RESUMO
Historically, up to 30% of patients were unable to collect adequate numbers of peripheral blood stem cells (PBSCs) for autologous stem cell transplantation (ASCT). Plerixafor in combination with granulocyte colony-stimulating factor (G-CSF) has shown superior results in mobilizing peripheral blood (PB) CD34+ cells in comparison to G-CSF alone, but its high cost limits general use. We developed and evaluated risk-adapted algorithms for optimal utilization of plerixafor. In plerixafor-1, PBSC mobilization was commenced with G-CSF alone, and if PB CD34 on day 4 or day 5 was <10/µL, plerixafor was administered in the evening, and apheresis commenced the next day. In addition, if on any day, the daily yield was <0.5 × 10(6) CD34/kg, plerixafor was added. Subsequently, the algorithm was revised (plerixafor-2) with lower thresholds. If day-4 PB CD34 <10/µL for single or <20/µL for multiple transplantations, or day-1 yield was <1.5 × 10(6) CD34/kg, or any subsequent daily yield was <0.5 × 10(6) CD34/kg, plerixafor was added. Three time periods were analyzed for results and associated costs: January to December 2008 (baseline cohort; 319 mobilization attempts in 278 patients); February to November 2009 (plerixafor-1; 221 mobilization attempts in 216 patients); and December 2009 to June 2010 (plerixafor-2; 100 mobilization attempts in 98 patients). Plerixafor-2 shows a significant improvement in PB CD34 collection, increased number of patients reaching minimum and optimal goals, fewer days of apheresis, and fewer days of mobilization/collection, albeit at increased costs. In conclusion, although the earlier identification of ineffective PBSC mobilization and initiation of plerixafor (plerixafor-2) increases the per-patient costs of PBSC mobilization, failure rates, days of apheresis, and total days of mobilization/collection are lower.
