Abstract
Background COVID-19 vaccination induces protective spike antibodies. Some responses are attenuated in people living with multiple sclerosis (MS) on high efficacy disease modifying therapies (DMT). It is unknown whether antibodies afford immunity against emerging SARS-CoV-2 variants such as Delta and Omicron.
Objective We aimed to determine the longevity and breadth of spike antibody in MS patients after COVID-19 vaccination.
Methods Spike antibodies to Wuhan SARS-CoV-2 were assessed in 454 sera of MS patients at baseline (n=303), 1 month post-second dose (n=121), 6 months post-second dose (n=19) and 1 month post-third dose (n=11). Spike antibody binding to Delta and Omicron was assessed in 83 sera 1 month post-second dose. Demographic and clinical information were available in 146 patients.
Results 104/121 sera at 1 month post-second dose, 16/19 sera at 6 months post-second dose, and 10/11 sera at 1 month post-third dose were positive for Spike antibodies. Treatment information was available in 9/17 patients who did not seroconvert at 1 month post-second dose. N=7 were treated with Ocrelizumab and n=2 by Cladribine. 87/104 who seroconverted had titers comparable to the general population, and 17 had reduced titres. Treatment information was available in 14/17 of these patients, 6/14 were on Ocrelizumab, 5/14 were on Fingolimod, 2/14 were on Ofatumumab, and 1/14 was on Siponimod. Spike antibody immunoreactivity was markedly decreased to Delta and Omicron.
Conclusion Some DMTs reduce Spike antibody titres or prevent seroconversion. The Sequence of spike used in the first generation of vaccine may need to be updated for emerging variants.
