Pegfilgrastim for peripheral CD34+ mobilization in patients with solid tumours

Area of Science:

• Oncology
• Hematology
• Pharmacology

Background:

• Stem cell mobilization is crucial for autologous transplantation in cancer patients.
• Filgrastim (granulocyte colony-stimulating factor) is commonly used but requires daily administration.
• Pegfilgrastim, a long-acting G-CSF, offers a potential alternative for simplified dosing.

Purpose of the Study:

• To assess the efficacy of single-dose pegfilgrastim compared to daily filgrastim for peripheral stem cell mobilization in patients with solid tumors.
• To determine the optimal pegfilgrastim dose for stem cell mobilization.
• To evaluate stem cell mobilization during both cytokine-only cycles and chemotherapy cycles.

Main Methods:

• Randomized, open-label study of 61 patients with solid tumors.
• Patients received single doses of pegfilgrastim (6, 12, or 18 mg) or daily filgrastim (10 µg/kg) in cycle 0 (cytokine-only).
• In cycle 1, patients received chemotherapy (carboplatin/paclitaxel) followed by randomized pegfilgrastim or filgrastim based on cycle 0 randomization.

Main Results:

• Pegfilgrastim demonstrated dose-dependent increases in peak CD34+ cell counts.
• The 18 mg pegfilgrastim dose showed significantly higher peak CD34+ counts than filgrastim in cycle 0 (10.17 vs 4.96 x 10^4/mL; P=0.014).
• Both 12 mg and 18 mg pegfilgrastim doses yielded significantly higher CD34+ counts during days 3-7 compared to filgrastim in cycle 0. In cycle 1, the 18 mg dose showed an advantage in the days 7-12 period (3.14 vs 1.19 x 10^4/mL; P=0.043).

Conclusions:

• A single dose of pegfilgrastim (≥6 mg) can effectively mobilize peripheral CD34+ cells, potentially replacing daily filgrastim.
• Higher doses of pegfilgrastim (12 and 18 mg) show superior efficacy during the early mobilization phase.
• Pegfilgrastim offers a convenient and effective option for stem cell mobilization in patients undergoing chemotherapy for solid tumors.