Herein, we generated and evaluated a series of CD3 bsAbs with altered binding affinity to CD3 that maintained unaltered binding to the tumor-cell-specific antigens (TSAs) across several distinct tumor targets (prostate specific membrane antigen [PSMA], Mucin-16 for ovarian cancer [MUC16], B-cell maturation antigen [BCMA], CD20). The gene discussed is FOLH1; the disease is ovarian cancer.