Harvesting of Peripheral Blood Stem Cells Using Plerixafor (MOZOBIL) and Granulocyte-Colony Stimulating Factor in Patients Who Had Never Undergone Stem Cell Collection.

The collection of peripheral blood stem cells (PBSC) can be tedious and expensive. Moreover, PBSC yields can be severely compromised in patients who previously received chemotherapy. The use of plerixafor (MOZOBIL) for PBSC mobilization has been shown to significantly improve CD34 stem cell yields in patients whom PBSC collections have been adequate. However, this requires the patient to undergo further PBSC harvesting sessions; adding to the patient's inconvenience, exposure to adverse events and costs. We therefore investigated whether using plerixafor at the outset of PBSC mobilization would improve patient acceptability; reduce PBSC collection days and accordingly the patient's costs.

Three adult patients who had never undergone PBSC harvesting were mobilized using subcutaneous (SC) granulocyte-colony stimulating factor (G-CSF) 10 μg/kg daily starting 4 days prior to PBSC harvesting; plus SC plerixafor 240 μg/kg 10 hours prior to PBSC harvesting. Both G-CSF and plerixafor were continued for as long as was required for PBSC collections. Two patients had multiple myeloma (MM) and were both in stringent complete remission (sCR). The third patient suffered from adult-onset spinomuscular atrophy (SMA) and stem cells were required for possible re-infusion therapy. Importantly, the bone marrows of all 3 patients were assessed to be normal prior to PBSC mobilization and collection. The target PBSC CD34 yield was 2 million CD34 cells/kg per PBSC collection.

As can be seen, the CD34 yields (expressed as x million CD34 cells/kg) exceeded expectations:

All patients tolerated the procedure very well and were discharged within 24 hrs of completing the final PBSC collection. The only adverse event was grade 1 restless legs syndrome in Patient #1 following the first injection of plerixafor. It was improved with oral diazepam and did not recur. Both patients with MM reported a sense of “rejuvenation” 2-3 weeks after PBSC collection. All patients were pleased with the relatively complication-free procedure.

Upfront collection of PBSCs using G-CSF/plerixafor is both highly effective and safe. There is great patient acceptability as well as much fewer PBSC collection days and an accompanying reduction in procedure costs. The added advantage of using the SPECTRA Optia cell separator is worth further investigations.

Off Label Use: Plerixafor (MOZOBIL) - Use in patients who had never undergone stem cell collection..