P017 Increased Level of Immunoglobulin G in the Development of Adverse Reactions in Patients With Ulcerative Colitis.

Background: Goal: To identify the relationship between the level of immunoglobulins G and E and the development of adverse reaction (AR) in patients with ulcerative colitis (UC) receiving original infliximab (IFХ) and infliximab biosimilar (BS).

Methods: 35 UC patients with moderate to severe course of the disease (according to Truelove-Witts) who received maintenance therapy with IFХ at a standard dose of 5 mg/kg of body weight for a year were retrospectively analyzed. There were 16 men (45.7%), 19 women (54.3%). The average age is 34±4.2 years. The duration of the anamnesis was from 3 to 7 years. Patients were divided into 3 groups depending on the development of AR and the received biological drug, without taking into account concomitant anti-inflammatory therapy. The 1st group (n=14) alternated the introduction of the original IFХ and its BS; The 2nd group (n=7) consisted of patients alternating between the original IFХ and BS, in whom AR was registered; the 3rd group (n=14) received BS by one trade name. Using enzyme immunoassay, the level of immunoglobulins in the groups of patients was assessed.

Results: In the 1st and 3rd groups, AR was not observed. AR in 2nd group was characterized by: bronchospasm 3 (42.8%), Quincke's edema 1 (14.3%), urticaria 1 (14.3%), rhinitis 1 (14.3%), anaphylactic shock 1 (14.3%). In patients of 1st group, the level of IgE is 44.8 ± 5.1 IU/ml, IgG is 16.5 ± 1.7 g/l. In 2nd group -IgE-44.5 ± 11.7 IU / ml, IgG-26.1 ± 2.1 g/l, while in patients in group 3-IgE - 31.5 ± 3.04 IU/ml, IgG - 9.46 ± 1.01 g/l. It was reliably established that the highest level of IgG was observed in the 2nd group, while in the 3rd group it was minimal (p < 0.05). The IgG level in 1st group is higher than in 3rd group, although in both groups the IgG level was within the reference values. In all groups, the IgE value remained normal.

Conclusion: AR on the background of therapy with IFL and biosimilars are not associated with an increase in the level of IgE, but are caused by an increase in the level of IgG. The alternation of the original drug and the biosimilar increases the risk of developing AR due to increased IgG levels. Treatment with a biosimilar by one trade name does not increase the risk of developing AR.