Antibody and T-cell responses to SARS-CoV-2 vaccines in MS patients on Ocrelizumab and other disease-modifying therapies: Preliminary results of an ongoing, prospective study

Objective: To compare humoral and T-cell responses to COVID- 19 vaccines in 400 MS patients who were on Ocrelizumab ('OCR') v. other disease-modifying therapies ('non-OCR') at the time of vaccination. Introduction: Peripheral B-cell depletion with anti-CD20 therapies attenuates humoral responses to vaccines. Whether immune responses to COVID-19 vaccines differ between B-cell depleted and non-B cell depleted MS patients is not known. Methods: Consecutive MS patients from NYU MS Care Center were invited to participate if they completed COVID-19 vaccination ≥6 weeks previously. Immune testing included anti-spike RBD antibody (Elecsys Anti-SARS-CoV-2) (Roche Diagnostics);multiplex bead-based immunoassays of antibody-responses to SARS-COV-2 spike proteins;T-cell responses to SARS-CoV-2 Spike protein using IFNγ enzyme-linked immune-absorbent spot (Invitrogen) and TruCulture (Myriad RBM) assays;high dimensional immunophenotyping;and live virus immunofluorescencebased microneutralization assay. Results: As of 7/15/2021, 105 MS subjects were enrolled (mean age: 40.5 years;76% female;41% non-white;38% on OCR;12% with prior COVID-19 infection). 95% were fully vaccinated with mRNA vaccines (Pfizer/Moderna);5% - with adenovirus-based vaccine (JohnsonJp<0.0001). Positive response by multiplex assay (threshold of 'positive' defined as 2 SD below the mean for the non-OCR) were detected in 10/27 (37%) OCR and 29/31 (94%) non-OCR (p<0.00001). T-cell activation based on induced IFNγ secretion (TruCulture) was detected in 20/25 (80%) OCR and 16/19 (84%) non-OCR patients (p=0.71). Conclusions: Preliminary results suggest robust T-cell immune response to SARS-CoV2 vaccines in approximately 80% of both OCR and non-OCR MS patients. Antibody responses were markedly attenuated in OCR compared to non-OCR group. Updated results will be presented.