Since the onset of the COVID-19 pandemic, the World Health Organization has recommended vaccination for people with multiple sclerosis (pwMS). However, vaccine-induced immune responses in pwMS receiving immunomodulatory therapies are currently poorly characterized. Herein, we evaluated humoral and T cell-mediated immune responses against BNT162b2 mRNA vaccine in pwMS treated with cladribine (n = 30), focusing on how the time interval between drug administration and vaccination affects the magnitude and dynamics of vaccine-induced immune response. We found that cladribine influenced both B and T cell frequencies with different kinetics over time. Accordingly, vaccination after cladribine administration resulted in reduced antibody production but preserved T cell responses, whereas pwMS receiving vaccine before cladribine exhibited an effective humoral immunity but hampered SARS-CoV-2 Spike-specific T cell response. Our findings may inform the clinical decision-making process by providing evidence to support the identification of an appropriate time window for vaccination during cladribine treatment.
Effect of dynamics and timing of SARS-CoV-2 vaccination on immune response in people with multiple sclerosis during cladribine treatment / Russo, C., Fusco, C., Carbone, F., Micillo, T., La Rocca, C., De Rosa, G., Di Marino, V., Ruggiero, K., Garziano, F., Perna, F., Zannella, C., Galdiero, M., Franci, G., Lanzillo, R., Brescia Morra, V., Bigi, R., Abbadessa, G., Bonavita, S., Salvetti, M., Moccia, M., et al.. - In: CLINICAL IMMUNOLOGY. - ISSN 1521-7035. - 284:(2026). [10.1016/j.clim.2026.110683]
Effect of dynamics and timing of SARS-CoV-2 vaccination on immune response in people with multiple sclerosis during cladribine treatment
Bigi R.;Salvetti M.;Matarese G.
2026
Abstract
Since the onset of the COVID-19 pandemic, the World Health Organization has recommended vaccination for people with multiple sclerosis (pwMS). However, vaccine-induced immune responses in pwMS receiving immunomodulatory therapies are currently poorly characterized. Herein, we evaluated humoral and T cell-mediated immune responses against BNT162b2 mRNA vaccine in pwMS treated with cladribine (n = 30), focusing on how the time interval between drug administration and vaccination affects the magnitude and dynamics of vaccine-induced immune response. We found that cladribine influenced both B and T cell frequencies with different kinetics over time. Accordingly, vaccination after cladribine administration resulted in reduced antibody production but preserved T cell responses, whereas pwMS receiving vaccine before cladribine exhibited an effective humoral immunity but hampered SARS-CoV-2 Spike-specific T cell response. Our findings may inform the clinical decision-making process by providing evidence to support the identification of an appropriate time window for vaccination during cladribine treatment.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
