Longitudinal humoral response in MS patients treated with cladribine tablets after receiving the second and third doses of SARS-CoV-2 mRNA vaccine

Abstract

Background: Multiple sclerosis (MS) patients receive immunomodulatory treatments which can influence their ability to maintain vaccine specific serological response overtime. MS patients treated with cladribine tablets developed a positive serology response following two doses of mRNA COVID-19 vaccine. However, there is only limited data regarding the effect of cladribine tablets on long-term humoral response after the second and the third booster.

Methods: Serology response to SARS-CoV-2 was tested in healthy controls (HCs) and MS patients treated with cladribine tablets 6 and 9-12 months after the second dose, and 1 and 3-6 months following the third booster-dose of the BTN162b2 mRNA vaccine.

Results: Thirty-five out of 36 MS patients treated with cladribine tablets and 100% (46/46) of HCs had a positive serology response up to 10 months after the second vaccine dose. In addition, all cladribine tablets -treated MS patients (22/22) and HCs (24/24) had a positive robust serology response following the third vaccine with a positive humoral response sustain up to 6 months. One month after the third vaccine dose IgG levels were significantly lower in patients treated with cladribine tablets compared to HCs (15,598+11,313 vs 26,394+11,335, p<0.01). Six-month post second vaccine and 3-6 months post third vaccine there was no difference in IgG levels between the groups (1088.0 ± 1072.0 vs 1153.0 ± 997.1, p = 0.79; 5234+4097 vs 11,198+14,679, p = 0.4).

Conclusion and relevance: MS patients treated with cladribine tablets have sustained positive vaccine specific serology response following the second and third SARS-CoV-2 vaccine dose.

Keywords: COVID-19 vaccination; Cladribine tablets; Long term serology response; Multiple sclerosis.

Fig. 1

Longitudinal serology response to SARS-CoV-2 mRNA vaccine of cladribine treated MS patients and HCs.Fig. 1 Serology response of HCs and cladribine tablets-treated MS patients following the 2nd and 3rd mRNA vaccine dose on logarithmic amplitude scale. 2–3 weeks (n = 31, 13,003±8893AU/ml vs n = 21, 11,135±12,029, p = 0.52), and 6 months (n = 46, 1153.0 ± 997.1 vs n = 36, 1088.0 ± 1072.0, p = 0.79) following the 2nd vaccine, and 1 month (n = 24, 26,394±11,335 vs n = 17, 15,598±11,313, p = 0.40) and 3–6 months (n = 8, 11,198±14,679 vs n = 5, 5234±4097, p = 0.40) following the 3rd vaccine. Data presented as mean±SD. Dotted line indicates positive threshold (≥50 AU/ml).