Antibody response of Comirnaty vaccine in different immunocompromised groups during the COVID-19 pandemic

Abstract

Abstract A nationwide vaccination program was initiated on February 23, 2021, in Mongolia by 4 types of vaccines for COVID-19 were offered voluntarily. People at increased risk of severe disease were vaccinated with Comirnaty. In this study, we aimed to compare specific antibody responses after the second dose of the Comirnaty vaccine in different immunocompromised groups. This prospective cohort study was conducted from March–April to July–August of 2021. 225 vaccinees presented an immunocompromised population examined for anti-SARS-CoV-2 RBD-IgG (ELISA, Proteintech, USA) before the first dose of vaccine and RBD-IgG antibodies were measured 14 – 21 days after the second dose of vaccine. An increase of antibody titer more than 3-fold was considered a positive antibody response after vaccination. We could attend to the after the second dose of examination 172 (76.4%) of 225 vaccinees. Antibody response to COVID-19 vaccines was detected in 164 (95.1%) vaccinees that demonstrated positive antibody response. A positive response was found in all (100.0%) immunocompromised (19 patients received anti-cancer chemotherapy, 90 patients received corticosteroids, 63 HIV-infected patients) groups. The mean titer of RBD-IgG antibodies in anti-cancer chemotherapy (185.1±49.1ng/mL, CI95: 161.4–208.8) and corticosteroids group (161.6±70.3 ng/mL, CI95: 147.1–176.2) was significantly higher compared to HIV-infected group (98.8±32.6 ng/mL, CI95: 90.6–107.0). A significant impact on antibody response after the second dose of Comirnaty COVID-19 vaccination was associated with the immunocompromised condition. The study was funded by the Ministry of Health of Mongolia. None