Contributions
Abstract: PB2426
Type: Publication Only
Background
High dose melphalan followed by autologous hematopoietic stem cell transplantation (HSCT) was established as a standard of care for patients under the age of 65 with newly diagnosed multiple myeloma (MM). Current hematopoietic stem cell (HSC) mobilization strategies in patients with MM are based on administration of granulocyte-colony stimulating factor (G-CSF). Intermediate doses (1-5 g/m2) of cyclophosphamide (Cy) are given prior G-CSF in most European transplant centers in order to increase the yield of HSC collection. Nevertheless, mobilization with intermediate doses of cytarabine (AraC) followed by G-CSF was shown to be very effective alternative mobilization regimen (Giebel 2013).
Aims
To retrospectively compare the efficacy and toxicity of two mobilization regimens, Cy + G-CSF and AraC + G-CSF, used in patients with newly diagnosed MM.
Methods
70 consecutive patients with MM (46 males, 24 females, median age of 62 years, from 37 to 71) mobilized between July 2014 and August 2017 either by Cy + G-CSF (n=30), or by AraC + G-CSF (n=40) were included in the analysis. Cy group: Cy 2,5 g/m2 day 1 followed by G-CSF. AraC group: AraC 400 mg/m2/12h day 1-2 followed by G-CSF. In both regimens the G-CSF was given from day 5 until the end of apheresis at the dose of 10 µg/kg/day divided into two daily doses (rounded to the whole ampoules). HSC collections were performed using Spectra Optia cell separator (Terumo BCT, USA). Standard mobilization efficacy (complete blood count, CD34+ cells) and apheresis product quality controls (complete blood count, CD34+ cells, CFU-GM) were performed. The primary endpoint for HSC collection was to harvest ≥10x106 CD34+/kg, which was considered to have enough HSC for 4 high-dose chemotherapies followed by autologous HSCT.
Results
Peak levels of circulating CD34+ cells in peripheral blood were significantly higher in the AraC group compared to Cy group (368 vs. 99 CD34+ cells/µL, means, p<0.0001). Mean number of apheresis per patient was 1.2 in AraC group compared to 2.1 in Cy group. Single apheresis was sufficient to collect target amount of CD34+ cells (≥10x106/kg) in 83% of patients in the AraC group compared to 17% of patients in the Cy group, and ≥10x106 CD34+/kg was collected in 98% patients in the AraC group compared to 57% of patients in Cy group. CD34+ cell yield was significantly higher in the AraC group compared to Cy group (27x106 vs. 5x106 CD34+/kg, means, p<0.0001). Numbers of collected CFU-GM were also significantly higher in the AraC group (404x104/kg vs. 109x104/kg, means, p<0.0001). Mobilizations with AraC were well tolerated. It should be emphasized that 50% of patients from AraC group developed Gr.4 thrombocytopenia compared to 7% in Cy group. This resulted into the higher need of platelet transfusions in the AraC group (48% vs 10% of patients), however no serious hemorrhagic complications were observed. Times to engraftment after transplantations did not differ between both groups of patients.
Conclusion
Mobilization regimen AraC + G-CSF was significantly more efficient compared to commonly used mobilization regimen Cy + G-CSF. Safety profile of AraC is acceptable, except of higher rate of Gr. 4 thrombocytopenia, which resulted in need of platelet transfusions in half of patients mobilized by AraC + G-CSF. We conclude, that mobilization with AraC could be considered as a safe and very efficacious alternative to Cy in patients with MM when more than 2 autologous HSCT are anticipated.
Session topic: 23. Stem cell transplantation - Clinical
Keyword(s): Ara-C (cytarabine), Autologous hematopoietic stem cell transplantation, Cyclophosphamide, Mobilization
Abstract: PB2426
Type: Publication Only
Background
High dose melphalan followed by autologous hematopoietic stem cell transplantation (HSCT) was established as a standard of care for patients under the age of 65 with newly diagnosed multiple myeloma (MM). Current hematopoietic stem cell (HSC) mobilization strategies in patients with MM are based on administration of granulocyte-colony stimulating factor (G-CSF). Intermediate doses (1-5 g/m2) of cyclophosphamide (Cy) are given prior G-CSF in most European transplant centers in order to increase the yield of HSC collection. Nevertheless, mobilization with intermediate doses of cytarabine (AraC) followed by G-CSF was shown to be very effective alternative mobilization regimen (Giebel 2013).
Aims
To retrospectively compare the efficacy and toxicity of two mobilization regimens, Cy + G-CSF and AraC + G-CSF, used in patients with newly diagnosed MM.
Methods
70 consecutive patients with MM (46 males, 24 females, median age of 62 years, from 37 to 71) mobilized between July 2014 and August 2017 either by Cy + G-CSF (n=30), or by AraC + G-CSF (n=40) were included in the analysis. Cy group: Cy 2,5 g/m2 day 1 followed by G-CSF. AraC group: AraC 400 mg/m2/12h day 1-2 followed by G-CSF. In both regimens the G-CSF was given from day 5 until the end of apheresis at the dose of 10 µg/kg/day divided into two daily doses (rounded to the whole ampoules). HSC collections were performed using Spectra Optia cell separator (Terumo BCT, USA). Standard mobilization efficacy (complete blood count, CD34+ cells) and apheresis product quality controls (complete blood count, CD34+ cells, CFU-GM) were performed. The primary endpoint for HSC collection was to harvest ≥10x106 CD34+/kg, which was considered to have enough HSC for 4 high-dose chemotherapies followed by autologous HSCT.
Results
Peak levels of circulating CD34+ cells in peripheral blood were significantly higher in the AraC group compared to Cy group (368 vs. 99 CD34+ cells/µL, means, p<0.0001). Mean number of apheresis per patient was 1.2 in AraC group compared to 2.1 in Cy group. Single apheresis was sufficient to collect target amount of CD34+ cells (≥10x106/kg) in 83% of patients in the AraC group compared to 17% of patients in the Cy group, and ≥10x106 CD34+/kg was collected in 98% patients in the AraC group compared to 57% of patients in Cy group. CD34+ cell yield was significantly higher in the AraC group compared to Cy group (27x106 vs. 5x106 CD34+/kg, means, p<0.0001). Numbers of collected CFU-GM were also significantly higher in the AraC group (404x104/kg vs. 109x104/kg, means, p<0.0001). Mobilizations with AraC were well tolerated. It should be emphasized that 50% of patients from AraC group developed Gr.4 thrombocytopenia compared to 7% in Cy group. This resulted into the higher need of platelet transfusions in the AraC group (48% vs 10% of patients), however no serious hemorrhagic complications were observed. Times to engraftment after transplantations did not differ between both groups of patients.
Conclusion
Mobilization regimen AraC + G-CSF was significantly more efficient compared to commonly used mobilization regimen Cy + G-CSF. Safety profile of AraC is acceptable, except of higher rate of Gr. 4 thrombocytopenia, which resulted in need of platelet transfusions in half of patients mobilized by AraC + G-CSF. We conclude, that mobilization with AraC could be considered as a safe and very efficacious alternative to Cy in patients with MM when more than 2 autologous HSCT are anticipated.
Session topic: 23. Stem cell transplantation - Clinical
Keyword(s): Ara-C (cytarabine), Autologous hematopoietic stem cell transplantation, Cyclophosphamide, Mobilization