ABSTRACT
BACKGROUND AND AIMS: response to the SARS-CoV-2 vaccine can be altered in patients with immune-mediated diseases, such as inflammatory bowel disease, and in patients under immunosuppressive treatment. The aims of this study were to evaluate the serologic response to the SARS-CoV-2 vaccine in patients with inflammatory bowel disease, to analyze the influence of immunosuppressive drugs on response, and to describe any adverse events in this population. METHODS: this was a prospective study that included adult patients with inflammatory bowel disease. Baseline characteristics, concomitant treatments and previous COVID-19 symptoms were collected. Patients underwent serological testing before the first and after the second vaccine dose. RESULTS: a total of 265 patients were consecutively included. Patients received one of the following vaccines: messenger RNA vaccines from Pfizer/BioNTech and Moderna; and adenovirus vaccines from AstraZeneca and Janssen. All adverse events were mild, and the most frequent was injection site pain in 141 (86 %) patients. The seroconversion rate according to the treatment that patients were receiving was: 100 % for those without treatment, 92.5 % for patients treated with mesalazine, 90.3 % for those receiving immunomodulators, 88.9 % for patients with biological monotherapy and 92.5 % for patients on combined treatment. The generation of antibodies according to the vaccine administered was: Pfizer 92.9 %, Moderna 93.3 %, AstraZeneca 98.4 %, and Janssen 12.5 %. CONCLUSION: the antibody response after vaccination against SARS-CoV-2 is high in patients with inflammatory bowel disease. However, patients treated with immunosuppressive or biologic drugs had a lower response. Adverse events were frequent, but not serious.