Reozalimab(Ibi318) is a first-in-class recombinant IgG1 bispecific antibody that targets both PD-1 and PD-L1, with checkpoint inhibitory, immunostimulating, and antineoplastic activities. It fully blocks the PD-1 pathway, disrupts PD-L1/CD80 interactions, and enhances T cell activation for improved tumor cell killing. M.W 143.84 kDa