Based on a population pharmacokinetic analysis in 298 NHL patients who received single or multiple infusions of rituximab as a single agent or in combination with CHOP therapy (applied rituximab doses ranged from 100 to 500 mg/ m2), the typical population estimates of nonspecific clearance (CL1), specific clearance (CL2) likely contributed by B cells or tumor burden, and central compartment volume of distribution (V1) were 0.14 L/ day, 0.59 L/ day, and 2.7 L, respectively.