Introduction: The immunogenicity of
SARS-CoV-2 vaccines in patients with
inflammatory bowel disease (IBD) on
biologic therapies is not well studied. The goal of this study was to measure the serological response to
BNT162b2 and
ChAdOx1 nCoV-19 vaccines in patients with IBD receiving different
biologic therapies. Methods: We performed a multi-center prospective study between 1 August 2021 and 15 September 2021. We measured the seropositivity of SARS-CoV-2
antibodies (SARS-CoV-2 IgG) and
neutralizing antibody concentrations in patients with IBD receiving
biologic therapies 4-10 weeks after their second dose or 3-6 weeks after their first dose of
BNT162b2 or
ChAdOx1 nCoV-19 vaccines. Results: A total of 126 patients were enrolled (mean age, 31 years; 60% male; 71%
Crohn's disease, 29%
ulcerative colitis). Of these, 92 patients were vaccinated with the
BNT162b2 vaccine (73%) and 34 patients with the
ChAdOx1 nCoV-19 vaccine (27%). In patients being treated with
infliximab and
adalimumab, the proportion of patients who achieved positive anti-SARS-CoV-2
IgG antibody levels after receiving two doses of the
vaccine were 44 out of 59 patients (74.5%) and 13 out of 16 patients (81.2%), respectively. In contrast, of those receiving
ustekinumab and
vedolizumab, the proportion of patients who achieved positive anti-SARS-CoV-2
IgG antibody levels after receiving two doses of the
vaccine were 100% and 92.8%, respectively. In patients receiving
infliximab and
adalimumab, the proportion of patients who had positive anti-SARS-CoV-2
neutralizing antibody levels after two-dose vaccination was 40 out of 59 patients (67.7%) and 14 out 16 patients (87.5%), respectively. On the other hand, the proportion of patients who had positive anti-SARS-CoV-2
neutralizing antibody levels were 12 out of 13 patients (92.3%) and 13 out of 14 patients (92.8%) in patients receiving
ustekinumab and
vedolizumab, respectively. Conclusions: The majority of patients with IBD who were on
infliximab,
adalimumab, and
vedolizumab seroconverted after two doses of SARS-CoV-2 vaccination. All patients on
ustekinumab seroconverted after two doses of
SARS-CoV-2 vaccine. The
BNT162b2 and
ChAdOx1 nCoV-19 SARS-CoV-2 vaccines are both likely to be effective after two doses in patients with IBD on biologics. Larger follow-up studies are needed to evaluate if decay of
antibodies occurs over time.