Reduced-dose plerixafor as a mobilization strategy in autologous hematopoietic cell transplantation: a proof of concept study.

ABSTRACT

BACKGROUND: Autologous stem cell transplantation (ASCT) is an effective treatment for patients with relapsing myeloma or lymphoma, diseases associated with unsuccessful peripheral blood stem cell (PBSC) collection. Plerixafor is a potent mobilizing agent, allowing more CD34+ cells to be obtained; however, the main obstacle for its use is its high cost. Our aim was to demonstrate that of the use of reduced doses of plerixafor (RD-plerixafor) can be sufficient to collect at least 2 × 106 /Kg CD34+ PBSC in patients with multiple myeloma (MM) or lymphoma undergoing ASCT. STUDY DESIGN AND METHODS: Twenty patients were mobilized with filgrastim (10 µg/kg/4 days) plus a single dose of plerixafor 0.12 mg/kg in Day 4. Apheresis collection was performed on Day 5. One vial of plerixafor was used for two patients. Clinicaltrials.gov NCT03244930. RESULTS: Cell mobilization and collection was successful in 85% of patients (≥2 × 106 CD34+ cells per kilogram). The median collected CD34+ cell count was 4.62 × 106 /kg (range, 1.27-24.5). A 4.1-fold-increase in the median CD34+ PBSC pre-count was observed (from 10.4/µl to 42.4/µl) after RD-plerixafor administration. Seven patients had mild to moderate adverse events. CONCLUSION: RD-plerixafor is an effective, safe, and affordable strategy to ensure adequate PBSC mobilization in patients with MM or lymphoma who undergo ASCT.