Written consent was from all participants before sampling. == Routine Laboratory Measurements and Autoantibody Analyses == Blood samples were collected from RA individuals as part of routine clinical screening. antibodies were measured by chemiluminescence. ESR (erythrocyte sedimentation rate) was recognized by ESR analyzer. C-RP (c-reactive protein) was recognized by immunoturbidimetry. NEUT% (percentage of Epothilone B (EPO906) neutrophils) and LYMPH% (percentage of percentage) were calculated by a calculation method. == Results == Compared with the HC group, the percentage of inhibition was significantly reduced RA individuals receiving two doses of vaccines. Vaccines-induced percentage of inhibition was the lowest in RA patients who had not been vaccinated. In total 80.77% of the HC group had a percentage of inhibition 20%, compared with 45.24% of vaccinated RA patients and 6.06% of unvaccinated RA patients. Spearman correlation analysis revealed that antibody responses to SARS-CoV-2 did not differ between RA patients according to their age and disease duration. Furthermore, the Epothilone B (EPO906) results showed that no correlation was found between the percentage of inhibition and indices for RA, including RF-IgA, IgG, IgM; anti-CCP antibody; ESR; C-RP; NEUT% and LYMPH%. == Conclusion == Our study showed inactivated vaccine-induced SARS-COV-2 antibody responses differ in RA patients and healthy subjects, emphasizing the importance of a third or fourth vaccination in RA patients. Keywords:COVID-19, inactivated SARS-CoV-2 vaccines, rheumatoid arthritis, neutralizing antibodies, immunogenicity == Introduction == Coronavirus disease 2019 (COVID-19) has progressed to a worldwide pandemic and posed enormous challenges to healthcare (1). Since January 2020, the computer virus has spread rapidly to large parts of China and other countries, which soon captured global attention with the pathogen identified as SARS-CoV-2. According to new data released by WHO (World Health Business) on 18 March 2022, there have been 464,809,377 confirmed cases, and approximately 6,062,536 people have died from COVID-19. Currently, the COVID-19 pandemic is still a global challenge as there are continuous genetic variations of the SARS-CoV-2 genome and mutations in the S protein are increasingly reported (2). A new variant of SARS-CoV-2 (Omicron) has more than 50 mutations and is spreading rapidly with an average doubling time of 2 days, and has taken over globally including dividing into subvariants with even more diversity and transmissibility (3). Vaccination may be the most efficient strategy, which is crucial for controlling the COVID-19 pandemic. According to data released by the Chinese National Health Commission rate on March 19, 2022, more than 3.22 billion COVID-19 vaccine doses have been administered around the Chinese mainland (http://www.nhc.gov.cn/xcs/yqjzqk/list_gzbd.shtml), and nearly 1. 24 billion people have been fully vaccinated. Rheumatoid arthritis (RA) is usually a chronic autoimmune IDH1 and inflammatory disorder, which occurs when your immune system attacks Epothilone B (EPO906) your own body’s tissues by mistake. RA typically affects the joints, but the systemic inflammatory process can also cause damages on a wide variety of body systems, including the skin, eyes, Epothilone B (EPO906) lungs, heart, and blood vessels (4). Previous studies have shown that he immunogenicity of the pneumococcus vaccine is usually reduced Epothilone B (EPO906) in RA patients treated with methotrexate (5). Hepatitis B computer virus vaccines may be less immunogenic in RA patients receiving anti-TNF therapy (6). A study has found impaired antibody responses to the BNT162b2 messenger RNA coronavirus disease 2019 vaccine in RA patients (7). Certain therapies (anti-TNF, anti-IL17, anti-IL6, anti-IL12/23) did not appear to affect seroconversion rates, whereas anti-CD20 and anti-CTLA-4 resulted in poorer responses in rheumatic and non-rheumatic patients treated with immunosuppressive brokers (7,8). The COVID-19 pandemic created concerns about immunosuppression in autoimmunity (9). Although vaccination is recommended for RA patients, they are still anxious about getting vaccinated as the patients with autoimmune disease showed an attenuated humoral response to SARS-CoV-2 vaccination (10), and research showed that immunosuppressed status is usually associated with an increased risk of COVID-19 contamination despite vaccination (11). However, these findings are mostly based on mRNA vaccines (12). It is still unclear whether disease-modifying anti-rheumatic drug (DMARD) treatment can affect inactivated SARS-CoV-2 vaccine-induced seropositivity, which are main types of vaccines used in China. In this study, we evaluated the safety and immunogenicity of inactivated SARS-CoV-2 vaccine in RA patients and provided further evidence for RA patients to receive inactivated SARS-CoV-2 vaccines. == Materials and Methods == == Study Design == RA patients and healthy controls received two doses of vaccine mainly between May and August 2021. Blood samples were collected around December 2021. The study populace consisted of 75 RA patients and 26 healthy controls (HC), the baseline characteristics of whom were shown inTable 1. Forty-two of 75 patients (56%) received two doses of inactivated SARS-CoV-2 vaccines, and all the HC group were injected.