3.2 Clinical, endoscopic and histological endpoints
SECONDARY, REMISSION, RECTAL BLEEDING
In the mercaptopurine group, 16 out of 29 [55.2%] patients continued the study drug up to week 52, compared to 13 out of 30 [43.3%] in the placebo group. At week 52, 14 out of 29 [48.3%] mercaptopurine users achieved the primary endpoint of combined clinical remission and endoscopic improvement compared to three out of 30 [10%] patients in the placebo group (Δ = 38.3%, 95% confidence interval [CI] 17.1–59.4, The proportion of patients achieving corticosteroid-free efficacy endpoints at week 52 in an intention-to-treat analysis. [A] The proportion of patients achieving the primary endpoint: corticosteroid-free combined clinical remission and endoscopic improvement [i.e. total score ≤2, and no item >1, using the 12-point Mayo score consisting of stool frequency, rectal bleeding, endoscopic Mayo score and the physician’s global assessment] and the secondary corticosteroid-free endpoints: endoscopic improvement [i.e. endoscopic Mayo score = 0 or 1], clinical remission [i.e. rectal bleeding score = 0 and stool frequency score = 0 or 1 using the 6-point Mayo score with rectal bleeding and stool frequency score] and histological remission [i.e. absence of neutrophils in the mucosa; Geboes score <2 B.1, Robarts histopathology index ≤3 and/or Nancy score ≤1], at week 52 with delta difference, 95% CI of difference and At week 12, three patients in the mercaptopurine arm and two patients in the thiopurine group did not succeed in tapering down corticosteroids. None of the patients using corticosteroids beyond week 12 reached the primary endpoint at week 52.