A170 ADVERSE EVENTS & SEROLOGICAL RESPONSES FOLLOWING SARS-COV-2 VACCINATION IN INDIVIDUALS WITH INFLAMMATORY BOWEL DISEASE

Abstract Background The rapid development and distribution of SARS-CoV-2 vaccines has raised concerns surrounding vaccine safety in immunocompromised populations, such as those with inflammatory bowel disease (IBD). Purpose We described adverse events (AEs) following vaccination IBD determined relationships between AEs to post-vaccination antibody titres. Method Individuals from a prospective cohort Calgary, Canada (n=670) who received 1st, 2nd, 3rd, and/or 4th dose (Pfizer-BioNTech, Moderna, AstraZeneca) were interviewed via telephone for using the Adverse Events Following Immunization form. Subsequently, we assessed injection site reaction specific AE outcome. Multivariable logistic regression models used assess association anti-SARS-CoV-2 spike protein (anti-S) levels within 1–12 weeks 3rd vaccination. Models adjusted age, sex, type, medications, prior COVID-19 infection. Additionally, evaluated risk flare 30 days chart review. Result(s) Table 1 describes individuals 1st (n=331), 2nd (n=195), (n=100) vaccine. reported 83.3% participants after dose, 79.1% 77.4% 67.0% dose. Injection (pain, redness, etc.) was most common (50.8% AEs), fatigue malaise (18.1%), headache migraine (8.6%), musculoskeletal discomfort (8.2%), fever chills (6.5%) also commonly reported. no associations anti-S concentration all doses. Age above 65 years associated decreased doses, while female sex mRNA type increased Prior infection, medication class not any Only one participant diagnosed severe requiring hospitalization: Immune thrombocytopenic purpura (ITP) Pfizer No cases occurred Image Conclusion(s) are generally mild become less each consecutive Antibody reactions. Females, under administered more likely experience an reaction. did predict Vaccination Please acknowledge funding agencies by checking applicable boxes below Other indicate your source funding; Helmsley Disclosure Interest A. Markovinovic: None Declared, M. Herauf: J. Quan: L. Hracs: Windsor: N. Sharifi: S. Coward: Caplan: Gorospe: C. Ma Grant / Research support from: Ferring, Pfizer, , Consultant of: AbbVie, Alimentiv, Amgen, Takeda, Speakers bureau R. Panaccione Janssen, Abbott, Arena, AstraZeneca, Boehringer Ingelheim, Bristol Myers Squibb, Celgene, Celltrion, Cosmos Pharmaceuticals, Eisai, Elan, Eli Lilly, Galapagos, Genentech, Gilead Sciences, GlaxoSmithKline, Merck, Mylan, Oppilan Pharma, Pandion Therapeutics, Progenity, Protagonist, Roche, Sandoz, Satisfai Health, Schering-Plough, Shire, Sublimity Theravance, UCB, Ingram: Kanji: G. Tipples: Holodinsky: Berstein D. Mahoney: Bernatsky: E. Benchimol: Kaplan