[Mobilization of peripheral blood stem cells with plerixafor in poor mobilizer patients]

Poor mobilization of peripheral blood stem cells (CD34(+) cells) from bone marrow is a frequent reason for not reaching the autologous stem cell trasplantation (SCT) procedure in patients diagnosed with lymphoma or myeloma. Plerixafor, a reversible inhibitor of the binding of stromal cell-derived factor 1 to its cognate receptor CXCR4, has demonstrated a higher capacity for the mobilization of peripheral blood stem cells in combination with granulocyte colony stimulating factor (G-CSF) compared with G-CSF alone. For this reason, plerixafor is now indicated for poor mobilizer myeloma or lymphoma patients. Some studies have recently indicated that a pre-emptive strategy of plerixafor use during first mobilization, according to the number of CD34(+) mobilized cells in peripheral blood or to the harvested CD34(+) cells after first apheresis, could avoid mobilization failures and re-mobilizations, as well as the delay of autologous SCT. The aim of this consensus was to perform a review of published studies on pre-emptive strategy and to establish common recommendations for hospitals in Catalonia and Balearics on the use of pre-emptive plerixafor.

For the Consensus, physicians from participant hospitals met to review previous studies as well as previous own data about plerixafor use. The GRADE system was used to qualify the available evidence and to establish recommendations on the use of pre-emptive plerixafor.

After a review of the literature, the expert consensus recommended the administration of pre-emptive plerixafor for multiple myeloma or lymphoma patients with a CD34+ cell count lower than 10 cells/μL in peripheral blood (measured in the morning of day 4 of mobilization with G-CSF or after haematopietic recovery in the case of mobilization with chemotherapy plus G-CSF).