Humoral response to Pfizer mRNA vaccine against SARS CoV2, in patients with autoimmune inflammatory rheumatic diseases and the impact on the rheumatic disease activity

Braun-Moscovici, Y.; Kaplan, M.; Markovits, D.; Giryes, S.; Toledano, K.; Tavor, Y.; Dolnikov, K.; Balbir-Gurman, A.

Abstract Background: The registration trials of mRNA vaccines against SARS CoV2 did not address patients with autoimmune inflammatory rheumatoid diseases (AIRD). Aims: To assess the humoral response to mRNA vaccine against SARS CoV2, in AIRD patients treated with immunomodulating drugs and the impact on AIRD activity. Methods: Consecutive patients treated at the rheumatology institute who received their first SARS-CoV-2 (Pfizer) vaccine were recruited to the study, at their routine visit. The patients were invited for serology test 4-6 weeks after receiving the second dose of vaccine. IgG Antibodies (Ab) against SARS COV2 virus were detected using the SARS-Cov-2 IgG II Quant (Abbott) assay Results: One hundred fifty-six consecutive patients (76% females) treated at a single rheumatology center (mean age (range) 59.1 (21-83) years), mean (range) disease duration 10.8 (1-55) years), were recruited to the study. Thirty-five percents of patients received conventional synthetic (cs)DMARDs only, 64% biological/targeted synthetic (b/ts) DMARDs, 34% received combined treatment with csDMARDs and b/tsDMARDs and 32% corticosteroids (mean dose(range) 5.8mg(2.5-20mg) prednisone). One hundred thirty-seven patients (88%) were seropositive for IgG Ab against SARS CoV2 virus (median 2832.5 AU/ml, range 58-29499). Nineteen (12%) patients had negative tests, 11/19 were treated with B cell depleting agents. The reported side effects of the vaccine were minor (muscle sore, headache, low grade fever). The rheumatic disease remained stable in all patients. Conclusions: The vast majority of AIRD patients developed a significant humoral response following the administration of the second dose of the Pfeizer mRNA vaccine against SARS CoV2 virus. Only minor side effects were reported and no apparent impact on AIRD activity was noted.