Table 5.
Trial design and patient characteristics associated with treatment effect sizes in trials in ulcerative colitis
| Covariate | Univariable regression | Multivariable regression | ||
| Coefficient | P value | Coefficient | P value | |
| Mean age in the active arm (per 1-yr increase) | −0.030 | 0.107 | ||
| Mean age in the placebo arm (per 1-yr increase) | −0.038 | 0.096 | ||
| Mean total Mayo score in the active arm (per 1-point increase) | −0.254 | 0.141 | ||
| Mean total Mayo score in the placebo arm (per 1-point increase) | −0.262 | 0.158 | ||
| Percentage of extensive colitis in the active arm (per 1% increase) | −0.014 | 0.107 | ||
| Percentage of extensive colitis in the placebo arm (per 1% increase) | −0.017 | 0.017 | −0.005 | 0.753 |
| Mean disease duration in the active arm (per 1-yr increase) | −0.040 | 0.104 | ||
| Mean disease duration in the placebo arm (per 1-yr increase) | −0.0008 | 0.99 | ||
| Percentage of concomitant immunosuppressants in the active arm (per 1% increase) | −0.009 | 0.079 | ||
| Percentage of concomitant immunosuppressants in the placebo arm (per 1% increase) | −0.010 | 0.023 | −0.003 | 0.674 |
| Percentage of concomitant steroids in the active arm (per 1% increase) | −0.002 | 0.517 | ||
| Percentage of concomitant steroids in the placebo arm (per 1% increase) | −0.0004 | 0.865 | ||
| Percentage of previous biologics in the active arm (per 1% increase) | 0.003 | 0.516 | ||
| Percentage of previous biologics in the placebo arm (per 1% increase) | 0.003 | 0.485 | ||
| Mean/median baseline CRP in the active arm (per 1 mg/L increase) | −0.054 | 0.019 | 0.003 | 0.807 |
| Mean/median baseline CRP in the placebo arm (per 1 mg/L increase) | −0.040 | 0.135 | ||
| No. of follow-up visits (per 1 visit increase) | −0.122 | 0.647 | ||
| Duration of follow-up in wk (per 1-wk increase) | 0.029 | 0.177 | ||
| Setting (Multicenter single country vs multicenter multi-country) | 0.123 | 0.521 | ||
| First-author country (North America as reference) | Europe | 0.213 | 0.253 | |
| Other | −0.128 | |||
| Drug class (vs anti-TNF as reference) | JAK inhibitor | 0.590 | NS | |
| Anti-IL-12/23 | 0.145 | |||
| Anti-integrin | −0.036 | |||
| Other | 0.486 | |||
| Route of administration (vs oral as reference) | Intravenous | −0.319 | 0.118 | |
| Subcutaneous | −0.379 | |||
| Minimum total Mayo score at entry (≥6 vs <6) | 0.189 | 0.148 | ||
| Bleeding subscore not required at entry (vs required) | −0.370 | 0.009 | −0.493 | 0.037 |
| Improvement in endoscopic subscore not required for endpoint (vs required) | −0.074 | 0.526 | ||
| Improvement in bleeding subscore not required for endpoint (vs required) | −0.296 | 0.012 | −0.156 | 0.674 |
| Randomization ratio active drug vs placebo (>1 vs ≤1) | −0.033 | 0.845 | ||
Entries in bold denote P < 0.05 in the regression analysis.
CRP, C-reactive protein; IL, interleukin; JAK, Janus kinase; TNF, tumor necrosis factor.