An Exploratory Safety Study to Investigate the Extent of Tumor Cell Mobilization (TCM) After Use of G-CSF Alone or G-CSF Plus Plerixafor in Multiple Myeloma (MM) Patients Who May be Poor Mobilizers of Stem Cells

The primary objective of this study is to evaluate tumor cell mobilization (TCM) with non-pegylated G-CSF alone compared with non-pegylated G-CSF plus plerixafor in patients with multiple myeloma (MM) who are potentially poor mobilizers of hematopoietic stem cells (HSC). Second objectives are to evaluate survival and disease status of G-CSF alone compared with GCSF plus plerixafor, and the efficacy and safety of G-CSF plus plerixafor when used to mobilize stem cells for autologous transplantation.