Successful peripheral blood stem cell mobilization with a cost-efficient single fixed-dose plerixafor schedule in poor mobilizers.

Plerixafor, although costly, is added to mobilizing chemotherapy and G-CSF to overcome poor stem cell mobilization. We demonstrate that it can be safely administered mostly once as a single dose in preemptive and rescue settings, leading to apheresis yields of >2 and >4×10 CD34 + cells/kg body weight (bw) in 83% and 48%, respectively. Of note, 35/46 (76%) patients showed a substantial benefit with increased peripheral blood (PB) CD34 + cells prior to apheresis (8.84 vs. 1.72/μl, p < .001), and 5-fold increased CD34 + cells collected per single apheresis (2.25 vs. 0.43 × 10 CD34+/kg bw, respectively, p < .001). Patients profiting most (76%) vs. less (24%) had >5 vs. <5/μl PB CD34 + cells before plerixafor application, respectively, thus careful patient selection in the latter group is advised. To the best of our knowledge, this is the first report demonstrating that favorable apheresis results can be obtained using this cost-efficient, single fixed-dose plerixafor schedule.