LAUSR

Pegylated recombinant human granulocyte colony‐stimulating factor (PEG‐rhG‐CSF, pegfilgrastim) is a long‐acting derivative of recombinant human granulocyte colony‐stimulating factor with limited renal clearance and a longer half‐life. It is used for the prevention of febrile neutropenia, owing to its capacity to promote neutrophil recovery. In this study, the pharmacokinetics, pharmacodynamics, safety, and immunogenicity of 2 formulations of PEG‐rhG‐CSF were evaluated in healthy Chinese subjects. Twenty‐four male subjects who received a single dose of subcutaneous PEG‐rhG‐CSF 100 µg/kg were randomized to either treatment A (3 mg/mL) or treatment B (1 mg/mL). Noncompartmental pharmacokinetic parameters of PEG‐rhG‐CSF were derived from serum concentration‐time data. In addition, absolute neutrophil count (ANC) as a pharmacodynamic maker, immunogenicity through antidrug antibody testing, and safety were evaluated. The mean area under the concentration‐time curve from time zero to the last quantifiable concentration (AUC0‐t) and the mean maximum concentration (Cmax) of PEG‐rhG‐CSF after treatment A were 5070 ng·h/mL and 125 ng/mL, respectively; these values were comparable to those measured after treatment B (5340 ng·h/mL and 123 ng/mL, respectively). The mean value of area under the △ANC (baseline‐adjusted ANC)‐time curve and the maximum △ANC values were 4380 × 109 h/L and 33.1 × 109/L, respectively, in the treatment A group, and 5170 × 109 h/L and 38.6 × 109/L, respectively, in the treatment B group. The pharmacokinetic and pharmacodynamic profiles were similar for the 2 PEG‐rhG‐CSF formulations following a single dose of 100 µg/kg. The safety and immunogenicity profiles were also similar, with no significant differences. The dose adjustment of PEG‐rhG‐CSF was not considered necessary for formulation transformation.