Inactivated SARS-CoV-2 vaccine does not increase the risk of relapse in patients with clinically inactive adult-onset Still's disease.

OBJECTIVE: A succession of cases have reported flares of adult-onset Still's disease (AOSD) after vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), raising concerns. We aimed to investigate the impact of inactivated SARS-CoV-2 vaccines on disease activity in patients with AOSD. METHODS: We prospectively enrolled clinically inactive AOSD patients visiting the outpatient clinics of our department. The patients received SARS-CoV-2 vaccines (BBIBP-CorV, Sinopharm, Beijing, China) voluntarily. The occurrence of relapse in the participants was recorded during the follow-up period, and a propensity score matching (PSM) method was used to compare the relapse rates between vaccinated and unvaccinated patients. Localized and systemic symptoms were assessed in the vaccinated patients. RESULTS: A total of 122 patients with inactive AOSD were included, of which 49.2% (n = 60) voluntarily received the inactivated SARS-CoV-2 vaccine. The relapse rate did not increase significantly in vaccinated patients in comparison with unvaccinated patients (after PSM: 6.8% vs 6.8%), and no relapse occurred within 1 month after vaccination. No obvious adverse reactions were reported in 75.0% of the participants, and none of the patients reported severe reactions. CONCLUSION: Increased disease activity or relapse following vaccination with inactivated SARS-CoV-2 was rare in patients with inactive AOSD. Local and systemic adverse reactions were found to be mild and self-limiting. These safety profiles of inactivated SARS-CoV-2 vaccines in patients with AOSD may assist in eliminating vaccine hesitancy and increase the vaccination rate against SARS-CoV-2.