mbs303MBS 303 is a bispecific antibody targeting CD3CD20 being developed by Beijing Mabworks Biotech for the treatment of B cell non-Hodgkin lymphoma. TheMBS303 is a CD20×CD3 T-cell-engaging bispecific antibody that has a novel 2:1 (CD20:CD3) confuration to kill malnant B cells. This dose-escalation phase Ⅰ trial