P786 Evaluation of the efficacy and safety of the use of subcutaneous infliximab in the treatment of inflammatory bowel disease in naïve patients

Abstract

Abstract Background The use of intravenous (IV) infliximab in inflammatory bowel disease (IBD) is an established treatment with a demonstrated safety and efficacy profile. Subcutaneous (SC) infliximab is currently available, showing comparable results in disease maintenance, but lacking studies in naïve patients. This study aims to determine whether initial treatment with SC infliximab is as effective and safe in real clinical practice. Methods This is a single-center observational study that included patients with clinically active IBD who directly initiated SC infliximab after IV induction (IV 5 mg/kg 0-2 weeks and SC 120 mg/2 weeks at week 6). The primary objective of the study was to evaluate the response to SC treatment at 3 and 9 months in patients naïve for infliximab. Secondary objectives included the need for intensification, rescue treatments (corticosteroids, change of biologic or surgery), the occurrence of adverse effects and pharmacokinetic aspects (blood levels, development of antibodies to infliximab or ATIs). Clinical activity was assessed using the Harvey-Bradshaw Index (HBI) for Crohn's disease (CD) and Partial Mayo Score (PMS) for ulcerative colitis (UC). In addition, biochemical parameters (hemoglobin, albumin, C-reactive protein, and fecal calprotectin) were monitored. Results A total of 19 patients were included, 14 with CD and 5 with UC (Table 1). Among them, 16/19 had not received previous biological treatment and 3/19 had received another anti-TNF other than infliximab. They were followed at 3 (18/19) and 9 months (18/19) (Figure 1). Significant improvement (p<0.05) was observed in the parameters of clinical activity (6/18 persisting with mild-moderate activity at 9 months) and biochemical activity (fecal calprotectin). Infliximab levels were adequate at 3 (median 12; range 3.2-39) and 9 months (median 15.9; range 0.3-51). In total, 31.6% of patients (6/19) discontinued treatment: 1/19 due to mild acute urticaria at baseline, 2/19 due to the development of ATIs (one also developed lung abscesses requiring hospitalization) and 3/19 due to loss of secondary response requiring a change of biologic. Of the latter, one also needed treatment with oral corticosteroids. In none of the patients was the treatment intensified or surgery required. Conclusion Treatment with SC infliximab in naïve patients seems to be an effective and safe alternative with results comparable to IV infliximab in real clinical practice. In our 9-month study, clinical scores and fecal calprotectin improved significantly, with low immunogenicity rates. Only 31.6% of patients discontinued treatment due to adverse effects or loss of response. Table 1. Baseline characteristics of patients