Long-acting granulocyte colony-stimulating factor pegfilgrastim (lipegfilgrastim) for stem cell mobilization in multiple myeloma patients undergoing autologous stem cell transplantation.

Autologous stem cell transplantation (ASCT) is a standard of care in newly-diagnosed multiple myeloma (MM) patients. Several studies before the introduction of novel therapies in MM, demonstrated a pegylated G-CSF to be successful in mobilizing peripheral blood stem cells (PBSCs). Lipegfilgrastim is a novel long-acting G-CSF that is produced by the conjugation of a single 20-kDa polyethelene glycol to the natural O-glycosylation site of G-CSF. Twenty-four MM patients were included for PBSCs mobilization with a single SC injection of 6 mg lipegfilgrastim. PBSC collection was started when the CD34+ count was > 10 × 106 cells/L. The target progenitor cells were 6 × 106 cells/kg. The median day of apheresis was + 3 (range 2-5) following lipegfilgrastim. Median peripheral blood CD34+ count pre-mobilization was of 22.65 (range 3.36-105) × 106 cells/L. The median number of leukaphaeresis procedures was 2 (range 1-4). The median mobilized CD34+ cells/kg were 8.26 (range 0.77-12.42). One patient failed to mobilize and two patients mobilized < 6 × 106 cells/kg. Toxicity was mild and transient. Twenty-three patients underwent ASCT following high dose melphalan. All patients engrafted. As lipegfilgrastim is administered only once, it is conceivable that it improves both compliance and quality-of-life (NCT02488382).