Table 2.

Results of pharmacokinetic analysis after the first dose of IL-21

Dose level (μg/kg)
AUC0-inf C (ng·h/mL; AUC%extrap)2.9 (26.1)19.9 (10.8)66.0 (1.8)193 (0.9)336 (1.2)476 (1.4)
C5min (ng/mL)1.89.732.8107194270
t1/2 (h)
CL (mL/kg/h)339151152155149210
Vss (mL/kg)523262344437533949
Vz (mL/kg)5292773766667131287
  • NOTE: Geometric means: AUC0-inf = AUC until infinity; AUC%extrap = area extrapolated after last quantifiable concentration; C5min = IL-21 concentration 5 min after injection; t1/2 = terminal half-life; CL = total clearance of IL-21 from plasma; Vss = apparent volume of distribution at equilibrium; Vz = apparent volume of distribution during the terminal phase.