Serum concentration profiles of ATLG IV applied from day –12 to day –9 before haplo-HSCT. Day 0 is defined as the day of transplant. (A) Mean serum concentrations of T-cell–specific rabbit ATLG over time according to dosing (circle, 15 mg/kg; triangle, 30 mg/kg; square, 60 mg/kg). (B) Mean serum concentration curves of T-cell–specific rabbit ATLG over time, shown on semilogarithmic scale. ATLG concentrations declined according to a monoexponential log-linear function. (C-E) ATLG serum concentrations, shown as spaghetti plots, in 18 patients after IV administration of (C) 15 mg/kg (n = 5), (D) 30 mg/kg (n = 9), or (E) 60 mg/kg (n = 4) ATLG.