P519 Switching from reference infliximab to CT-P13 in patients with inflammatory bowel disease: Multicentre study at 12 months results

Abstract

Background: Infliximab have changed the natural history of inflammatory bowel diseases (IBD). However, with the advent of biosimilar treatment such as CT‐P13 promises to improve availability of biological therapy. Nowadays switching data are currently limited. Here, we assess the effectiveness and safety of switching to CT‐P13 from infliximab reference product (RP) in patients with IBD. Methods: This was a multicentre prospective observational study conducted at the Virgen Macarena Hospital and Juan Ramon Jimenez Hospital (Seville‐Huelva, Spain) from March 2015 to February 2016 in patients with Crohn's disease (CD) and ulcerative colitis (UC). All patients were switched from infliximab RP (RemicadeR) to CT‐P13 treatment and followed for up to 12 months. The efficacy endpoint was the change in clinical response assessed at 0 and 12 months, according to the Harvey‐Bradshaw score and partial Mayo score, and C‐reactive protein (CRP) for patients with CD and UC, respectively. Results: A total of 167 patients with IBD (116 with CD and 51 with UC) were included. The Baseline demographics according to the Montreal Classification are shown in Figure. Basal remission 87.4% (146 of 167), 12 months post switch 71.7% (109 of 152). Loss of efficacy at 12 months was 15.7%. 9% of patients discontinued CT‐P13 during follow‐up. CD patient group 88.8% (103 of 116) of patients with CD were in remission at the time of the switch and 69.7% were in remission at 12 months (P > 0.05. In total, 94.0% (109 of 116) of patients with CD completed 12 months of follow‐up. The HB score showed significant changes over the 12‐month period (median HB score: 1 [0‐1] vs. 1 [0‐2] (p = 0.001. No significant changes in median CRP levels were observed at 12 months (p = 0.49). UC patient group 84.3% (43 of 51) of patients with UC were in remission at the time of the switch and 76.7% were in remission at 12 months (p > 0.05). In total, 84.3% (43 of 51) of patients with UC completed 12 months of follow‐up. No significant changes in the median partial Mayo score (p = 0.87) were observed at 12 months. Significant changes in the median CRP level were observed over the same period (0.8 [0‐4] vs. 0.23 [0‐0.58]) (p = 0.003). Serious adverse events related to medication were reported in 12 of 167 (7.2%). Conclusions: Switching from infliximab RP to CT‐P13 is safe and efficacious at 12 months. Loss of efficacy at 12 months was 15.7%.