Table 2

Disease activity 3 months prior to vs 3 months after the switch from ETA to SB4 stratified by indication

Disease activityChanges over time
3 months preswitchSwitch3 months postswitch∆Preswitch∆Postswitch
RA, n=933
 Patients with available data, n (%)*639 (68)745 (80)568 (61)485 (52)436 (47)
 DAS281.9 (1.3 to 2.8)2.1 (1.6 to 3.0)2.1 (1.7 to 3.1)0.0 (0.0 to 0.0)0.0 (−0.4 to 0.5)
 HAQ (0–3)0.8 (0.3 to 1.3)0.8 (0.3 to 1.3)0.8 (0.3 to 1.3)0 (−1 to 1)0 (−1 to 1)
 CRP, mg/L3 (1 to 7)3 (1 to 6)3 (1 to 6)0 (−2 to 1)0 (−1 to 1)
 PGS, mm30 (14 to 57)29 (13 to 55)32 (12 to 62)0 (−11 to 8)1 (−8 to 11)
PsA, n=351
 Patients with available data, n (%)*223 (64)253 (72)197 (56)158 (45)152 (43)
 DAS281.8 (1.1 to 2.4)2.0 (1.6 to 2.8)2.1 (1.5 to 2.8)0.0 (0.0 to 0.0)0.1 (−0.4 to 0.5)
 HAQ (0–3)0.5 (0.1 to 1.0)0.5 (0.0 to 1.0)0.5 (0.1 to 1.0)0.0 (−0.1 to 0.1)0.0 (−0.1 to 0.1)
 CRP, mg/L2 (1 to 4)2 (1 to 4)2 (1 to 4)0 (−2 to 1)0 (−1 to 1)
 PGS, mm33 (13 to 58)30 (12 to 54)31 (12 to 58)0 (−9 to 6)0 (−7 to 10)
AxSpA, n=337
 Patients with available data, n (%)*187 (55)217 (64)243 (72)117 (35)168 (50)
 BASDAI, mm33 (15 to 52)27 (12 to 47)31 (18 to 52)0 (−8 to 6)1 (−3 to 10)
 CRP, mg/L3 (1 to 6)3 (1 to 5)3 (1 to 5)0 (−2 to 1)0 (−1 to 1)
 PGS, mm32 (15 to 59)30 (12 to 53)34 (17 to 60)−1 (−13 to 6)3 (−5 to 14)
 ASDAS1.9 (1.3 to 2.8)1.9 (1.2 to 2.6)1.9 (1.3 to 2.7)−0.1 (−0.4 to 0.3)0.1 (−0.2 to 0.6)
3 months’ flare rates preswitch vs postswitch†
 RA (ΔDAS28 ≥0.6), %2224
 PsA (ΔDAS28 ≥0.6), %2123
 RA (ΔDAS28 ≥1.2), %813
 PsA (ΔDAS28 ≥1.2), %811
 AxSpA (ΔASDAS >1.1), %45
  • Numbers are medians (interquartile ranges) unless otherwise stated (%).

  • Missing data at the 3 months’ visit were imputed with the 6 months’ visit according to the following time windows:

  • Time windows preswitch: 3 months’ window: 0 to 25 weeks, 6 months’ window: 25 to 32 weeks before start of SB4.

  • Time window switch: 12 weeks before until 1 week after start of SB4.

  • Time window postswitch: 3 months’ window: 9 to 17 weeks, 6 months’ window: 17 to 32 weeks after start of SB4. Overlapping time windows at baseline were allowed to reduce missing data. Any visit was only used once, and the registration closest to the given time point was selected. If a patient had no registrations, data were registered as missing for that visit.

  • *Number of patients with available data varied slightly across measures of disease activity. Exact numbers are shown for DAS28 and ASDAS. Individual patients might not have complete data for all variables at a certain time point. Comparisons of before vs after the switch were done in the patients who had complete data for that variable.

  • †There was no overlap between the patients who had a flare preswitch vs postswitch.

  • ‡Comparison of ∆preswitch vs ∆postswitch byWilcoxon matched-pair signed rank test.

  • ASDAS, the Ankylosing Spondylitis Disease Activity Score; AxSpA, axial spondyloarthritis; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; CRP, C reactive protein; DAS28, 28-joint Disease Activity Score (four variables, CRP-based); ETA, originator etanercept; HAQ, Health Assessment Questionnaire; PGS, patient’s global score; PsA, psoriatic arthritis; RA, rheumatoid arthritis; SB4, biosimilar etanercept.