[Evaluation of efficacy and comparative frequency of adverse events in patients with ulcerative colitis receiving the original infliximab and its biosimilar. One year of observation].

Real - life data on the effectiveness and safety of biosimilar and biologic drugs licensed for treatment of inflammatory bowel diseases (IBD) is lacking. AIM: To investigate efficacy of original Infliximab (IFX) and its biosimilar in treating patients with ulcerative colitis (UC) and determine the frequency of adverse events during 1 year follow - up period. MATERIALS AND METHODS: Our cohort consisted of 98 ulcerative colitis patients, treated with original IFX and its biosimilar since December 2017 till December 2018 years. Original Infliximab was prescribed in 56 UC patients (57.1%) during 5 years and longer; 16 patients (16.3%) were switched to IFX biosimilar; 13 UC bio - naïve patients (13.3%) received original IFX, 29 (29.6%) patients - biosimilar IFX. In 14 patients (14.3%) original infliximab was rotated with biosimilar. We picked out 42 patients to assess efficacy of original IFX and biosimilar. RESULTS AND DISCUSSION: Twelve patients, received original IFX and 28 patients, treated with its biosimilar, showed significant clinical improvement by decreasing Mayo index from 9.7±0.4 and 10.2±0.2 points to 1.9±0.09 and 2.1±0.1 points, accordingly. Also we noticed positive change in laboratory markers - CRP decrease from 89.6±8.7 mg/l and 77.5±8.0 mg/l to 6.5±0.8 mg/l and 6.9±0.8 mg/l (p>0.05), albumin increase from 30.1±4.7 g/l and 29.6±3.6 g/l to 34.1±6.3 g/l and 32.8±5.9 g/l (p>0.05), increase of serum iron levels from 6.4±0.5 mcg/l and 7.1±0.65 mcg/l to 14.6±4.4 mcg/l and 15.9±5.1 mcg/l (p>0.05), hemoglobin increase from 104.7±9.8 g/l and 102.2±8.8 g/l till 124±11.3 g/l and 121±10.9 g/l (p>0.05), and fecal calprotectin decrease from 1680±134 mcg/g and 1720±126 mcg/g till 245.5±33.4 mcg/g and 230.5±29.8 mcg/g (p>0.05). During 1 year follow - up 12 UC patients, treated with original IFX and its biosimilar, developed adverse events. The majority of adverse events (n=8) were registered in patients, rotating administration of original IFX and its biosimilar. CONCLUSION: IFX biosimilar is effective as well as original IFX. Frequency of adverse events, occurred in patients, treated with original IFX, was comparable with adverse events frequency in patients, received biosimilar IFX. Frequency of adverse events was significantly higher in UC patients, rotating original IFX and its biosimilar.