Luciana Parente Costa Seguro, Paulo Rossi Menezes, Clovis Almeida da Silva, C. G. S. Saad, Ana Cristina de Medeiros Ribeiro, Léonard de Vinci Kanda Kupa, Samuel Katsuyuki Shinjo, Rosa Maria Rodrigues Pereira, Ana Marli Christovam Sartori, Esper G. Kallas, Sandra Gofinet Pasoto, Eloisa Bonfa, Danieli Castro Oliveira de Andrade, Emily Figueiredo Neves Yuki, Alberto José da Silva Duarte, Filipe Waridel, Percival D. Sampaio-Barros, E Sabino, Ricardo Fuller, Nádia Emi Aikawa, Juliana Miranda de Lucena Valim, Leila Antonangelo, and Tatiana do Nascimento Pedrosa
Background: Limited information is available on response to Covid-19 vaccines in autoimmune rheumatic disease patients(ARD) previously exposed to the SARS-CoV-2. We compared the dynamics of vaccine induced antibody production after immunization with CoronaVac in SARS-CoV-2 - seropositive ARD patients(ARD+) with two age/sex balanced groups: SARS-CoV-2 naive ARD patients(NAIVE-ARD) and SARS-CoV-2-seropositive control group(CTRL+). Methods: Participants of this phase 4 prospective controlled study were vaccinated with two doses of CoronaVac(28-days interval). Primary objective was immunogenicity dynamics evaluated by median neutralizing activity(NAb-activity)/anti-SARS-Cov-2 ln(IgG) titers[ln(IgG)] from D0-D28 and from D28-D69. Secondary objectives included safety and other immunogenicity parameters. Findings: Disease and therapy were similar in ARD+ and NAIVE-ARD groups(p>0·05). A comparable dynamics was observed for ARD+ and CTRL+ with a plateau increase occurring from D0-D28[ARD+, NAb-activity:59·1% to 81·8%, mean difference -12·1%,p=0·002 and anti-S1/S2-GMT:52·3 to 128·9, ln(IgG) mean difference -0·9,p 0·999) and anti-S1/S2-GMT(p 0·999 and D69:-12·3%,p=0·167/0·32%,p=0·258 with minor difference at D28:-13·6%, p=0·067/-0·45,p=0·006. Interpretation: ARD+ patients mount a robust plateau response after a single dose of inactivated SARS-CoV-2 vaccine, independent of pre-existing ARD/therapy, whereas NAIVE-ARD patients require the second dose to ensure a moderate antibody production. Our findings raise the possibility of a single dose regimen in ARD patients previously exposed to SARS-CoV-2.[clinicaltrials.gov#NCT04754698] Funding: FAPESP/CNPq/B3-Bolsa de Valores-Brasil. Declaration of Interest: The authors declare no competing interests. Ethical Approval: The protocol was approved by the National and Institutional Ethical Committee (CAAE: 42566621.0.0000.0068)