Baseline characteristics of patients with axSpA initiating treatment with SEC or an alternative TNFi after previous exposure to one or more TNFis
| Parameter | N=390 | TNFi, n=284 | SEC, n=106 | P value |
| Male sex, n (%) | 390 | 123 (43.3) | 43 (40.6) | 0.65 |
| ASAS classification | 390 | 0.99 | ||
| Positive, n (%) | 177 (62.3) | 67 (63.2) | ||
| Negative, n (%) | 64 (22.5) | 24 (22.6) | ||
| Unknown, n (%) | 43 (15.1) | 15 (14.2) | ||
| Radiographic sacroiliitis, n (%) | 182 | 99 (76.2) | 46 (88.5) | 0.07 |
| Age, years | 390 | 45.0 (12.5) | 46.1 (11.7) | 0.44 |
| Symptom duration, years | 378 | 13.9 (10.5) | 14.7 (11.3) | 0.6 |
| HLA-B27 positive, n (%) | 346 | 147 (58.8) | 53 (55.2) | 0.55 |
| BASDAI | 285 | 4.8 (2.1) | 6.1 (1.9) | <0.001 |
| Physician Global Assessment | 357 | 3.5 (1.9) | 4.5 (1.9) | <0.001 |
| Patient Global Assessment | 280 | 5.3 (2.6) | 6.2 (2.3) | 0.01 |
| ASDAS | 241 | 2.7 (0.9) | 3.4 (1.0) | <0.001 |
| C reactive protein (mg/L); median (IQR) | 340 | 3.0 (1.0–8.0) | 5.0 (1.5–14.2) | 0.003 |
| Elevated C reactive protein, n (%) | 340 | 67 (27.5) | 36 (37.5) | 0.09 |
| BASFI | 270 | 3.0 (2.4) | 4.8 (2.6) | <0.001 |
| BASMI | 206 | 1.8 (1.6) | 2.5 (1.8) | 0.008 |
| EQ-5D | 271 | 61.7 (21.1) | 53.2 (21.1) | 0.001 |
| Current peripheral arthritis, n (%) | 360 | 81 (31.1) | 41 (41.0) | 0.08 |
| Number of swollen joints | 352 | 0.9 (2.7) | 1.1 (2.7) | 0.35 |
| Current enthesitis, n (%) | 354 | 173 (68.1) | 79 (79.0) | 0.05 |
| Modified MASES* | 354 | 2.8 (3.4) | 4.0 (4.1) | 0.009 |
| Dactylitis ever, n (%) | 383 | 42 (15.1) | 19 (18.3) | 0.44 |
| Uveitis ever, n (%) | 377 | 41 (14.9) | 10 (9.8) | 0.24 |
| Inflammatory bowel disease ever, n (%) | 380 | 27 (9.8) | 4 (3.8) | 0.06 |
| Psoriasis ever, n (%) | 374 | 26 (9.5) | 12 (12.0) | 0.56 |
| csDMARDs ever, n (%) | 390 | 124 (43.7) | 46 (43.4) | 1 |
| Current csDMARD, n (%) | 390 | 34 (12.0) | 17 (16.0) | 0.31 |
| Current NSAIDs, n (%) | 337 | 177 (73.1) | 77 (81.0) | 0.16 |
| Smoker ever, n (%) | 354 | 157 (61.6) | 68 (68.7) | 0.22 |
| Exercise sessions/week | 180 | 2.7 (2.6) | 3.4 (3.1) | 0.3 |
| Body mass index (kg/m2) | 214 | 26.5 (5.3) | 27.3 (5.7) | 0.38 |
| Number of previous bDMARDs, n (%) | 390 | <0.001 | ||
| 1 (second-line treatment) | 170 (59.9) | 25 (23.6) | ||
| 2 (third-line treatment) | 60 (21.1) | 36 (34.0) | ||
| ≥3 (>third-line treatment) | 54 (19.0) | 45 (42.4) | ||
| Reason of discontinuation of previous TNFi | 350 | 0.17 | ||
| Ineffectiveness, n (%) | 171 (69.0) | 68 (66.7) | ||
| Adverse events, n (%) | 38 (15.3) | 24 (23.5) | ||
| Other, n (%) | 39 (15.7) | 10 (9.8) |
Except where indicated otherwise values are the mean (SD).
*Modification refers to the inclusion of the plantar fascia in the count.
ASAS, Assessment in SpondyloArthritis international Society; ASDAS, Ankylosing Spondylitis Disease Activity Score; axSpA, axial spondyloarthritis; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; BASMI, Bath Ankylosing Spondylitis Metrology Index; bDMARD, biological disease-modifying antirheumatic drug; csDMARD, conventional synthetic disease-modifying antirheumatic drug; EQ-5D, EuroQol-5 domains; HLA-B27, human leucocyte antigen B27; MASES, Maastricht Ankylosing Spondylitis Enthesitis Score; NSAIDs, non-steroidal anti-inflammatory drugs; SEC, secukinumab; TNFi, tumour necrosis factor inhibitor.