Table 2.
Descriptive outcome summary at week 24, overall and stratified by SPEAR status and treatment type
| Outcome | Total | SPEAR patients | Non-SPEAR patients | ABA: SPEAR versus non-SPEAR | Difference in differences [A] − [B] | ||||
|---|---|---|---|---|---|---|---|---|---|
| ABA | Comparator | ABA versus comparator [A] | ABA | Comparator | ABA versus comparator [B] | ||||
| N = 2004 | N = 796 | n = 558 | n = 329 | n = 321 | |||||
| DAS28 (CRP) change from baseline | − 2.36 ± 1.40 | − 2.67 ± 1.34 | − 2.13 ± 1.35 | − 0.54, p < 0.001* | − 2.27 ± 1.41 | − 2.10 ± 1.49 | − 0.17, p = 0.14 | − 0.40, p < 0.001* | − 0.37, p < 0.01* |
| DAS28 (CRP) remission | 587 (29.29) | 301 (37.81) | 138 (24.73) | 13.08, p < 0.001* | 83 (25.23) | 65 (20.25) | 4.98, p = 0.16 | 12.58, p < 0.001* | 8.10, p = 0.14 |
| ACR20 | 1425 (71.11) | 614 (77.14) | 366 (65.59) | 11.55, p < 0.001* | 228 (69.30) | 217 (67.60) | 1.70, p = 0.70 | 7.84, p < 0.01* | 9.85, p < 0.05* |
| ACR50 | 955 (47.65) | 448 (56.28) | 235 (42.11) | 14.17, p < 0.001* | 147 (44.68) | 125 (38.94) | 5.74, p = 0.16 | 11.60, p < 0.001* | 8.43, p = 0.09 |
| ACR70 | 556 (27.74) | 275 (34.55) | 121 (21.68) | 12.87, p < 0.001* | 85 (25.84) | 75 (23.36) | 2.48, p = 0.52 | 8.71, p < 0.01* | 10.39, p < 0.05* |
| SDAI change from baseline | − 27.05 ± 19.88 | − 29.87 ± 21.58 | − 24.61 ± 17.29 | − 5.26, p < 0.001* | − 27.03 ± 19.37 | − 23.83 ± 19.05 | − 3.20, p = 0.07 | − 2.84, p = 0.07 | − 2.06, p = 0.35 |
| SDAI remission | 243 (12.13) | 122 (15.33) | 50 (8.96) | 6.37, p < 0.001* | 37 (11.25) | 34 (10.59) | 0.66, p = 0.89 | 4.08, p = 0.09 | 5.71, p = 0.08 |
| CRP value (mg/dl) change from baseline | − 1.42 ± 2.97 | − 1.64 ± 2.82 | − 1.50 ± 3.28 | − 0.14, p = 0.42 | − 1.06 ± 2.19 | − 1.09 ± 3.38 | 0.03, p = 0.88 | − 0.58, p < 0.01* | − 0.17, p = 0.56 |
| TJC out of 68 joints change from baseline | − 15.86 ± 13.68 | − 16.55 ± 13.22 | − 14.54 ± 13.00 | − 2.01, p < 0.01* | − 16.49 ± 15.27 | − 15.80 ± 14.12 | − 0.69, p = 0.55 | − 0.06, p = 0.95 | − 1.32, p = 0.31 |
| SJC out of 66 joints change from baseline | − 11.54 ± 9.68 | − 12.15 ± 9.61 | − 10.25 ± 9.07 | − 1.90, p < 0.001* | − 12.25 ± 10.87 | − 11.52 ± 9.39 | − 23.77, p = 0.36 | 0.01, p = 0.88 | − 1.16, p = 0.21 |
| HAQ-DI Score change from baseline | − 0.72 ± 0.69 | − 0.85 ± 0.70 | − 0.68 ± 0.66 | − 0.17, p < 0.001* | − 0.65 ± 0.66 | − 0.57 ± 0.66 | − 1.22, p = 0.13 | − 0.20, p < 0.001* | − 0.09, p = 0.15 |
| Patient Global Assessment change from baseline | − 31.69 ± 29.09 | − 36.54 ± 29.70 | − 28.01 ± 28.43 | − 8.53, p < 0.001* | − 30.76 ± 27.04 | − 27.02 ± 29.07 | − 3.74, p = 0.09 | − 5.78, p < 0.01* | − 4.79, p = 0.08 |
| Physician Global Assessment change from baseline | − 42.97 ± 23.53 | − 46.52 ± 23.09 | − 41.21 ± 23.63 | − 5.31, p < 0.001* | − 41.66 ± 23.09 | − 38.53 ± 23.73 | − 3.13, p = 0.09 | − 4.86, p < 0.01* | − 2.18, p = 0.33 |
| Pain visual analog scale change from baseline | − 33.51 ± 29.12 | − 37.99 ± 29.52 | − 29.26 ± 28.43 | − 8.73, p < 0.001* | − 33.25 ± 26.65 | − 30.06 ± 30.23 | − 3.19, p = 0.15 | − 4.74, p < 0.05* | − 5.54, p < 0.05* |
Data are mean ± SD using imputed follow-up data
The p values shown here were not adjusted for multiple comparisons
ABA abatacept, ACPA anti-citrullinated protein antibodies, ACR20/50/70 American College of Rheumatology 20/50/70 criteria, CI confidence interval, CRP C-reactive protein, DAS28 (CRP) Disease Activity Score 28 for RA with C-reactive protein, HAQ-DI Health Assessment Questionnaire Disability Index, RF rheumatoid factor, SD standard deviation, SDAI Simple Disease Activity Index, SJC swollen joint count, SPEAR SeroPositive Early and Active RA, TJC tender joint count
* p < 0.05