Effectiveness of tumor necrosis factor α inhibitors and their concentration and immunogenicity: features in various immune-mediated diseases

Abstract

Aim. To compare the concentration and immunogenicity of TNF-α inhibitors (TNFi) and their relationship with efficacy in patients with rheumatic diseases (RD) and inflammatory bowel diseases (IBD).Materials and methods. The study included 104 patients with RD (48.1%) and IBD (51.9%) who received infliximab (INF, 30.8%), adalimumab (ADA, 38.5%) and certolizumab pegol (CZP, 30.8%). We assessed the efficacy of the drug, trough concentration of TNFi and the level of antibodies. In 30 patients, the concentration of TNFi and the level of antibodies were assessed twice with an interval of 15 [13; 17] months.Results. TNF-α inhibitors were effective in 77 (74%) patients. In the group of IBD and RD, the incidence of inefficiency was 33.3% and 18.0%, the ineffectiveness of CZP was found only in IBD group (p = 0.024). A low concentration of TNFi was detected at the first visit in 29 (53.7%) patients with IBD and 24 (48.0%) with RD, at the second visit in 4 (36.4%) patients with IBD and 9 (47.4%) with RD. In all patients with RD who did not respond to IFN and CZP, the subtherapeutic concentration was determined (p = 0.047), in the IBD group – only in 64.3% cases (p > 0.050). At the first visit, antibodies to TNFi were found in 24 (23.1%) patients, at the second visit in 7 (23.3%) exclusively in the RD group (p = 0.019), in 5 of them repeatedly. The formation of Ab was associated with 27.8% of cases of escape of the effect of TNF-α in IBD and 22.2% of cases of ineffectiveness in RD (p > 0.050).Conclusions. The incidence of TNF-α efficacy did not differ between RD and IBD, CZP ineffectiveness was observed exclusively in patients with IBD. In patients with RD, a significant relationship was found between ineffectiveness and low concentration of TNFi. The frequency of Ab formation did not differ between the groups of diseases.