Plerixafor in association with R-DHAP and G-CSF to mobilize a large number of CD34 + cells in patients with relapsed-refractory diffuse large B-cell lymphomas.

Lymphoma and plasma cell disorders are the most common indications for autologous hematopoietic stem cell (HSC) transplantation. We conducted a prospective multicenter study with the aim of testing the feasibility of plerixafor (PLX) in combination with R-DHAP and G-CSF in 37 patients with relapsed refractory diffuse large B-cell lymphoma (R/R DLBCL) in order to collect a large number of HSC with a goal of transplantation. After R-DHAP, daily monitoring of peripheral blood CD34 + cells by flow cytometry was performed starting on day + 13. If, on day + 14, peripheral blood CD34 + cells were > 20 × 10e6/L apheresis was started, if they were < 20 × 10e6/L and WBC > 4.0 × 10e9/L, PLX was administered. Results: The median CD34 + cell count collected was 10.5 × 10e6/kg (range 0-51). 81% of patients achieved the minimum CD34 + target cell count of 6 × 10e6/kg. 66% of patients required only one apheresis to achieve collection goals. The rate of engraftment was 10 days for neutrophils > 0.5 × 10e9/L and 13 days for platelets > 20 × 10e9/L. In conclusion, the addition of PLX to salvage therapy in patients with R/R DLBCL is effective and may be routinely used in the future to increase the number of CD34 + cells collected and minimize the risk of poor mobilization.