Ocrelizumab depletes T-lymphocytes more than rituximab in multiple sclerosis

• DOI: 10.1016/j.msard.2021.102802
• Publication Date: 2021-01-28T18:41:23Z
• Authors: Nicola Capasso; Agostino Nozzolillo; Giulia Scalia; Roberta Lanzillo; Antonio Carotenuto; Marcello De Angelis; Martina Petruzzo; Francesco Saccà; Cinzia Valeria Russo; Vincenzo Brescia ...; Marcello Moccia
• Keywords: Multiple Sclerosis; Lymphocytes; Multiple sclerosis; Ocrelizumab; Rituximab; Antibodies, Monoclonal, Humanized; Humans; Lymphocyte Count; Retrospective Studies; Rituximab; Multiple Sclerosis; Antibodies, Monoclonal, Humanized; Antibodies; 3. Good health; Multiple sclerosis; 03 medical and health sciences; 0302 clinical medicine; Monoclonal; Humans; Lymphocytes; Ocrelizumab; Lymphocyte Count; Rituximab; Humanized; Retrospective Studies

We aim to directly compare changes in lymphocyte subpopulations between chimeric (rituximab) and humanised (ocrelizumab) anti-CD20 antibodies in multiple sclerosis (MS).In this retrospective analysis of prospectively collected data, we included 88 patients with MS, treated with rituximab (n=50) or ocrelizumab (n=38). We used flow cytometry in the peripheral blood to count total lymphocytes and lymphocytes expressing different phenotypic markers (CD4, CD8, CD19, CD20, CD4/CD8 ratio), before treatment and after 1, 3 and 6 months.On linear mixed effect regression models, after 1, 3 and 6 months, patients treated with rituximab and with ocrelizumab were similar in total lymphocyte count, CD19 lymphocytes, CD20 lymphocytes and CD4/CD8 ratio. However, patients treated with ocrelizumab presented with lower CD4 T lymphocytes and CD8 T lymphocytes after 1, 3 and 6 months (all p<0.05). No between-treatment difference in EDSS progression was found.B-cell levels in the peripheral blood were equally decreased by rituximab and ocrelizumab. On the contrary, CD4 and CD8 T lymphocyte reduction was more pronounced in ocrelizumab, when compared with rituximab, suggesting a broader immunomodulatory effect for the humanised antibody to be confirmed and correlated with clinical efficacy in the long term.