Etoposide + cytarabine plus granulocyte colony-stimulating factor mitigates daratumumab-associated impairment on stem cell mobilization in newly diagnosed multiple myeloma.

Abstract

Daratumumab (dara) and lenalidomide (lena) have been reported to be associated with impaired stem cell mobilization. In this study, we evaluated the mobilization efficiency of etoposide + cytarabine (EA) plus granulocyte colony-stimulating factor (G-CSF) regimen in patients with newly diagnosed multiple myeloma (MM) receiving dara-lena based (n = 38) or lena-based induction therapy (n = 68). The median total CD34+ cells collection was 18.89 × 10⁶/kg in the dara-lena group and 25.59 × 10⁶/kg in the lena group. All patients were successfully mobilized and most patients (≥94%) harvested ≥5 × 10⁶ CD34+ cells/kg in the two cohorts. In the dara-lena group, 89.5% of patients achieved at least 10 × 10⁶ CD34+ cells/kg, the optimal threshold for tandem transplantation, compared with 92.6% in the lena group. Patients receiving more than eight doses of dara showed a reduced CD34+ cell collection. The median time to neutrophil recovery post-autologous stem cell transplantation (ASCT) was delayed in the dara-lena group compared with the lena group (12 versus 11 days, P = 0.007), whereas a similar trend was observed for platelet recovery. EA plus G-CSF was highly effective in achieving optimal CD34+ cell yields in patients treated with MM who were treated with dara-based induction regimens and may be preferred for those planned for tandem ASCT or at high risk of mobilization failure.