ABSTRACT
Objectives: To evaluate the safety and immunogenicity of CoronaVac and ChAdOx1 vaccines against SARS-CoV-2 in patients with Rheumatoid Arthritis (RA). Method(s): These data are from the 'SAFER (Safety and Efficacy on COVID-19 Vaccine in Rheumatic Diseases)' study, a Brazilian multicentric longitudinal phase IV study to evaluate COVID-19 vaccine in immunomediated rheumatic diseases (IMRDs). Adverse events (AEs) in patients with RA were assessed after two doses of ChAdOx1 or CoronaVac. Stratification of postvaccination AEs was performed using a diary, filled out daily. The titers of neutralizing antibodies against the receptor-biding domain of SARS-CoV-2 (anti-RBD) were measured by chemilumine scence test after each dose of immunizers. Proportions between groups were compared using the Chi-square and Fisher's exact tests for categorical variables. Clinical Disease Activity Index (CDAI) before and after vaccination was assessed using the McNemar test. Result(s): A total of 188 patients with RA were included in the study, most of them were female. CoronaVac was used in 109 patients and ChAdOx1 in 79. Only mild AEs were observed. The more common AEs after the first dose were pain at injection site (46,7%), headache (39,4%), arthralgia (39,4%) and myalgia (30,5%), and ChAdOx1 had a higher frequency of pain at the injection site (66% vs 32 %, p alpha 0.001) arthralgia (62% vs 22%, p alpha 0.001) and myalgia (45% vs 20%, p alpha 0.001) compared to CoronaVac. The more common AEs after the second dose were pain at the injection site (37%), arthralgia (31%), myalgia (23%) and headache (21%). Arthralgia (41,42 % vs 25 %, p = 0.02) and pain at injection site (51,43% vs 27%, p = 0.001) were more common with ChAdOx1. No patients had a flare after vaccination. The titers of anti-RBDafter two doses of ChAdOx1 were higher compared to two doses of CoronaVac (6,03 BAU/mL vs 4,67 BAU/mL, p alpha 0,001). Conclusion(s): The frequency of local adverse effects, particularly pain at injection site, was high. AEs were more frequent with ChAdOx1, especially after the first dose. The use of the immunizers dis not change the degree of inflammatory activity of the disease. In patients with RA, ChAdOx1 was more immunogenic than CoronaVac. .