SARS-CoV-2 vaccination in inflammatory bowel disease (IBD) patients - does treatment for IBD negatively affect SARS-CoV-2 antibodies? A single-centre, prospective study.

Introduction: Inflammatory bowel disease (IBD) patients use a wide variety of immunosuppressive drugs, including biologics, but their effect on SARS-CoV-2 vaccine antibody levels remains a mystery.

Aim: We analysed whether the drugs used in the treatment of IBD patients could affect the concentration of SARS-CoV-2 antibodies.

Material and methods: This is a prospective, single-centre evaluation of the persistence of SARS-CoV-2 antibodies after vaccination at various time points: every 2 months throughout the 6^th month after the first dose.

Results: We included a total of 346 vaccinated IBD patients in the study. A negative correlation between antibody level and time from full vaccination was confirmed for the following types of therapy: infliximab (rho = -0.32, p < 0.001), adalimumab (rho = -0.35, p = 0.025), and vedolizumab (rho = -0.50, p < 0.001). In the case of other, long-term drug administration, a negative correlation between antibody level and time from full vaccination was confirmed for mesalazine (rho = -0.35, p < 0.001), budesonide (rho = -0.58, p = 0.004), systemic glucocorticoids (rho = -0.58, p < 0.001), and azathioprine (rho = -0.44, p < 0.001).

Conclusions: Due to the immunosuppressive and biological treatment, IBD patients are exposed to a shorter persistence of SARS-CoV-2 antibodies and require booster doses. The role of gastroenterologists in educating patients about the need to continue SARS-CoV-2 vaccination remains crucial.