Table 2.
Mean (SEM) change from baseline for clinical efficacy and patient-reported outcomes
| Double-blind phase | Open-label phase | p Values† | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Week 12 | Week 12 p Value* |
Week 16 | Week 24 | Week 32 | Week 40 | Week 48 | Week 12– week 48 | Week 24– week 48 | ||
| N=Pts in study | ETN/ETN | N=101 | N=99 | N=98 | N=94 | N=93 | N=91 | |||
| PBO/ETN | N=106 | N=104 | N=103 | N=100 | N=99 | N=99 | ||||
| ASDAS-CRP | ETN/ETN | −1.1 (0.1) | <0.001 | −1.4 (0.1) | −1.5 (0.1) | −1.4 (0.1) | −1.6 (0.1) | −1.6 (0.1) | <0.001 | <0.05 |
| PBO/ETN | −0.5 (0.1) | −1.4 (0.1) | −1.6 (0.1) | −1.5 (0.1) | −1.6 (0.1) | −1.6 (0.1) | ||||
| BASDAI | ETN/ETN | −2.0 (0.3) | <0.05 | −2.7 (0.2) | −2.9 (0.2) | −2.7 (0.2) | −3.2 (0.2) | −3.2 (0.2) | <0.001 | <0.05 |
| PBO/ETN | −1.3 (0.3) | −3.0 (0.2) | −3.3 (0.2) | −3.2 (0.2) | −3.4 (0.2) | −3.5 (0.2) | ||||
| BASFI | ETN/ETN | −1.4 (0.2) | <0.05 | −1.8 (0.2) | −1.9 (0.2) | −1.8 (0.2) | −2.2 (0.2) | −2.2 (0.2) | <0.001 | <0.01 |
| PBO/ETN | −0.8 (0.2) | −1.8 (0.2) | −1.9 (0.2) | −2.0 (0.2) | −2.1 (0.2) | −2.1 (0.2) | ||||
| BASMI | ETN/ETN | −0.3 (0.2) | NS | −0.4 (0.1) | −0.5 (0.1) | −0.6 (0.1) | −0.5 (0.1) | −0.5 (0.1) | NS | NS |
| PBO/ETN | −0.3 (0.1) | −0.4 (0.1) | −0.3 (0.1) | −0.5 (0.1) | −0.5 (0.1) | −0.4 (0.1) | ||||
| Total back pain | ETN/ETN | −2.0 (0.3) | <0.01 | −2.7 (0.3) | −2.8 (0.3) | −2.6 (0.3) | −3.3 (0.3) | −3.1 (0.3) | <0.01 | <0.05 |
| PBO/ETN | −1.1 (0.3) | −2.6 (0.3) | −2.9 (0.2) | −2.9 (0.3) | −3.2 (0.2) | −3.2 (0.3) | ||||
| SF-36 PCS | ETN/ETN | 6.2 (1.0) | <0.05 | NA | 6.7 (0.9) | NA | NA | 8.0 (1.0) | <0.05 | NS |
| PBO/ETN | 3.8 (0.9) | NA | 7.3 (0.8) | NA | NA | 8.5 (0.9) | ||||
| SF-36 MCS | ETN/ETN | 2.4 (1.3) | NS | NA | 3.5 (1.3) | NA | NA | 3.5 (1.2) | NS | NS |
| PBO/ETN | 1.6 (1.2) | NA | 4.4 (1.0) | NA | NA | 3.5 (1.1) | ||||
| EQ-5D utility score | ETN/ETN | 0.14 (0.04) | NS | 0.19 (0.04) | 0.21 (0.03) | NA | 0.24 (0.04) | 0.23 (0.03) | NS | NS |
| PBO/ETN | 0.08 (0.03) | 0.17 (0.03) | 0.20 (0.03) | NA | 0.18 (0.03) | 0.22 (0.03) | ||||
| N=Pts with work data | ETN/ETN | N=48 | N=49 | N=45 | N=46 | N=45 | N=45 | |||
| PBO/ETN | N=50 | N=46 | N=43 | N=43 | N=47 | N=45 | ||||
| WPAI overall | ETN/ETN | −20.8 (4.9) | NS | −16.3 (3.8) | −14.9 (4.5) | −17.6 (3.8) | −23.7 (4.2) | −23.0 (3.6) | <0.05 | NS |
| PBO/ETN | −12.1 (4.9) | −16.4 (2.9) | −18.6 (3.7) | −16.5 (3.3) | −20.5 (3.0) | −17.5 (3.9) | ||||
*Analysis of covariance model used for between-group p values.
†Paired t test used for within-group response difference for ETN/ETN.
Analyses performed on mITT, LOCF population for ASDAS-CRP, BASDAI, BASFI, BASMI, total back pain; mITT, observed case population for SF-36 PCS, SF-36 MCS, EQ-5D utility score, WPAI overall.
ASDAS-CRP, Ankylosing Spondylitis Disease Activity Score based on C-reactive protein; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BASFI, Bath Ankylosing Spondylitis Functional Index; BASMI, Bath Ankylosing Spondylitis Metrology Index; EQ-5D, EuroQol 5 Dimensions; ETN, etanercept; LOCF, last observation carried forward; MCS, mental component summary; mITT, modified intention-to-treat; NA, not available, NS, non-significant; PCS, physical component summary; PBO, placebo; Pts, patients; SEM, SE of the mean; SF-36, 36-item Short Form Health Survey; WPAI, Work Productivity and Activity Impairment questionnaire.