PATIENTS WITH INFLAMMATORY BOWEL DISEASES HAVE IMPAIRED ANTIBODY PRODUCTION AFTER ANTI-SARS-COV-2 VACCINATION, ESPECIALLY THOSE ON ANTI-TNFα OR COMBINATION TREATMENT OF BIOLOGICS PLUS IMMUNOMODULATORS: RESULTS FROM A PANHELLENIC REGISTRY

ABSTRACT

Background: Patients with inflammatory bowel diseases (IBD) are commonly treated with immunosuppressive agents. Following the novel corona virus (SARS-CoV-2) pandemic, these patients received early the currently EMA approved vaccines. Data on efficacy and safety of SARS-CoV-2 vaccination on this population are lacking. Methods: Greek IBD patients, from 10 tertiary referral centres, who had completed the initial vaccination protocol with the available anti-COVID-19 vaccines (BNT162b2, mRNA-1273, Ad26.CoV2.S, ChAdOx1) at least two weeks before enrolment, were prospectively studied. Demographic and safety data were collected and blood samples were drawn for serum Anti-S1 IgG measurement [Euroimmun Anti-SARS-CoV-2 QuantiVac ELISA (IgG)]. Results: In total 403 IBD patients (59% Crohn's disease, median age 45 years, 53% male) and 124 healthy controls (HC) were included (Table 1). Antibody testing was conducted after a median of 31 (IQR, 23-46) days post-vaccination. Following a full vaccination regimen, 98% of IBD patients seroconverted (anti-S1 IgG³11 RU/ml). In total, IBD patients had lower anti-S1 levels than HC (RU/ ml 108 vs 133 RU/ml, P=0.00009) Administration of mRNA vaccines resulted in higher seroconversion rates and higher antibody titers than viral vector ones (98.6% vs 93.6%, P= 0.02 and 111.2 RU/ml vs 76 RU/ml, P<0.0001, respectively). Treatment with vedolizumab monotherapy was associated with higher antibody levels than anti-TNFα or ustekinumab monotherapy (P=0.02 and P=0.03). Longer timing between vaccination and antibody measurement was independently associated with impaired vaccine response. In multivariable analysis, specifically in mRNA-vaccinated cohort, older age, anti-TNFα treatment and treatment with biologics plus IMMs were significantly associated with lower antibody response (P=0.01, P=0.008, and P=0.02 respectively). Patients with prior COVID-19 infection showed numerically higher levels of antibodies. All vaccines were safe in IBD patients. Conclusions: Patients with IBD have high seroconversion rates to anti-SARS-CoV-2 vaccines. However, they demonstrate impaired antibody responses compared to HC. Patients receiving viral vector vaccines, and those on anti-TNFα or combination treatment may have further response impairment and it is important to consider booster vaccination in those low-response groups. (Table Presented)