In vivo efficacy of cAbs 65C6/IgG2a, 65C6/D265A, 100F4/IgG2a, and 100F4/D265A in minimum protective doses against the lethal challenge of virus strains SZ06, SX06, and NE14. (A to F) Time course of body weight changes (top panels) and survival rate of each group (bottom panels) against SZ06 (A and D), NE14 (B and E), and SX06 (C and F) by 100F4/IgG2a and 100F4/D265A cAbs (A to C) and by 65C6/IgG2a and 65C6/D265A cAbs (D to F) along with VRC01 control antibody. The survival rate was calculated as percent survival within each experimental group (five mice in each group).