Risk factors for anti-infliximab antibody formation among patients with inflammatory bowel disease
Authors: Abdoh Qusay , Kittaneh Ameer , Rabi Razan , Dweikat Alaa , Darwish Abdalaziz , Najajra Duha , Awwad Mahdi , Rajab Islam , Yaghmour Raghad , Alnees Mohammad 
Published: August 2024

Introduction: Infliximab (IFX) is an effective therapy for inflammatory bowel disease (IBD), but it may be associated with a high rate of primary and secondary failure. Approximately 30% of patients lose their response. One loss of response to anti-drug antibody (ADA) development is the most common cause of this loss. Objective: This study aims to demonstrate the incidence of antibody formation against infliximab when used to treat inflammatory bowel disease (IBD) and risk factors that may be associated with its formation, to find if there are correlations between antibody formation and patient characteristics, other co-medication, infliximab level, doses, duration, etc., and the subsequent correlation of antibody formation to Primary nonresponse, Secondary failure, Maintained response, and finally, to assess the overall clinical impact on the patients. Methods: A retrospective study included 61 participants who were treated with Infliximab (IFX) for inflammatory bowel disease and received follow-up at... Patients were recruited, and relevant demographic, clinical, and laboratory data were recorded from patients’ files, themselves, or the patient's family. as the antibody level was drawn for all patients, and therefore those with positive antibodies who met our criteria entered the exposure group, while the negative patients were in the non-exposure group. Results: There were 61 patients with IBD under infliximab therapy; 82% had Crohn's disease, and the rest had ulcerative colitis. Patient factors significantly associated with lower maintenance infliximab doses include age, smoking, aminosalicylates, and secondary non-response. Those of younger ages were more likely to develop infliximab-anti-drug antibodies (IFX-ADA) (OR, 95% CI; 1.12,1.007-1.25), and those who needed the use of amino-salicylates showed more tendency to develop IFX-ADA (OR, 95% CI; 0.03,0.01-0.74), AS 11.8% of participants with negative antibodies had used amino-salicylates compared to the other group, in which 3.7% of them used this. Higher doses (342.3 ± 94.54 mg) helped to obtain a better outcome by reducing the prevalence of ADA formation. Conclusion: IFX-ADA is significantly influenced by maintenance infliximab dose, age, smoking, aminosalicylates, and secondary non-response. There should be a decreasing IFX dose interval strategy. Aminosalicylates may help reduce the formation of IFX-ADA. Key messages of your article: Infliximab (IFX) is an effective therapy for inflammatory bowel disease (IBD), but it may be associated with a high rate of primary and secondary failure. This study aims to demonstrate the incidence of antibody formation against infliximab when used to treat inflammatory bowel disease (IBD) and the risk factors that may be associated with its formation to assess the overall clinical impact on patients. There should be a decreasing IFX dose interval strategy and Higher starting doses that may improve outcomes for IFX-treated patients with Crohn's disease and ulcerative colitis. Aminosalicylates may help reduce the formation of IFX-ADA.