Objective The aim of the study was to compare azathioprine versus mesalazine tablets for the prevention of clinical recurrence in patients with postoperative Crohn's disease (CD) with moderate or severe endoscopic recurrence. Methods This was a 1 year, double-blind, doubledummy, randomised study which took place in 21 gastroenterology centres in Austria, the Czech Republic, Germany and Israel. The study participants were 78 adults with CD who had undergone resection with ileocolonic anastomosis in the preceding 6e24 months without subsequent clinical recurrence and with a Crohn's disease activity index (CDAI) score <200, but with moderate or severe endoscopic recurrence. The study drugs were azathioprine 2.0e2.5 mg/kg/day or mesalazine 4 g/day over 1 year. The primary end point was therapeutic failure during 1 year, defined as a CDAI score $200 and an increase of $60 points from baseline, or study drug discontinuation due to lack of efficacy or intolerable adverse drug reaction. Results Treatment failure occurred in 22.0% (9/41) of azathioprine-treated patients and 10.8% (4/37) of mesalazine-treated patients, a difference of 11.1% (95% CI À5.0% to 27.3%, p¼0.19). Clinical recurrence was significantly less frequent with azathioprine versus mesalazine (0/41 (0%) vs 4/37 (10.8%), p¼0.031), whereas study drug discontinuation due to adverse drug reactions only occurred in azathioprine-treated patients (9/41 (22.0%) vs 0%, p¼0.002). The proportion of patients showing $1 point reduction in Rutgeerts score between baseline and month 12 was 63.3% (19/30) and 34.4% (11/32) in the azathioprine and mesalazine groups, respectively (p¼0.023). Conclusions In this population of patients with postoperative CD at high risk of clinical recurrence, superiority for azathioprine versus mesalazine could not be demonstrated for therapeutic failure. Clinical trial registration number NCT00946946.

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This is, to our knowledge, the first study examining the efficacy of CT-P13 induction therapy on mucosal healing in UC. The results indicate that mucosal healing is achieved in two-thirds of UC patients by the end of the induction treatment with CT-P13.

Background and Aims Patients’ perspectives after switching from originator to biosimilar adalimumab have yet to be assessed. We evaluated the efficacy of switching from the originator adalimumab to a biosimilar compound [SB5] in patients with inflammatory bowel disease [IBD]. Methods Data on IBD patients who were switched from the originator to biosimilar adalimumab [SB5] at IBD Center ISCARE were analysed. Disease activity was assessed using standard clinical indices (Harvey-Bradshaw index [HBI] for Crohn’s disease [CD] and partial Mayo score for ulcerative colitis [UC]), and laboratory parameters (C-reactive protein [CRP] and faecal calprotectin [FC]). Trough levels and anti-drug antibodies were measured. Patients were evaluated 10 weeks [W10] after the switch, and results were compared with the control group of patients on originator compound. Results A total of 93 patients switched to biosimilar adalimumab were included [CD 86%] and were matched to 93 controls for age, gender, diagnosis, and disease activity. There was no difference in the disease activity in either SWITCH or ORIGINATOR cohorts between Weeks 0 and 10. Similarly, no difference was found between cohorts at both prespecified time points. Moreover, no significant differences in CRP or FC concentrations were seen between W0 and W10 either in the SWITCH, or in the ORIGINATOR cohort [p &gt;0.05]. Adalimumab serum trough levels remained stable after the switch. No new safety signals were detected. Conclusions Our study confirmed that switching IBD patients from the originator adalimumab to a biosimilar compound [SB5] does not affect treatment efficacy.