A Randomized Phase II Trial Comparing Stem Cell Mobilization With Chemotherapy and Cytokine (G-CSF) Versus Cytokine (G-CSF) Alone in Myeloma Patients (MOCCCA-trial).

Background and Rationale High-dose chemotherapy (HDCT) with melphalan and autologous stem cell transplantation (ASCT) remains an integral component of the myeloma treatment algorithm for patients considered eligible for the procedure, nowadays performed in myeloma patients up to the age of 75 years. Until the advent of the novel agents, the initial therapy regimens commonly used were vincristine, doxorubicin, and dexamethasone (VAD) or single-agent dexamethasone, both of which shared the advantage of having little impact on stem cell mobilization and collection. Previous studies had shown that alkylating agents can potentially affect the stem cell pool and thus interfere with the ability to collect adequate numbers of stem cells. However, VAD is no longer uses nowadays, whereas current lenalidomide-containing combinations significantly affect stem cell collection. .In Switzerland, the combination of non-myeloablative chemotherapy with vinorelbine or gemcitabine and G-CSF is the current standard procedure. With the predominant use of bortezomib during induction treatment more patients have pre-existing neurotoxicity. Vinorelbine can aggravate this problem. Recently data have shown that a mobilization with gemcitabine together with G-CSF is safe and effective in myeloma patients. Whether chemotherapy is mandatory at all to achieve the same reliable and cost-effective mobilization is currently unknown. The investigators therefore consider that a direct comparison between vinorelbine/gemcitabine and G-CSF versus G-CSF alone is justified.