Pharmacokinetic studies of alemtuzumab. (A) Semilogarithmic plots show alemtuzumab concentrations against time from transplantation according to each dose cohort. (B) Box-and-whisker histograms (showing median, range, and 25th and 75th percentiles) of alemtuzumab concentrations at day 0 and at day 28 after transplantation. Note linear y-axis. Dotted line represents limits of detection (37.5 ng/mL) for enzyme-linked immunoabsorbent assay. (C-E) Box-and-whisker histograms show clearance (Cl), central volume of distribution (V₁), and peripheral volume of distribution (V₂) according to a linear, 2 compartment model of elimination. (B-E) P values are shown for the 20-mg versus other groups as determined by 1-way analysis of variance.