91.0) | 123 (83.7) |
| Concomitant DMARDs, n (%) | 38 (35.5) | 31 (27.9) | 31 (29.0) | 100 (30.7) | 63 (35.4) | 37 (25.2) |
| Prior anti-TNFα exposure, n (%) | 26 (24.3) | 15 (13.5) | 11 (10.3) | 52 (16.0) | 36 (20.2) | 16 (10.9) |
Unless stated otherwise data refers to the randomised set (RS). AS, ankylosing spondylitis; ASDAS, Ankylosing Spondylitis Disease Activity Score; axSpA, axial spondyloarthritis; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; BASMI linear, Bath Ankylosing Spondylitis Metrology Index linear; CRP, C-reactive protein; CZP, certolizumab pegol; DMARDs, Disease modifying antirheumatic drugs; HLA-B27, human leukocyte antigen B27; NSAIDs, Non-steroidal anti-inflammatory drugs; nr-axSpA, non-radiographic axial spondyloarthritis; Q2W, every 2 weeks; Q4W, every 4 weeks; TNFα, tumor necrosis factor α; ULN, upper limit of normal.
*In full analysis set (FAS).
†Current and/or historical; CRP ULN=7.9 mg/L.