Female EAE mice received individualized daily oral treatment of vehicle (EAE-Veh) or evobrutinib (EAE-Evo) for 4 days from the day of disease onset. EAE was scored clinically each day and flow cytometry analyses of spleens and spinal cords were performed. EAE-Evo mice with a clinical course indistinguishable from that of EAE-Veh were classified as non-responders (Evo-NR), whereas those with less severe disease were considered responders (Evo-R).

The therapeutic response in Evo-R was associated with an increase in MHC-II⁺ cDC (mature cDCs) in the spleen. Evobrutinib shifted the correlation between CD69⁺ T cells/cDCs from positive to inverse. However, Evo-NR mice showed myeloid content similar to EAE-Veh mice and Evo-R mice exhibited a lower myeloid cell infiltrate in the spinal cord, albeit enriched in mature cDCs. Evobrutinib induced specific modifications in the immunological synapse components in cDCs. Whereas both Evo-R and Evo-NR showed a decrease in MHC-II in splenic cDCs, only Evo-R exhibited a decrease in CD80. In contrast, spinal cord cDCs showed decreased CD80 with no modification of MHC-II brightness.