Efficacy of thiopurines and adalimumab in preventing Crohn's disease recurrence in high‐risk patients – a POCER study analysis

P De Cruz, M A Kamm, A L Hamilton, K J Ritchie, E O Krejany, A Gorelik, D Liew, L Prideaux, I C Lawrance, J M Andrews, P A Bampton, S Jakobovits, T H Florin, P R Gibson, H Debinski, R B Gearry, F A Macrae, R W Leong, I Kronborg, G Radford-Smith, W Selby, M J Johnston, R Woods, P R Elliott, S J Bell, S J Brown, W R Connell, P V Desmond

Crohn's disease recurs in the majority of patients after intestinal resection. To compare the relative efficacy of thiopurines and anti-TNF therapy in patients at high risk of disease recurrence. As part of a larger study comparing post-operative management strategies, patients at high risk of recurrence (smoker, perforating disease, ≥2nd operation) were treated after resection of all macroscopic disease with 3 months metronidazole together with either azathioprine 2 mg/kg/day or mercaptopurine 1.5 mg/kg/day. Thiopurine-intolerant patients received adalimumab induction then 40 mg fortnightly. Patients underwent colonoscopy at 6 months with endoscopic recurrence assessed blind to treatment. A total of 101 patients [50% male; median (IQR) age 36 (25-46) years] were included. There were no differences in disease history between thiopurine- and adalimumab-treated patients. Fifteen patients withdrew prior to 6 months, five due to symptom recurrence (of whom four were colonoscoped). Endoscopic recurrence (Rutgeerts score i2-i4) occurred in 33 of 73 (45%) thiopurine vs. 6 of 28 (21%) adalimumab-treated patients [intention-to-treat (ITT); P = 0.028] or 24 of 62 (39%) vs. 3 of 24 (13%) respectively [per-protocol analysis (PPA); P = 0.020]. Complete mucosal endoscopic normality (Rutgeerts i0) occurred in 17/73 (23%) vs. 15/28 (54%) (ITT; P = 0.003) and in 27% vs. 63% (PPA; P = 0.002). The most advanced disease (Rutgeerts i3 and i4) occurred in 8% vs. 4% (thiopurine vs. adalimumab). In Crohn's disease patients at high risk of post-operative recurrence adalimumab is superior to thiopurines in preventing early disease recurrence.