A phase 2 pilot study of pegfilgrastim and filgrastim for mobilizing peripheral blood progenitor cells in patients with non-Hodgkin’s lymphoma receiving chemotherapy

Abstract

Background Growth factors are frequently used to aid peripheral blood progenitor cell mobilization from bone marrow. This phase 2 study examined the efficacy and safety of pegfilgrastim for mobilizing peripheral blood progenitors cells for autologous transplantation.Design and Methods Patients with non-Hodgkin’s lymphoma received one cycle of mobilizing chemotherapy (ifosfamide, carboplatin and etoposide, ICE). Twenty-four hours later they were randomized, double-blind, to receive a single dose of pegfilgrastim 6 mg or 12 mg, or filgrastim 5 μg/kg/day (until the end of leukapheresis). Following leukapheresis (collection phase), patients rested or received one or two ‘salvage’ cycles of ICE. High-dose BEAM chemotherapy was then given before peripheral blood progenitor cell transplantation. The primary end-point was the patients’ mean yield of CD34+ cells/kg during the collection phase.Results Ninety patients were randomized and received a study drug; 63% completed the collection phase. The patients’ mean (95% CI) CD34+ cell harvest per leukapheresis was 0.8 (0.5–1.4), 0.8 (0.5–1.6) and 1.2 (0.7–2.0)×106 cells/kg for the pegfilgrastim 6 mg, pegfilgrastim 12 mg and filgrastim groups, respectively. Twenty (69%), 17 (59%) and 23 (72%) patients in these three groups achieved the targeted minimum harvest (≥2×106 cells/kg). The mean total harvests were 1.7, 1.4 and 2.2×106 cells/kg, respectively. Post-transplantation, the median days to absolute neutrophil count recovery (≥0.5×109/L) were 12, 11, and 11, respectively. Pegfilgrastim and filgrastim were generally well tolerated.Conclusions Pegfilgrastim (6 or 12 mg) was effective for mobilizing peripheral blood progenitors cells in patients with non-Hodgkin’s lymphoma. These data may aid the design of studies to clarify optimal dosing and leukapheresis with pegfilgrastim.