Table 1.
Imputation in patients with <2 analysable mTSS* | mTSS change from BL at week 24 | ||||
---|---|---|---|---|---|
Placebo (n=136) | CZP 200 mg Q2W (n=138) | CZP 400 mg Q4W (n=135) | CZP 200 mg Q2W+CZP 400 mg Q4W (n=273) | ||
Prespecified† | Minimum observed score (0) if missing BL Maximum observed score (356.5) if missing week 24 |
28.9 (7.73) | 11.5 (7.59) p=0.071‡ |
25.1 (7.92) p=0.688‡ |
18.3 (6.07) p=0.203 |
Post hoc 1§ | No imputation | 0.29 (0.08) | 0.01 (0.08) p=0.004‡ |
0.12 (0.08) p=0.083‡ |
0.06 (0.06) p=0.008 |
Post hoc 2¶ | Median mTSS change from BL of all patients observed | 0.28 (0.07) | 0.01 (0.07) p=0.004‡ |
0.11 (0.08) p=0.072‡ |
0.06 (0.06) p=0.007 |
Post hoc 3¶ | Mean mTSS change from BL of all patients observed | 0.28 (0.07) | 0.01 (0.07) p=0.004‡ |
0.11 (0.08) p=0.072‡ |
0.06 (0.06) p=0.007 |
Post hoc 4¶ | Maximum mTSS change from BL of all patients observed | 0.66 (0.13) | 0.18 (0.13) p=0.003‡ |
0.52 (0.13) p=0.380‡ |
0.35 (0.10) p=0.028 |
Post hoc 5¶ | Maximum mTSS change from BL by treatment group | 0.39 (0.11) | 0.14 (0.11) p=0.077‡ |
0.49 (0.12) p=0.483‡ |
0.31 (0.09) p=0.538 |
Values are least squares mean (SE). For placebo patients who escaped early to CZP, the week 24 values were linearly extrapolated. p Values of CZP versus placebo are based on analysis of covariance.
*For patients with two radiographs but missing week 24 or baseline film, linear extrapolation was performed in all approaches.
†21 patients had fewer than two analysable mTSS; the number of patients was not equally distributed between the treatment groups.
‡The study was not powered to detect statistical significance between individual CZP dosage groups and placebo, therefore, these p values should be considered nominal.
§26 patients had fewer than two analysable mTSS more than 8 weeks apart (required for post hoc analysis).
¶28 patients had fewer than two analysable mTSS more than 8 weeks apart, including two placebo patients who escaped to CZP before their second mTSS.
BL, baseline; CZP, certolizumab pegol; mTSS, modified Total Sharp Score; Q2W, every 2 weeks; Q4W, every 4 weeks.