BIVALENT MRNA COVID-19 VACCINE BOOSTER DOES NOT INCREASE THE RISK OF FLARE IN RHEUMATOID ARTHRITIS PATIENTS UNDER REAL LIFE SETTING – DATA FROM SAFER STUDY

Background: Patients with immune-mediated rheumatic diseases (IMRDs) have been prioritized for COVID-19 vaccination to mitigate the infection severity risks. Individuals with rheumatoid arthritis (RA) are at a high risk of severe COVID-19 outcomes, especially those under immunosuppression or with comorbidities. In late 2022, the SARS-CoV-2 omicron BA.5 sublineage accounted for most of the sequenced viral genomes worldwide. Bivalent mRNA vaccines contain an ancestral strain component of the new coronavirus plus an updated component of the omicron BA.4 and BA.5. Since February 2023 a single bivalent mRNA vaccine booster dose has been recommended by the Brazilian Ministry of Health for adults who have completed a primary vaccination series and were at high risk of severe disease. However, few studies in the literature assessed the influence of the COVID-19 bivalent vaccine in the composite disease activity indices in patients with RA. Objectives: Evaluate the safety and the influence in the disease activity of a single bivalent mRNA vaccine booster against SARS-CoV-2 in patients with RA. Methods: These data are from the study “Safety and Efficacy on COVID-19 Vaccine in Rheumatic Diseases (SAFER),” a multicentric observational study that evaluate COVID-19 vaccine in IMRDs in Brazil. This analysis included adults meeting the ACR/EULAR (2010) classification criteria for RA from public’s healthcare centers, undergoing clinical-laboratorial assessments, and having their clinical disease activity indices (CDAI) scores calculated upon study inclusion and 28 days after de vaccination. Adverse events following the vaccination (AEs) were collected from all patients using a diary, filled out daily and returned at the end of 28 days after the booster dose. The Disease activity accessed before and after vaccination was compared using the McNemar test. For all tests, a statistical significance level of 5% and a confidence interval of 95% were used. Results: Of a total of 188 RA patients followed in the study during its primary vaccination schedule, 48 received the bivalent booster and were include in this sub-analysis. Most of them were female (95%), with mean BMI of 27 and an average age of 51 years. The most common comorbidity was hypertension (43%) and obesity (12 %). Only mild and transitory AEs were reported. The more common AEs (Table 1) were pain at the injection (60%), headache and Swelling around the injection site (31%), arthralgia (27%), fatigue (18%), fever (14%), myalgia (14%), nausea (10%) and dizziness (8%). The CDAI were evaluated in 38 individuals. No statistical difference was observed in the proportion of patients achieving treat to target goals (remission or low disease activity) before and after bivalent booster (Table 2). Conclusion: In general, the majority of AEs reported after bivalent COVID-19 booster were mild, similar to the previous data from monovalent immunizing in patients with RA. In the short period of observation, this vaccine did not increase the risk of flare in patients with RA. REFERENCES: [1] Tavares AC, de Melo AK, Cruz VA, de Souza VA, de Carvalho JS, Machado LL, et al. Guidelines on COVID-19 vaccination in patients with immune-mediated rheumatic diseases: a Brazilian Society of Rheumatology task force. Adv Rheumatol. 2022;62:3. Acknowledgements: NIL. Disclosure of Interests: None declared. DOI: 10.1136/annrheumdis-2024-eular.1582 Keywords: Vaccination/Immunization, Real-world evidence, Epidemiology Citation: , volume 83, supplement 1, year 2024, page 1573Session: Rheumatoid arthritis (Publication Only)

Vaccination/Immunization, Real-world evidence, Epidemiology