Efficacy and Safety of Infliximab Tolerance Induction in Patients with Inflammatory Bowel Diseases who Experienced Acute Infusion Reactions.

BACKGROUND AND AIMS: One of the reasons for the failure of infliximab (IFX) is immediate hypersensitivity reactions (IHR). We aimed to report the efficacy and safety of a tolerance induction protocol in inflammatory bowel diseases (IBD) patients who had previously experienced IHR during IFX infusions.

PATIENTS AND METHODS: We reported all cases of IBD patients who had previously experienced IHR due to IFX and who were submitted to a standardized protocol of tolerance induction to IFX from 2010 to 2015.

RESULTS: IHR occurred in a majority of patients (69%) during the first 3 infusions and for half of them after a period of IFX withdrawn. Skin prick tests were negative and only 2 intradermal tests were positive. Basophil activation tests and antidrug antibody measurements were performed in 8 out of 16 patients and were positive in 3 and 4 patients respectively. Induction of tolerance was successful in 69% of patients and IFX was pursued with clinical efficacy > 1 year in 7 patients (44%). Allergologic investigations were not predictive of tolerance induction success.

CONCLUSION: A majority of IHR to IFX infusions occurred during the beginning or restarting of treatment and was related to a nonallergic hypersensitivity. Induction of tolerance to IFX is feasible and effective and may safely allow retreatment of IFX in almost 70% of IBD patients.