Subcutaneous Infliximab in Refractory Crohn's Disease Patients: A Possible Biobetter?

Background A subcutaneous formulation of infliximab (IFX-SC) approved to treat patients with inflammatory bowel disease may offer improved efficacy versus intravenous infliximab.Methods Patients with refractory Crohn's disease (CD, n = 32) previously treated unsuccessfully with at least 2 biologics were treated with IFX-SC and followed from baseline at Week 0 (W0) to Week 30 (W30). The study's primary endpoint was the treatment's persistence at W30, while secondary goals included the analysis of serum infliximab trough levels (TL IFX), dynamics of anti-IFX antibodies (ATIs), and clinical, serum and fecal markers of CD activity during IFX-SC treatment.Results Midterm treatment persistence with the continuation of treatment after W30 was 53%. TL IFX median values showed rapid, significant upward dynamics and exceeded 15.5 mu g/mL at W30, whereas median ATI levels significantly declined. Among ATI-negative patients at W0 (n = 15), only one showed IFX immunogenicity with newly developed ATIs at W30. Among ATI-positive patients at W0, ATI seroconversion from ATI-positive to ATI-negative status was observed in 10 of 17 patients (58.8%). Patients who had continued IFX-SC treatment at W30 showed significant decreases in C-reactive protein (P = .0341), fecal calprotectin (P = .0002), and Harvey-Bradshaw index (P = .0029) since W0.Conclusions Patients with refractory CD previously treated with at least 2 biologics exhibited clinically relevant improvement with IFX-SC, which showed less immunogenic potential than IFX-IV and highly stable TL IFX. Infliximab is currently administered intravenously to treat Crohn's disease patients. In this study, subcutaneous administration of infliximab was found to have advantages for refractory CD patients, including stable, consistently higher levels of the drug and significantly lower immunogenicity. Graphical Abstract