Fixed-dose single agent pegfilgrastim for peripheral blood progenitor cell mobilisation in patients with multiple myeloma

High-dose chemotherapy and autologous peripheral blood progenitor cell transplantation is an effective treatment for multiple myeloma. Progenitor cells are generally mobilised into the peripheral blood by administration of filgrastim. Pegfilgrastim is a covalent conjugate of filgrastim with a longer half-life. The results of a phase II study of pegfilgrastim, administered as a single injection to mobilise autologous peripheral blood progenitor cells in patients with multiple myeloma, is reported. All patients (n = 19) received 12 mg of pegfilgrastim. Leukaphaeresis was started when the peripheral blood CD34(+) count was > 0.015 x 10(9)/l. Daily, leukaphaeresis was performed until the target progenitor cell dose was obtained. The median number of leukaphaeresis procedures required to collect the target CD34(+) cell dose was 2 (range 1-5). A median of 8.4 x 10(6) CD34(+) cells/kg (range 4.1-15.8) was collected. The most common toxicity was bone pain/myalgia. Sustained haematological recovery occurred in all the patients who underwent high-dose chemotherapy followed by autologous peripheral blood progenitor cell transplantation with pegfilgrastim-mobilised cells. A single fixed dose of pegfilgrastim was effective in mobilising adequate peripheral blood progenitor cells in patients with multiple myeloma. The efficacy and toxicity profile was similar to that described with filgrastim treatment.