Therapeutic failure during 1 year (primary end point) due to clinical recurrence (defined as Crohn's disease activity index score ≥200 and an increase of ≥60 points from baseline) or study discontinuation due to lack of efficacy or adverse drug reaction
| Azathioprine | Mesalazine | Difference in proportions* (95% CI) | p Value† | |
| Intention-to-treat population | n=41 | n=37 | ||
| Therapeutic failure | 9 (22.0%) | 4 (10.8%) | 11.1% (−5.0% to 27.3%) | 0.19 |
| Clinical recurrence or discontinuation due to lack of efficacy | 0 | 4 (10.8%) | −10.8% (−20.8% to −0.8%) | 0.031 |
| Discontinuation due to adverse drug reaction‡ | 9 (22.0%) | 0 | 22.0% (9.3% to 34.6%) | 0.002 |
| Per-protocol population | n=33 | n=31 | ||
| Therapeutic failure | 9 (27.3%) | 3 (9.7%) | 17.6% (−0.8% to 36.0%) | 0.072 |