Introduction: The response to SARS-CoV-2 vaccination of patients with inflammatory bowel disease (IBD) on immune-modifying therapies requires further investigation because previous studies indicate that patients on immune therapy might have decreased antibody concentrations.

Methods: We present the antireceptor binding domain antibody response over a period of 3 months in 217 patients with IBD who completed standard 2-dose SARS-CoV-2 mRNA vaccine series.

Results: Almost all (98.6%) IBD vaccine recipients had a positive antireceptor binding domain antibody response at least 3 months after vaccination. Decreased antibody titers at 3 months were seen in a subset of patients on antitumor necrosis factor-alpha. Approximately 10% of the participants with high-titer antibodies at 1 month had a decrease to low-positive titers at 3 months, which was mostly observed in those on combination therapy and antitumor necrosis factor-alpha monotherapy.

Discussion: Larger longitudinal studies are required to define the response in IBD population and its clinical impact.