eng Drulović, Jelena Pekmezović, Tatjana Mesaroš, Šarlota Gnjatović, Marija Ćujić, Danica Veselinović, Nikola Tamas, Olivera Martinović, Vanja Ivanović, Jovana info:eu-repo/semantics/article https://phaidrabg.bg.ac.rs/o:26024 doi:10.1016/j.msard.2021.103150 ABSTRACT Background: It has been generally accepted that people with MS (PwMS) should be vaccinated against COVID-19. The aim of our investigation was to evaluate the humoral response to natural SARS-CoV-2 infection and to two COVID-19 vaccines (BNT162b2 Pfizer-BioNTech and Beijing/Sinopharm BBIBP-CorV) in our cohort of PwMS under high efficacy disease modifying therapies (DMTs), cladribine and alemtuzumab. Methods: Twenty two PwMS treated at the Clinic of Neurology, in Belgrade, who developed COVID-19 and/or were vaccinated against SARS-CoV-2, during treatment with cladribine and alemtuzumab, were included. Out of 18 patients treated with cladribine, 11 developed COVID-19, and 11 were vaccinated against SARS-CoV-2 (four with mRNA vaccine, 7 with Sinopharm). Four MS patients under alemtuzumab were vaccinated against SARS-CoV-2; three with mRNA, and one with Sinopharm vaccine. SARS-Cov-2 IgG response was measured using ELISA anti- spike protein-based serology (INEP, Belgrade, Serbia). Results: All 7 patients under cladribine treatment who suffered from COVID-19, developed IgG antibodies, 2.0-5.5 months after last symptoms. All four (100%) patients under cladribine who were vaccinated with Pfizer-BioNTech vaccine, and three out of seven (42.9%) vaccinated with Sinopharm, developed antibodies. All 4 patients under alemtuzumab developed antibodies after vaccination. In all cases, seroprotection occurred, irrespective of timing of vaccination and absolute lymphocyte count. Conclusion: Our findings in a small number of highly active PwMS in whom, lymphodepleting, immune reconstitution therapies, were applied in order to successfully manage MS, indicate that in a number of these patients it was possible to develop at the same time seroprotection in these patients after COVID-19 vaccination in these complex circumstances. http://creativecommons.org/licenses/by-nc-nd/4.0/legalcode Humoral response to SARS-CoV-2 COVID-19 vaccines in patients with multiple sclerosis treated with immune reconstitution therapies application/pdf 656697 bytes Elsevier 2021 Multiple Sclerosis and Related Disorders 54 COVID-19, Pfizer-BioNTech, Sinopharm, alemtuzumab, cladribine, humoral response, multiple sclerosis, vaccination