In a case-control study with 632 patients with autoimmune diseases (5% with SLE), seroconversion rates after first dose of mRNA or adenoviral vector COVID-19 vaccines were significantly lower in patients than controls. 18 After the second vaccination ( em n /em ?=?125), seroconversion exceeded 80% in all patient treatment subgroups, except those treated with anti-CD20. response comparing SLE patients and controls. Other outcomes included reactogenicity, disease activity and predictors of antibody responses in patients with SLE. Results: Sixty-five SLE patients received 2 doses of COVID-19 vaccines (Comirnaty: 38; CoronaVac: 27) were recruited. Many of them were on systemic glucocorticoids (76%) and immunosuppressants (55%). At day 28 after the second dose of vaccines, 92% (Comirnaty: 100% vs CoronaVac: 82%, (%)47 (94)61 (93)36 (95)25 (93)1.000Type of vaccines:?Comirnaty, (%)37 (57)38 (59)?CoronaVac, (%)28 (43)27 (42)SLEDAI-2k2.9??2.02.8??1.73.0??2.40.625Anti-dsDNA, IU/ml177??179181??170171??1940.830Proteinuria, g/24-hour0.25??0.250.24??0.200.27??0.300.676Systemic glucocorticoids, (%)49 (75)29 (76)20 (74)0.836Prednisolone dosage, mg/day4.9??2.64.6??1.55.3??3.70.452Mycophenolate mofetil, (%)17 (26)11 (29)6 (22)0.543Azathioprine, (%)7 (11)4 (11)3 (11)1.000Cyclosporine A, (%)7 (11)4 (11)3 (11)1.000Tacrolimus, paederoside (%)5 (8)2 (5)3 (11)0.642Methotrexate, (%)1 (2)0 (0)1 (4)0.415 Open in a separate window SLEDAI-2k, Systemic Lupus Erythematosus Disease Activity Index 2000; SLE, Systemic lupus erythematosus. Immunogenicity Among the 65 patients with SLE, 60 (92%) experienced positive neutralizing antibody at 28?days paederoside after the second dose, while all healthy controls (100%) were sero-positive (p?=?0.058). Compared to controls, the neutralizing antibody level was significantly lower (mean 64.4??22.9% vs 83.0??18.0%, (%). Predictors of immunogenicity Univariate analyses showed that the use of mycophenolate mofetil was associated with significantly lower neutralizing antibody level (mean 52.1??20.7% vs 68.7??22.3%, value /th /thead AgeC0.022C0.425 C 0.3810.914Gender8.16C 7.39 C 23.70.296SLEDAI-2kC1.96C4.22 C 0.310.088Prednisolone dosageC2.01C3.66 – C0.37 0.018 Mycophenolate mofetilC15.2C24.4 – C6.0 0.002 Type of vaccines: Comirnaty28.820.1 C 37.5 0.001 Open in a separate window SLEDAI-2k, Systemic Lupus Erythematosus Disease Activity Index 2000. Conversation To our understanding, this is the first prospective study assessing the immunogenicity and security of inactivated and mRNA COVID-19 vaccines focusing on patients with SLE. We found an impaired antibody response in lupus patients compared to matched healthy population. Adverse reactions were common but all moderate and transient. There was no evidence of worsening of lupus disease control after vaccination in short term. Although higher disease activity appeared to be associated with lower antibody response, multivariate analysis revealed the impartial determinants were the immunosuppressive medications used, particularly systemic glucocorticoids and mycophenolate. mRNA vaccine induced a better humoral response but was associated with more reactogenicity compared to inactivated vaccine in lupus patients. Our results largely concur with the published literature on COVID-19 vaccines, mainly mRNA, in patients with ARD. A post-marketing study from a nationwide mass vaccination database ( em n /em ?=?596,618), which included 2.7% of participants with immunosuppression (definition and underlying disease not mentioned), reported that this mRNA vaccine was equally effective for a wide range of COVID-19 related outcomes. 16 In an initial research letter, the immunogenicity of mRNA COVID-19 vaccine in 123 patients with rheumatic diseases (20% with SLE) was reported. 17 After the first dose, 74% patients experienced a detectable antibody response. However, those on mycophenolate or rituximab were less likely to develop an antibody response ( em p /em ?=?0.001 and em p /em ?=?0.04, respectively). Of notice, only 27.3% of patients on mycophenolate experienced detectable antibody. FASLG In a case-control study with 632 patients with autoimmune diseases (5% with SLE), seroconversion rates after first dose of mRNA or adenoviral vector COVID-19 vaccines were significantly lower in patients than controls. 18 After the second vaccination ( em n /em ?=?125), seroconversion exceeded 80% in all patient treatment subgroups, except those treated with anti-CD20. Another multicenter study showed that this seropositive rate in patients with ARD ( em n /em ?=?686, 15% with SLE) was 86% paederoside after 2 doses of mRNA vaccine which was significantly lower than controls, and the risk factors for reduced immunogenicity included older age and treatment with glucocorticoids, mycophenolate, rituximab and abatacept. 19 In a study of 264 ARD patients (10% with SLE) without control group, 86% of patients mounted humoral response after second dose of mRNA vaccine and 59% of those with unfavorable response were treated with B cell-depleting brokers. 20 Similarly, in another uncontrolled study, 89% of patients with SLE ( em n /em ?=?54) were able to mount a serological response, while only 24% of those on rituximab had paederoside detectable antibodies. 21 With regard to security, a web-based survey of 696 patients with SLE showed that 45% and 53% of respondents reported side effects after first and second dose of vaccines respectively with no difference according to vaccine types (Pfizer-BioNTech 57%, Sinovac 22%, AstraZeneca 10% and Moderna 8%). 12 Only 3% of.