In-depth characterization of long-term humoral and cellular immune responses to COVID-19m-RNA vaccination in multiple sclerosis patients treated with teriflunomide or alemtuzumab.

BACKGROUND: The impact of disease-modifying therapies on the efficacy to mount appropriate immune responses to COVID-19 vaccination in patients with multiple sclerosis (MS) is currently under investigation. OBJECTIVE: To characterize long-term humoral and cellular immunity in mRNA-COVID-19 MS vaccinees treated with teriflunomide or alemtuzumab. METHODS: We prospectively measured SARS-COV-2 IgG, memory B-cells specific for SARS-CoV-2 RBD, and memory T-cells secreting IFN-γ and/or IL-2, in MS patients vaccinated with BNT162b2-COVID-19 vaccine before, 1, 3 and 6 months after the second vaccine dose, and 3-6 months following vaccine booster. RESULTS: Patients were either untreated (N = 31, 21 females), under treatment with teriflunomide (N = 30, 23 females, median treatment duration 3.7 years, range 1.5-7.0 years), or under treatment with alemtuzumab (N = 12, 9 females, median time from last dosing 15.9 months, range 1.8-28.7 months). None of the patients had clinical SARS-CoV-2 or immune evidence for prior infection. Spike IgG titers were similar between untreated, teriflunomide and alemtuzumab treated MS patients both at 1 month (median 1320.7, 25-75 IQR 850.9-3152.8 vs. median 901.7, 25-75 IQR 618.5-1495.8, vs. median 1291.9, 25-75 IQR 590.8-2950.9, BAU/ml, respectively), at 3 months (median 1388.8, 25-75 1064.6-2347.6 vs. median 1164.3 25-75 IQR 726.4-1399.6, vs. median 837.2, 25-75 IQR 739.4-1868.5 BAU/ml, respectively), and at 6 months (median 437.0, 25-75 206.1-1161.3 vs. median 494.3, 25-75 IQR 214.6-716.5, vs. median 176.3, 25-75 IQR 72.3-328.8 BAU/ml, respectively) after the second vaccine dose. Specific SARS-CoV-2 memory B cells were detected in 41.9%, 40.0% and 41.7% of subjects at 1 month, in 32.3%, 43.3% and 25% at 3 months, and in 32.3%, 40.0%, 33.3% at 6 months following vaccination in untreated, teriflunomide treated and alemtuzumab treated MS patients, respectively. Specific SARS-CoV-2 memory T cells were found in 48.4%, 46.7% and 41.7 at 1 month, in 41.9%, 56.7% and 41.7% at 3 months, and in 38.7%, 50.0%, and 41.7% at 6 months, of untreated, teriflunomide-treated and alemtuzumab -treated MS patients, respectively. Administration of a third vaccine booster significantly increased both humoral and cellular responses in all patients. CONCLUSIONS: MS patients treated with teriflunomide or alemtuzumab achieved effective humoral and cellular immune responses up to 6 months following second COVID-19 vaccination. Immune responses were reinforced following the third vaccine booster.

Cladribine treatment for highly active multiple sclerosis: Real-world clinical outcomes for years 3 and 4.

INTRODUCTION: Cladribine is an effective immunomodulatory treatment used for relapsing forms of multiple sclerosis (MS). OBJECTIVES: To describe the clinical outcomes and rates of no evidence of disease activity (NEDA) in patients with highly-active disease treated with 2 years cumulative dose of cladribine, for years 3 and 4. METHODS: We used the Sheba Multiple Sclerosis computerized data registry to retrospectively evaluate year-3 and year-4 clinical outcomes and NEDA-2 rates in highly active RRMS patients who completed the 2-dose 2-year cladribine treatment protocol (3.5 mg/kg cumulative dose over 2 years). The first week of treatment in year 1 was considered as baseline. Data analyses were performed using Python (version 3.0) and SAS® (version 9.4 SAS Institute, Cary, NC). RESULTS: Among 128 patients with highly-active MS that received cladribine treatment, 61 patients, 43 females, were studied for year-3 clinical outcomes, and 35 patients, 23 females, also for year-4. At the initiation of cladribine treatment, the mean ± SD age was 39.6 ± 10.74 years (45.9% of the patients were between 18 and 40 years), disease duration 12.7 ± 9.08 years, Expanded Disability Status Scale (EDSS) 3.7 ± 1.86 (54% had EDSS score > 3.0), and the annual relapse rate was 1.6 ± 0.9. The annual relapse rate decreased to 0.36 in year-3 and was 0.17 in year-4; 68.9% (42/61) of the patients were relapse-free in year-3, and 82.9% (29/35) were relapse-free in year-4. Disability at year-3 was 3.1 ± 2.07; 83.6% (51/61) of the patients remained neurologically stable (33, 54.1%) or improved (18, 29.5%). In year-4, EDSS was 3.2 ± 1.91, and 85.7% (30/35) of the patients remained stable (20, 57.1%) or improved (10, 28.6%). NEDA-2 was achieved for 59.0% (36/61) of patients in year-3, and for 74.3% (26/35) in year-4 of cladribine treatment. CONCLUSIONS: In the real-world cladribine proved to be clinically effective in year-3 and year-4 of treatment in the majority of highly active RRMS patients.