Comparison of SARS-CoV-2 antibody response after two doses of mRNA and inactivated vaccines in multiple sclerosis patients treated with disease-modifying therapies

Background: Disease-modifying therapy could weaken the immune system and decrease the immune response to vaccines. It is essential to know which vaccine is more protective against SARS-CoV-2 in the multiple sclerosis population. Objective: To assess immune response after messenger RNA BNT162b2 (Pfizer/BioNTech) and inactivated Sinovac vaccines in people with multiple sclerosis (pwMS) treated with a disease-modifying therapy (DMT) compared to healthy controls. Methods: This single-center cross-sectional study included 526 MS patients treated with DMT, 44 healthy controls, and 21 untreated patients with MS between May 2021 and September 2021. Serum samples were collected at least two weeks after the second dose of the vaccine. Results: Participants vaccinated with BNT162b2 had a higher antibody titer than the Sinovac group (95%CI=1.023 – 1.473; p <.001). No significant difference between antibody titer of pwMS without treatment and HC was found [95%CI= -0.882; - 0.935 p >.99]. In 65 adults without DMT use (HC+pwMSwithout treatment), no seronegative cases were observed in any vaccine group. In patients treated with DMT, BNT162b2 was associated with a 16.3% greater absolute risk of seropositivity than Sinovac. Conclusion: The mRNA vaccine could be a preferred choice of protection against SARS-CoV-2 in pMS treated with DMT.