P489 Rescue treatment with original versus biosimilar infliximab in biologic-naïve patients with moderate-severe Ulcerative Colitis and corticosteroid failure

Muñoz-Villafranca, C.(1);Ogueta, M.Á.(2);Ramírez de la Piscina, P.(2);Álvarez-Herrero, B.(2);Loizate, A.(3);Gómez-Zabala, J.M.(3);De La Maza-Ortiz, S.(1);Aresti, U.(4);Gorostiza, I.(4);Arreba, P.(1);Irigoyen, M.(5);Ortiz de Zárate, J.(1);

(1)Hospital Universitario de Basurto, Gastroenterology Department, Bilbao, Spain;(2)Hospital Universitario Araba, Gastroenterology Department, Vitoria, Spain;(3)Hospital Universitario Basurto, Surgery Department, Bilbao, Spain;(4)Hospital Universitario Basurto, Investigation Department, Bilbao, Spain;(5)Hospital Universitario Príncipe de Asturias, Internal Medicine Department, Alcalá de Henares, Spain


Infliximab is effective as rescue therapy in moderate-severe Ulcerative Colitis (UC).  Subsequently, a biosimilar of infliximab has been approved for the same indications, as its effectiveness is considered similar to the original infliximab. Our aim was to analyse the colectomy rate and the efficacy of original infliximab (Remicade®) versus biosimilar infliximab (Inflectra®) in patients with moderate-severe UC who failed to respond to intravenous corticosteroids.


We performed a retrospective and observational study in two hospitals in the Basque Country. All patients hospitalised between 2010-2020 with moderate-severe UC, without response to intravenous corticosteroids and rescue treatment with infliximab were consecutively included. Two cohorts were established: the first one from 2010 to 2015 in patients treated with Remicade®, and the second one from 2015 to 2020 in patients with Inflectra®. We assessed all patients that had received at least one dose of infliximab. Patients were followed for a period of one year until loss of response or colectomy. Early colectomy is the surgery performed until week 12, and late colectomy between week 12 and one year. At the moment of hospitalisation all patients were clinically and endoscopically evaluated by Mayo Score. The clinical response was assessed in week 14 and 52.


A total of 85 patients were evaluated, 53 (64.4%) in Remicade® group and 32 (37.6%) in Inflectra® group. 21.17% (18/85) of the patients had a colectomy in one year. 77.7% of the colectomies took place in the first 12 weeks (14/18, 7 patient in each group). Rates of early (13.8% vs 21.9%, p=0.297) and late colectomy (17% vs 28.1%, p=0.223) showed a numerical but non-statistically significant difference in favour of Remicade®.

Transfusion (OR=4.20, IC 95% [1.38-12.77], p=0.011) and the presence of cytomegalovirus in the colonic mucosa (OR=4.07, IC 95% [1.31-12.63], p=0.015) were univariate predictors of colectomy. A statistically significant difference was found in clinical remission at week 14 (49.1% vs 25%, p=0.040) but not at week 52 (73.7% vs 50%, p=0.074) in patients with Remicade® versus Inflectra®. Neither clinical activity nor mucosa activity showed relationship with risk of colectomy.


1. The rescue therapy with infliximab in patients with moderate-severe Ulcerative Colitis who failed to respond to intravenous corticosteroids could show a favourable trend for Remicade® against Inflectra®. However, further research is needed to confirm it.
2. The need of transfusion and the presence of cytomegalovirus in the colonic mucosa could be predictive factors of colectomy.