Fig 4. Effect of the pH-dependent C5-binding property and surface-charge engineering on endogenous C5 accumulation and antibody PK in cynomolgus monkeys.

Anti-C5 antibodies were intravenously administered to cynomolgus monkeys, and the changes in plasma C5 concentration (A, C) and plasma antibody concentration (B, D) were measured. pH-dependent antibodies with improved FcRn-binding activity, 305LO1-SG407, 305LO1-SG419, 305LO5-SG115, and 305LO8-SG115, were injected at day 0 (20 mg/kg). A pH-dependent C5-binding antibody with no FcRn-binding activity, 305LO1-SG406, was injected at days 0, 3, 6, and 9 (40 mg/kg). A non-pH-dependent C5-binding antibody, CFA0322-IgG₄, was injected at day 0 and 14 (40 mg/kg). Data are presented as mean ± S.D. n = 4. Data points affected by cynomolgus antibodies against the test samples were not included when calculating the mean concentrations.