P784 Efficacy of ustekinumab in biologically naïve patients with Inflammatory Bowel Disease

In recent years, there are several new treatment options for inflammatory bowel disease (IBD). Tumour necrosis factor α inhibitors have been joined by novel advanced therapies (vedolizumab, ustekinumab (UST) and Janus kinase inhibitors). These drugs are mostly used as second-line treatments after tumor necrosis factor α inhibitors, with subsequent poorer efficacy. There are few data available on the efficacy of first-line treatment with UST. The aim of our study was to assess efficacy of UST in biologically naïve patients with IBD. All patients older than 18 years who had a confirmed diagnosis of IBD, treated in a tertiary IBD centre (University Medical Centre Ljubljana, Slovenia), who started first-line treatment with UST, were included in this retrospective cross-sectional cohort study. Demographics, clinical characteristics of patients, treatment persistence of UST, clinical disease activity scores, C-reactive protein (CRP), faecal calprotectin (FC), UST concentrations, and endoscopic scores were collected retrospectively in medical files. We determined a Kaplan-Meier curve of treatment persistence. We included 71 patients, 11 of which had ulcerative colitis and 60 had Crohn’s disease. Persistence of treatment with UST in biologically naïve patients is 88% at one year (Figure 1). Clinical remission was achieved in 57.7% of patients. Biochemical remission was achieved in 77.6% (CRP<5mg/ml) and 71.1% (FC<100mg/kg) of patients. Endoscopic remission (Mayo endoscopic score <2 in ulcerative colitis or absence of ulcers in Crohn’s disease) was achieved in 50.0% of patients. There was no significant difference (P>0.05) between the median serum concentrations of UST in the group of patients who achieved remission (clinical (5.86μg/ml), biochemical (5.93μg/ml based on CRP, 5.63μg/ml based on FC) and endoscopic (7.14μg/ml)) and who did not achieve remission (5.31μg/ml, 3.25μg/ml, 4.47μg/ml and 4.64μg/ml, respectively). Treatment of UST in biologically naïve IBD patients shows high treatment persistence with high biochemical and endoscopic remission rates. It appears that UST is more efficacious if used as first-line therapy compared to the use after other advanced therapies. Further prospective data are needed to confirm our findings.