Table 6

Responsiveness of biomarkers during the first 22 weeks of anti-TNF therapy stratified according to treatment response

Improvement in ASDASBASDAI response
No/clinically important (<2.00) N=24Major (≥2.0) N=23ΔSRMNon-responder (<50% or 20 mm) N=18Responder (≥50% or 20 mm) N=35
Mean change (SD)SRMMean change (SD)SRMMean change (SD)SRMMean change (SD)SRMΔSRM
Osteocalcin (µg/l)−3.1 (6.70)−0.476.36 (7.52)0.851.31−1.0 (7.8)−0.132.7 (8.4)0.310.45
IL-6 (ng/l)−11.3 (32.4)−0.35−13.1 (11.37)−1.15−0.80−9.5 (15.2)−0.63−14.3 (27.1)−0.530.10
VEGF (ng/l)−36.4 (140.1)−0.26−56.6 (61.61)−0.92−0.66−45.1 (161.3)−0.28−48.1 (59.4)−0.81−0.53
CRP (mg/l)−3.7 (8.08)−0.46−38.9 (36.64)−1.06−0.60−7.3 (14.9)−0.49−28.4 (34.0)−0.84−0.34
Aggrecan (µg/l)18.2 (64.2)0.2878.2 (95.34)0.820.5414.7 (93.2)0.1653.6 (95.7)0.560.40
CTX-II (ng/mmol)−60 (198.9)−0.30−176.9 (274.50)−0.64−0.34−15.0 (251.1)−0.06−206.1 (317.2)−0.65−0.59
MMP-3 (µg/l)−14.1 (55.8)−0.25−81.3 (141.68)−0.57−0.32−24.9 (74.4)−0.33−54.2 (120.1)−0.45−0.12
CTX-I (µg/l)−0.04 (0.12)−0.290.01 (0.20)0.020.31−0.01 (0.1)−0.09−0.01 (0.18)−0.090.00
YKL-40 (µg/l)−11.1 (54.8)−0.20−8.7 (18.2)−0.49−0.28−14.3 (65.8)−0.22−8.7 (17.5)−0.50−0.28
COMP (µg/l)0.08 (0.27)0.310.11 (0.30)0.370.060.04 (0.3)0.160.12 (0.3)0.420.26
  • The results are ranked after the difference in standardised response mean (ΔSRM) for improvement in ASDAS. The sign gives the direction of the change, that is, minus when the biomarker decreases and plus when the biomarker increases, and for the difference in responsiveness.

  • The analyses included 60 patients at baseline and 53 patients at week 22. ASDAS could not be determined in four patients at baseline and in five patients at week 22, and the analyses included 56 patients at baseline and 47 patients at week 22. Seven patients were excluded before week 22.

  • ASDAS, ankylosing spondylitis disease activity score; BASDAI, Bath ankylosing spondylitis disease activity index; COMP, cartilage oligomeric matrix protein; CRP, C-reactive protein; CTX-I, C-terminal cross-linking telopeptide of type I collagen; CTX-II, C-terminal crosslinking telopeptide of type II collagen; IL-6, interleukin 6; MMP-3, matrix metalloproteinase 3; SD, standard deviation; SRM, standardised response mean; VEGF, vascular endothelial growth factor.