Successful mobilization of peripheral blood stem cells in heavily pretreated myeloma patients with G-CSF alone

 We investigated the feasibility of mobilizing peripheral blood stem cells (PBSC) with G-CSF alone in 24 patients with multiple myeloma. The median age was 53 years (range 33–62). All patients had stage II/III disease and responded to standard first-line (n=6) or salvage chemotherapy (n=18). The median number of previous chemotherapy cycles was 7 (4–18) and the median number of prior melphalan-cycles was 6 (0–14). Nine (35%) patients had experienced prior radiation therapy. The patients received either 10 μg/kg G-CSF (n=18) or 24 μg/kg G-CSF (n=7, including one patient with previous 10 μg/kg G-CSF stimulation) daily s.c. for 5 or more consecutive days until completion of harvesting, starting apheresis on the fifth day. G-CSF treatment was well tolerated, with only slight bone pain in half of the patients (51%). After a median of three (range 1–7) apheresis procedures, medians of 3.8 (0.3–17)×10⁶ CD34+ cells/kg, 8.5 (4.5–24)×10⁸ MNC/kg, 2.9 (0.6–39.4)×10⁴ CFU-GM/kg, and 5.6 (0.9–49)×10⁴ BFU-E/kg were harvested. Three patients (12%) with extensive melphalan pretreatment failed the target collection of at least 2.0×10⁶ CD34+ cell/kg. Pretreatment with six or more cycles of melphalan yielded a smaller number of CD34+ cells than pretreatment with fewer than six cycles (2.5 vs 5.3×10⁶/kg;p=0.001). Nineteen patients underwent high-dose chemotherapy consisting of either total marrow irradiation (9 Gy)/busulfan (12 mg/kg) and cyclophosphamide (120 mg/kg) (n=10), or busulfan (14 mg/kg)/cyclophosphamide (120 mg/kg) (n=5), or tandem melphalan (200 mg/m²). The median time for granulocyte (>1.0/nl) and platelet (>50/nl) recovery was 10 and 14 days (ranges 7–12 and 8–40), respectively. G-CSF alone is a safe, alternative approach to mobilizing sufficient PBSC in patients with multiple myeloma and allows an exact prediction of harvest time. G-CSF-mobilized PBSCs ensure rapid engraftment after myeloablative therapy. Melphalan treatment should be avoided in patients who are candidates for high-dose chemotherapy. Received: February 5, 1998 / Accepted: April 14, 1998     

Stem cell mobilization in resistant or relapsed lymphoma: superior yield of progenitor cells following a salvage regimen comprising ifosphamide, etoposide and epirubicin compared to intermediate-dose cyclophosphamide

We analysed the factors influencing the efficacy of peripheral blood stem cell (PBSC) collection in patients with lymphoma. Sixty-six patients underwent initial PBSC collection following mobilization with chemotherapy plus recombinant granulocyte colony-stimulating factor (300 μg/d). Patients were mobilized with one of two chemotherapy regimens, either cyclophophamide (3 g/m² or 4 g/m²) (n=50) or ifosphamide, etoposide and epirubicin (IVE; n=16). The target of collecting >2.0×10⁶ CD34⁺ cells/kg was achieved in 43/66 (65%) patients with a median of two apheresis procedures. The IVE plus G-CSF mobilization regimen gave a significantly higher median yield of CD34⁺ cells (8.62 × 10⁶/kg) compared with cyclophosphamide plus G-CSF (3.59 × 10⁶/kg) (P=0.045). The median yield of CD34⁺ cells per leukapheresis was almost twice as high in patients receiving IVE (1.94 × 10⁶/kg) compared to cyclophosphamide (1.03 ×10⁶/kg) (P= 0.035). In a univariate analysis of the factors affecting mobilization, the subtype of lymphoma (high-grade NHL) and the mobilization regimen were the only factors associated with high CD34⁺ cell yield. However, in a multivariate analysis of factors affecting mobilization including age, lymphoma subtype, previous chemotherapy and radiotherapy, only the use of the IVE protocol was predictive of a high yield of CD34⁺ cells. In 13 patients undergoing a second mobilization procedure the use of IVE was associated with a significantly higher yield of CD34⁺ cells compared to cyclophosphamide; three patients who failed cyclophosphamide plus G-CSF mobilization were able to proceed to transplantation following success-ful mobilization with IVE + G-CSF. These results demon-strate that IVE is a highly effective mobilization regimen which is superior to cyclophophamide and has the benefit of being effective salvage therapy for lymphoma patients.     

Effects of G-CSF administration and peripheral blood progenitor cell collection in 20 healthy donors

 The effects of both daily G-CSF administration and subsequent peripheral blood progenitor cell collection (PBPCC) by apheresis on 20 healthy adult donors were studied. All received daily G-CSF (filgrastim) 10 μg/kg for 5–7 days by subcutaneous injection. G-CSF administration was well tolerated, except for moderate bone pain and headache. Peak values of CD34+ cells were observed on days 5 (n=12) or 6 (n=8). In all donors a significant increase in CD3+, CD4+, CD8+, CD19+, and NK cells was observed on day 5 in relation to the baseline values. CD4/CD8 lymphocyte ratio was unmodified by G-CSF. None of the donors required a central venous line for PBPCC. Immediately after PBPCC, a platelet count below 100×10⁹/l was observed in nine of 18 cases, although in all donors platelet counts were over 100×10⁹/l 7 days later. A lymphocytopenia on day 7 following PBPCC was observed, although there was a tendency to achieve baseline values 30–90 days after the procedure. Mean numbers (±SD) of collected cells ×10⁶/kg after a median of two (1–4) apheresis sessions and a median of 20 l (10–40) processed were: CD34+ 5.5 (±2.3), CD3+ 326 (±105), CD4+ 207 (±64), CD8+ 164 (±60), CD19+ 88 (±32), and NK cells 32 (±14). We conclude that G-CSF administration to healthy donors is a well-tolerated procedure which is associated with (a) obtaining a high number of hematopoietic progenitor cells, and (b) a significant increase in T, B, and NK cells in donors' blood. In addition, PBPCC by apheresis results in a moderate, rapidly reversible, and clinically irrelevant thrombocytopenia and a moderate lymphocytopenia, which tends to resolve within 3 months following the procedure. Received: 28 December 1995/Accepted: 22 January 1996     

Stem cell mobilization with G-CSF alone in breast cancer patients: higher progenitor cell yield by delivering divided doses (2 x 5 microg/kg) compared to a single dose (1 x 10 microg/kg)

We investigated the schedule dependency of G-CSF (10 microg/kg) alone in mobilizing peripheral blood progenitor cells (PBPC) in breast cancer patients. After a median of three cycles (range, 2-6) of anthracycline-based chemotherapy, 49 patients with breast cancer (stage II/III, > or = 10+ Ln n = 36; locally advanced/inflammatory n = 8, stage IV (NED) n = 5) underwent PBPC collection after steady-state mobilization either with 1 x 10 microg/kg (n = 27) or with 2 x 5 microg/kg (n = 22) G-CSF daily for 4 consecutive days until completion of apheresis. Apheresis was started on day 5. Priming with 2 x 5 microg/kg resulted in a higher median number of CD34+ cells (5.8 vs 1.9 x 10(6)/kg, P = 0.003), MNC (6.6 vs 2.6 x 10(8)/kg, P < 0.001) and CFU-GM (6.5 vs 1.3 x 10(4)/kg, P = 0.001) in the first apheresis than with 1 x 10 microg/kg. Also the overall number of collected BFU-E was higher in the 2 x 5 microg group (9.2 vs 3.1 x 10(4)/kg; P = 0.01). After high-dose chemotherapy with cyclophosphamide/thiotepa/mitoxantrone (n = 46) hematopoietic engraftment with leukocyte count > 1.0/nl was reached in both groups after a median of 10 days (range, 8-15) and with platelets count > 50/nl after 12 (range, 9-40) and 13 days (range, 12-41), respectively. A threshold of > 2.5 x 10(6)/kg reinfused CD34+ cells ensured rapid platelet engraftment (12 vs 17 days; P = 0.12). Therefore, the target of collecting > 2.5 x 10(6) CD34+ cells was achieved in 21/27 (80%) patients of the 1 x 10 microg group and in 21/22 (95%) patients of the 2 x 5 microg/kg group with a median of two aphereses (range, 1-4). None in the 10 microg/kg group, but 6/22 (28%) patients in the 2 x 5 microg/kg group required only one apheresis procedure, resulting in fewer apheresis procedures in the 2 x 5 microg/kg group (mean, 1.8 vs 2.3, P = 0.01). These results demonstrate that priming with 10 microg/kg G-CSF alone is well tolerated and effective in mobilizing sufficient numbers of CD34+ cells in breast cancer patients and provide prompt engraftment after CTM high-dose chemotherapy. G-CSF given 5 microg/kg twice daily (2 x 5 microg) leads to a higher harvest of CD34+ cells and required fewer apheresis procedures than when given 10 microg/kg once daily (1 x 10 microg).     

Mobilization and harvesting of peripheral blood stem cells: randomized evaluations of different doses of filgrastim

The effects of different doses of filgrastim on yields of CD34⁺ peripheral blood stem cells were evaluated in patients with breast cancer. 55 were randomized to receive filgrastim 10, 20, 30 or 40 μg/kg/d with more CD34⁺ cells/kg/apheresis harvested after the three highest dose levels. 35 additional patients were randomized to receive 10 or 30 μg/kg. The median number of CD34⁺ cells collected after 10 μg/kg (n= 31) was 0.7 × 10⁶/kg/apheresis (range 0.1–4.4) as compared to 1.2 (range 0.1–6.8) after 30 μg/kg (n= 32) (P= 0.04). Among patients randomized to 10 v 30 μg/kg, more (50%) achieved 5.0 × 10⁶ CD34⁺ cells/kg and less aphereses were required to achieve 2.5 × 10⁶ CD34⁺ cells/kg after the higher dose (P= 0.04). In multivariate analyses, patients receiving 10 μg/kg (n= 31) had lower yields of CD34⁺ cells (P= 0.026) and had a 3.3-fold increase in the probability of not achieving 5.0 × 10⁶ CD34⁺ cells/kg as compared to patients receiving 20–40 μg/kg (n= 59). Patients who had received radiation had a 2.9-fold probability of not achieving 2.5 × 10⁶ CD34⁺ cells/kg. These data suggest that, in patients with good marrow reserves, doses of filgrastim > 10 μg/kg/d mobilized more CD34⁺ cells and may be useful when high numbers of CD34⁺ cells are desired.     

Etoposide (VP-16) plus G-CSF mobilizes different dendritic cell subsets than does G-CSF alone

Dendritic cells (DCs) are antigen-presenting cells that are critical to the generation of immunologic tumor responses. Myeloid DCs (DC1) express myeloid antigen CD11c; lymphoid DCs (DC2) express CD123(+) and are CD11c(-). Analysis of DC subsets from peripheral blood progenitor cells (PBPC) collected from normal donors mobilized with G-CSF shows a predominance of DC2 cells. Whether PBPCs mobilization by chemotherapy yields different subsets of DCs has not been studied. We analyzed DC subsets in apheresis products from 44 patients undergoing autologous stem cell transplantation from 6/00 to 5/01. Patients received either G-CSF alone (10 microg/kg per day, n=11) or etoposide (2 g/m(2)) plus G-CSF (n=33) for progenitor cell mobilization. The patients were apheresed for 2-10 days (median 3) to reach a minimum of 2.0 x 10(6) CD34(+) cells/kg. Patients receiving G-CSF alone mobilized significantly more total DC2s than did those receiving etoposide plus G-CSF (median 6.2 x 10(6)/kg vs 2.9 x 10(6)/kg, P=0.001). The DC2/DC1 ratio was also significantly different in the two groups, with the G-CSF group having a higher ratio (median 1.2 vs 0.4, P<0.001). We conclude that the combination of chemotherapy plus G-CSF yields different mobilized dendritic cell subsets than does G-CSF alone.     

Peripheral Blood Progenitor Cell Collection during Hematopoietic Recovery following Autologous Blood Progenitor Cell Transplantation

Background and objectives: Peripheral blood progenitor cells (PBPC) are increasingly used for autologous transplantation after high-dose radio/chemotherapy in patients suffering from cancer. PBPC are usually collected after mobilization with conventional-dose chemotherapy plus growth factor. However, it is conceivable to perform leukapheresis for the second autograft during recovery of hematopoiesis after the first course of HDCT/ABPCT. Materials and methods: We treated two patients this way. In the first, with germ cell cancer, six 12-liter leukaphereses yielded 1.8×10⁶ CD34+ cells/kg after mobilization with cis-platinum, etoposide and ifosfamide (PEI) plus granulocyte colony-stimulating factor (G-CSF). The second patient, with relapsed Hodgkin's disease, underwent PBPC collection after treatment with dexamethasone, carmustine, etoposide, cytarabine and melphalan (DexaBEAM) plus G-CSF. Due to excellent mobilization, 8.5×10⁶ CD34+ cells/kg were collected by one 12-liter leukapheresis. Both patients then underwent PBPC collection during hematopoietic recovery following HDCT and ABPCT. Results: In patient 1, following HDCT and ABPCT, three 12-liter aphereses resulted in 0.7×10⁶ CD34+ cells/kg. In patient 2, also after HDCT and ABPCT, a second autograft with 3.2×10⁶ CD34+ cells/kg was harvested by a single 10-liter apheresis. No adverse effects were seen in either patient during apheresis following ABPCT. To our knowledge this is the first report dealing with PBCT collection during hematopoietic recovery following HDCT and ABPCT. Conclusions: (1) PBPC harvesting is feasible and well tolerated in this setting. (2) In appropriate patients with efficient PBPC mobilization after conventional-dose chemotherapy, a further PBPC autograft can be collected during recovery of hematopoiesis after ABPCT, serving as a rescue for a second course of HDCT.     

ESHAP plus G-CSF as an effective peripheral blood progenitor cell mobilization regimen in pretreated non-Hodgkin's lymphoma: comparison with high-dose cyclophosphamide plus G-CSF

The ESHAP (etoposide, methylprednisolone, high-dose cytarabine, and cisplatin) regimen has been shown to be effective as an active salvage therapy for lymphoma. Mobilizing stem cells following ESHAP should decrease time to transplantation by making separate mobilizing chemotherapy (MC) unnecessary, while controlling a patient's lymphoma. We therefore assessed the mobilization potential of ESHAP plus G-CSF in 26 patients (ESHAP group) with non-Hodgkin's lymphoma (NHL) and compared these results with those of 24 patients with NHL who received high-dose (4 g/m2l) cyclophosphamide (HDCY) as MC (HDCY group). The age, sex, and radiotherapy to the axial skeleton were well matched between groups, but the number of patients with poor mobilization predictors was higher in the ESHAP group. Significantly higher numbers of CD34+ cells (x 10(6)/kg) (17.1+/-18.8 vs 5.8+/-5.0, P=0.03) and apheresis day 1 CD34+ cells (x 10(6)/kg) (5.5+/-6.6 vs 1.7+/-2.0, P=0.014) were collected from the ESHAP group than from the HDCY group, and the number of patients who achieved an optimal CD34+ cell target of 5 x 10(6)/kg was higher in the ESHAP group (81 vs 50%, P=0.022). Log-rank test revealed that time to target peripheral blood progenitor cell collection (> or =5 x 10(6)/kg) was shorter in the ESHAP group (P=0.007). These results indicate that ESHAP plus G-CSF is an excellent mobilization regimen in patients with relapsed and poor-risk aggressive NHL.     

Peripheral blood progenitor cells mobilized by chemotherapy plus granulocyte-colony stimulating factor accelerate both neutrophil and platelet recovery after high-dose VP16, ifosfamide and cisplatin

Summary. We report on the chemotherapy plus granulocyte colony-stimulating factor (G-CSF) induced mobilization of peripheral blood progenitor cells (PBPCs) and their impact on haematopoietic recovery following high-dose chemotherapy. Twenty-four patients with advanced solid tumours or lymphomas received standard-dose chemotherapy with VP16, ifosfamide and cisplatin (VIP) followed by filgrastim (G-CSF; 5 μg/kg s.c. daily for 14 d) for the prevention of chemotherapy induced neutropenia and for the simultaneous mobilization of PBPCs. Maximal numbers of progenitors of different lineages were reached at day 11 (range 9–14) after VIP chemotherapy. A median of 0·415 × 10⁹/1 CD34⁺ cells (range 0·11–1·98), 9000 CFU-GM/ml (range 2800–17700). 3500 BFU-E/ml (range 400–10800) and 200 CFU-GEMM/ml (range 0–4400) were recruited. One single apheresis yielded a median of 1·6 × 10⁸ mononuclear cells/kg (range 0·2–5·4) or 5·4 × 10⁶ CD34⁺ cells/kg body weight (range 0·2–24·2). Fourteen patients who showed at least a partial remission after two cycles of the standard-dose chemotherapy regimen were subjected to high-dose VIP chemotherapy (cumulative doses of 1500 mg/m² VP16, 12 g/m² ifosfamide and 150 mg/m² cisplatin) with or without PBPC support. The first six patients were treated with growth factors only (IL-3/GM-CSF) and did not receive PBPCs, whereas the following eight patients were supported with PBPCs in addition to IL-3 and GM-CSF. Neutrophil recovery as well as platelet recovery were significantly faster in patients receiving PBPCs with a median of 6·5 d below 0·1 × 10⁹ neutrophils/1 and 3 d below 20 × 10⁹ platelets/1 as compared to 10·5 d and 8 d in control patients receiving growth factors only. The accelerated platelet recovery in patients supported with PBPCs might be explained—in the absence of detectable colony-forming units megakaryocyte—by the presence of glycoprotein IIb/IIIa⁺, non-proliferating endomitotic megakaryocytic precursor cells within G-CSF mobilized PBPCs. Our data demonstrate that chemotherapy plus G-CSF mobilized PBPCs accelerate both neutrophil and platelet recovery after high-dose VIP chemotherapy in patients with solid tumours or lymphomas.     

Preemptive dosing of plerixafor given to poor stem cell mobilizers on day 5 of G-CSF administration

Plerixafor, given on day 4 of G-CSF treatment is more effective than G-CSF alone in mobilizing hematopoietic progenitor cells. We tested a strategy of preemptive plerixafor use following assessment of the peak mobilization response to 5 days of G-CSF. Patients were eligible for plerixafor if, on day 5 of G-CSF, there were <7 circulating CD34+ cells/μL or if <1.3 × 10(6) CD34+ cells/kg were collected on the first day of apheresis. Plerixafor (0.24?mg/kg s.c.) was given on day 5 of G-CSF followed by apheresis on day 6. This was repeated for up to two additional doses of plerixafor. The primary end point of the study was the percentage of patients who collected at least 2 × 10(6) CD34+ cells/kg. Twenty candidates for auto-SCT enrolled on the trial. The circulating CD34+ cell level increased a median of 3.1 fold (range 1-8 fold) after the first dose of plerixafor and a median of 1.2 fold (range 0.3-6.5 fold) after the second dose of plerixafor. In all, 15 out of 20 (75%) patients achieved the primary end point. In conclusion, the decision to administer plerixafor can be delayed until after the peak mobilization response to G-CSF has been fully assessed.     

Granulocyte colony-stimulating factor given in addition to interferon-α to mobilize peripheral blood stem cells for autologous transplantation in chronic myeloid leukaemia

In order to potentially mobilize and harvest the Ph^? cells observed in most patients with chronic myeloid leukaemia (CML) during interferon-α (IF-α) therapy, G-CSF (filgrastim), 5 μg/kg/d, was administered subcutaneously together with IF-α to 30 CML patients in haematological remission but with various degrees of cytogenetic remission, after IF-α therapy. Peripheral blood stem cells (PBSC ) were harvested using standard aphereses from day 5 of G-CSF. Patients underwent one to four (median three) aphereses. Median total yields/kg were 7.6 (range 3.8–25) × 10⁸ MNC, 3.4 (0–140) × 10⁶ CD34⁺ cells, and 17 (1.1–107) × 10⁴ CFU-GM. No patient had a significant increase in the percentage of Ph⁺ cells in the bone marrow under G-CSF therapy. The percentage of Ph⁺ cells in apheresis products tended to decrease between the first and the last apheresis (P = 0.05). 14 patients who were not responsive to IF-α were transplanted after conditioning with busulphan 16 mg/kg and melphalan 140 mg/m². Median time to neutrophils > 0.5 × 10⁹/l was 20 d (16–114 d) and to platelets > 50 × 10⁹/l 18 d (12–149 d). Nine patients had a major cytogenetic response post graft, which correlated with the amount of Ph⁺ cells reinfused with the graft (P = 0.02). We conclude that this procedure is feasible, allowing the harvest of enough PBSC, some of them Ph^? in patients who responded to IF-α, to allow autologous transplantation.     

Increase of monocytes predicts mobilization of peripheral stem and progenitor cells after chemotherapy followed by G-CSF administration

Abstract: Mobilization of primitive haematopoietic cells to the peripheral blood was studied in 25 patients with haematological malignancies. The optimal level of peripheral stem cells (PSC), defined by their surface expression of CD34, was significantly higher after mobilization with G-CSF, either following chemotherapy or alone (median: 123 × 10⁶/l and 143 × 10⁶/l of CD34+ cells respectively) than without administration of G-CSF subsequent to chemotherapy (median: 27 × 10⁶/l of CD34+ cells). An individual variation in when optimal mobilization of CD34+ cells and myeloid progenitors occurs after chemotherapy and G-CSF administration was noted (median: day 12, range 7–24 days), which makes it difficult to predict when PSC collections in a given patient should be performed. In this study, chemotherapy followed by G-CSF administration resulted in a short lasting (2–3 days) peak appearance of CD34+ cells that could predicted by a 2-fold increase in absolute numbers of monocytes, as compared to the previous day. After the peak level of CD34+ cells in the blood was reached, no further increase in monocytes was seen. The identification of an increase in monocytes, to be used as a predictive variable for when optimal mobilization of PSC will occur in a given patient, may be particularly useful in the individual timing of PSC collections from non-hospitalized patients.     

ESHAP + fixed dose G-CSF as autologous peripheral blood stem cell mobilization regimen in patients with relapsed or refractory diffuse large cell and Hodgkin's lymphoma: a single institution result of 127 patients

From 1996 to November 2004, 131 consecutive patients with relapsed or refractory diffuse large cell lymphoma (DLCL) and Hodgkin's lymphoma (HD) received ESHAP as mobilization chemotherapy before autologous peripheral blood stem cell transplant (ASCT). Patients received fixed dose G-CSF 300 microg SC bid starting 24-36 h after finishing mobilizing ESHAP. In all, four patients failed mobilization and are excluded. Characteristics of 127 patients: 68 males: 59 females. DLCL 49: HD 78. Initial stage I:II:III:IV:unknown was 15:34:33:42:3. Median age at ASCT 26 years. Median prior chemotherapy cycles were six [<6 (17 patients), 6-8 (90 patients), >8 (20 patients)]. Median ESHAP cycle used as mobilizer was third. Patients required 1, 2, 3, 4 apheresis were 93:25:8:1. Median total CD34+ cells/kg collected were 6.9 x 10(6) (DLCL 5.17 x 10(6) and HD 7.6 x 10(6)), patients weighing < or = 70 kg (93 patients) 6.54 x 10(6) and >70 kg (34 patients) 7.44 x 10(6) (P = 0.59), one apheresis (93 patients) 8.6 x 10(6)/kg and >1 apheresis (34 patients) 4.5 x 10(6) (P = 0.001). We conclude that ESHAP and G-CSF 300 microg SC bid is an effective mobilizing regimen even in patients >70 kg and most patients require only 1-2 apheresis.     

Factors influencing G-CSF-mediated mobilization of hematopoietic progenitor cells during steady-state hematopoiesis in patients with malignant lymphoma and multiple myeloma

 We retrospectively analyzed factors influencing PBPC mobilization during steady-state hematopoiesis in 52 patients with malignant lymphoma (n=35) or multiple myeloma (n=17) who received 77 cycles of G-CSF (12.5–50 μg G-CSF/kg/day). For 15 of these patients, the first mobilization cycle (12.5 μg G-CSF/kg/day) was followed by a second course with an increased dose of G-CSF (25 or 50 μg/kg/day). Leukapheresis was started on day 4, about 2 h after s.c. G-CSF administration, and repeated on 2–5 consecutive days. CD34+ cells were determined by flow cytometry in each apheresis product and in the peripheral blood prior to G-CSF administration, beginning on day 4. Colony assays were performed on cryopreserved samples prior to autografting. In the 15 patients receiving two mobilization cycles the higher G-CSF dose was associated with higher levels of CD34+ cells, a higher mean yield of CD34+ cells per apheresis (p<0.05), and a higher percentage of successful (>2×10⁶ CD34+ cells/kg) collections (p=0.058). Patients with limited previous cytotoxic therapy (n=19, up to six cycles of a standard regimen such as CHOP and/or less than 20% marrow irradiation) who received a daily dose of 12.5 μg G-CSF/kg had higher levels of circulating CD34+ cells, a higher mean yield of CD34+ cells per apheresis (p<0.05), and a higher percentage of successful collections (p<0.05) compared with patients previously treated with more intensive radiochemotherapy (n=15). Ten of 20 patients (50%) who failed during the first cycle were successful during subsequent cycles with escalated doses of G-CSF. Trough levels of circulating CD34+ cells on day 4 were predictive for success or failure to achieve >2×10⁶ CD34+ cells/kg, especially in heavily pretreated patients. In conclusion, a daily dose of 12.5 μg G-CSF/kg seems sufficient to mobilize PBPC during steady-state hematopoiesis in the majority of patients who have received limited previous radiochemotherapy. Higher doses of G-CSF, up to 50 μg/kg/day, mobilize more PBPC and should be considered for patients previously treated with intensive radiochemotherapy or those failing to mobilize sufficient numbers of CD34+ cells with lower doses of G-CSF. Received: December 15, 1998 / Accepted: April 28, 1999     

Multiple myeloma: reduced plasma cell contamination in peripheral blood progenitor cell collections performed after repeated high-dose chemotherapy courses

The possibility of reducing tumour cell contamination by cytotoxic drug courses prior to peripheral blood progenitor cell (PBPC) collection was evaluated in two consecutives groups of multiple myeloma (MM) patient candidates for autograft. All patients were at disease onset and received two VAD (vincristine, doxorubicin and dexamethasone) courses as initial debulking. In the first group (44 patients), mobilization and harvest were performed ‘upfront’, after a single cyclophosphamide (CY) administration of 4 g/m²; in the second group (17 patients), PBPC were collected at the end of a high-dose sequential chemotherapy programme, including: CY 5 g/m², etoposide (VP16) 2 g/m², a chemotherapy-free interval with three courses of high-dose dexamethasone, a final mobilizing CY at 7 g/m². G-CSF was given following each high-dose cytotoxic drug. Cytofluorimetric analysis was performed to quantify progenitors (CD34⁺ cells) and plasma cells, identified by the high CD38 expression and/or CD38 and CD138 coexpression. Large amounts of PBPC were collected in either group (median harvested CD34⁺/kg: 15.8 × 10⁶ and 13.4 × 10⁶, respectively; P = 0.9). Circulating plasma cells were significantly higher in patients mobilized ‘upfront’ compared to those who received the high-dose sequence (median peak values of CD38^bright/μl: 39 and 10, respectively; P = 0.02); a similar difference was observed in the amount of con-taminating plasma cells in the harvest products (median CD38^bright/kg: 7.4 × 10⁶ and 1.3 × 10⁶, respectively; P = 0.02). The results demonstrate that an in vivo purging approach is feasible in myeloma patients through repeated high-dose chemotherapy courses; this may provide less-contaminated material suitable for further in vitro purging procedures.     

Biosimilar G-CSF versus filgrastim and lenograstim in healthy unrelated volunteer hematopoietic stem cell donors

The World Marrow Donor Organization recommends original granulocyte-colony stimulating factor (G-CSF) for the mobilization of stem cells in healthy unrelated hematopoietic stem cell donors. We report the comparison of a biosimilar G-CSF (Zarzio) with two original G-CSFs (filgrastim and lenograstim) in mobilization in unrelated donors. We included data of 313 consecutive donors who were mobilized during the period from October 2014 to March 2016 at the Medical University of Warsaw. The primary endpoints of this study were the efficiency of CD34+ cell mobilization to the circulation and results of the first apheresis. The mean daily dose of G-CSF was 9.1 μg/kg for lenograstim, 9.8 μg/kg for biosimilar filgrastim, and 9.3 μg/kg for filgrastim (p < 0.001). The mean CD34+ cell number per microliter in the blood before the first apheresis was 111 for lenograstim, 119 for biosimilar filgrastim, and 124 for filgrastim (p = 0.354); the mean difference was even less significant when comparing CD34+ number per dose of G-CSF per kilogram (p = 0.787). Target doses of CD34+ cells were reached with one apheresis in 87% donors mobilized with lenograstim and in 93% donors mobilized with original and biosimilar filgrastim (p = 0.005). The mobilized apheresis outcomes (mean number of CD34+ cells/kg of donor collected during the first apheresis) was similar with lenograstim, biosimilar filgrastim, and filgrastim: 6.2 × 10⁶, 7.6 × 10⁶, and 7.3 × 10⁶, respectively, p = 0.06. There was no mobilization failure in any of the donors. Biosimilar G-CSF is as effective in the mobilization of hematopoietic stem cells in unrelated donors as original G-CSFs. Small and clinically irrelevant differences seen in the study can be attributed to differences in G-CSF dose and collection-related factors. Active safety surveillance concurrent to clinical use and reporting to donor outcome registry (e.g., EBMT donor outcome registry or WMDA SEAR/SPEAR) might help to evaluate the possible short- and long-term complications of biosimilar G-CSF.     

Prognostic Factors of Peripheral Blood Stem Cell Mobilization with Cyclophosphamide and Filgrastim (r-metHuG-CSF): The CD34+ Cell Dose Positively Affects the Time to Hematopoietic Recovery and Supportive Requirements after High-Dose Chemotherapy

To prospectively analyze factors that influence peripheral blood stem cell (PBSC) collection and hematopoietic recovery after high-dose chemotherapy (HDC), 39 patients received cyclophosphamide 4 g/m² and rHuG-CSF (Filgrastim) 5 μg/kg/day. Leukapheresis was started when CD34⁺ cells/mL were > 5 × 10³. A minimum of 2 × 10⁶ CD34⁺ cells/kg was collected. Median steady-state bone marrow CD34⁺ cell percentage was 0.8% (range, 0.1 to 6). Thirtytwo patients received HDC with autologous PBSC transplantation plus Filgrastim.

A median of 2 (range, 0 to 6) leukapheresis per patient were performed and a median of 6.3 × 10⁶ CD34⁺ cells/kg (range, 0 to 44.4) collected; four patients failed to mobilize CD34⁺ cells. The number of cycles of prior chemotherapy had an inverse correlation with the number CD34⁺ cells/kg collected (r =—0.38; p < 0.005). Patients with <7 cycles had a higher predictability for onset of leukapheresis than patients with ³7 (93% versus 50%; p < 0.005). The four patients who failed to mobilize had received ≥7 cycles. The number of CD34⁺ cells/kg infused after HDC had an inverse correlation with days to recovery to 0.5 × 10⁹ neutrophils/L and 20 X 10⁹ platelets/L (r =—0.68 and—0.56; p < 0.005). The effect of these factors on mobilization and hematopoietic recovery were confirmed by multivariate analysis. Requirements for supportive measures were significantly lower in patients given a higher dose of CD34⁺ cells/kg.

Therefore, PBSC collection should be planned early in the course of chemotherapy. Larger number of CD34⁺ cells/kg determined a more rapid hematopoietic recovery and a decrease of required supportive measures.     

Efficacy of further attempts to mobilize CD34+ peripheral stem cells with alternative procedures after primary failure

19 patients who failed the target collection of at least 2.5 x 10(6) CD34+ cells/kg underwent further mobilization procedures either with granulocyte-colony-stimulating factor (G-CSF) alone after failure to chemotherapy plus G-CSF (group 1), or with chemotherapy plus G-CSF (group 2), or with high-dose G-CSF (24 microg/kg) alone (group 3) after failure to respond to standard dose of G-CSF (10 microg/kg) alone. In all groups, an increase in median CD34+ cell yield could be observed following alternative procedures (1.1- to 1.9 x 10(6) kg; p = 0.02). The highest increase in CD34+ cell harvest was achieved in group 1 (0.85 to 2.2 x 10(6) kg), followed by group 2 (1. 2 to 1.7) and group 3 (1.0 to 1.4), but without statistically significant difference between the mobilization technologies. All patients with more than 1.0 x 10(6) CD34+ cells/kg in the first apheresis procedure reached the overall target of 2.5 x 10(6) CD34+ cells/kg after a second or subsequent mobilization procedure. In contrast, only 3 of 8 patients (37%) with less than 1.0 x 10(6) CD34+ cells in the first harvest could reach the target of 2.5 x 10(6) CD34+ cells after further mobilization attempts.     

Successful collection of peripheral blood progenitor cells in patients with acute myeloid leukaemia following early consolidation therapy with granulocyte colony-stimulating factor-supported high-dose cytarabine and mitoxantrone

We evaluated the feasibility of collecting peripheral blood progenitor cells (PBPC) in patients with acute myeloid leukaemia (AML) following two cycles of induction chemotherapy with idarubicin, cytarabine and etoposide (ICE), and one cycle of consolidation therapy with high-dose cytarabine and mitoxantrone (HAM). Thirty-six patients of the multicentre treatment trial AML HD93 were enrolled in this study, and a sufficient number of PBPC was harvested in 30 (83%). Individual peak concentrations of CD34⁺ cells in the blood varied (range 13.1–291.5/μl; median 20.0/μl). To reach the target quantity of 2.5 × 10⁶ CD34⁺ cells/kg, between one and six (median two) leukaphereses (LP) were performed. The LP products contained between 0.2 × 10⁶ and 18.9 × 10⁶ CD34⁺cells/kg (median 1.2 × 10⁶/kg). Multivariate analysis showed that the white blood cell count prior to HAM and the time interval from the start of HAM therapy to reach an unsupported platelet count > 20 × 10⁹/l were predictive for the peak value of CD34⁺ cells in the blood during the G-CSF stimulated haematological recovery. In 16 patients an intraindividual comparison was made between bone marrow (BM) and PBPC grafts. Compared to BM grafts, PBPC grafts contained 14-fold more MNC, 5-fold more CD34⁺ cells and 36-fold more CFU-GM. A CD34⁺ subset analysis showed that blood-derived CD34⁺ cells had a more immature phenotype as indicated by a lower mean fluorescence intensity for HLA-DR and CD38. In addition, the proportion of CD34⁺/Thy-1⁺ cells tended to be greater in the PBPC grafts. The data indicate that sufficient PBPC can be collected in the majority of patients with AML following intensive double induction and first consolidation therapy with high-dose cytarabine and mitoxantrone.     

Mobilization kinetics of peripheral blood progenitor cells after IAPVP-16 salvage chemotherapy plus G-CSF in lymphoproliferative disorders

We have explored the efficacy of salvage chemotherapy combination, IAPVP-16 (ifosfamide 5 g/m2 on day 1; VP-16 100 mg/m2 on days 1-3; ara-C 1.2 g/m2/12 h on days 1 and 2; methylprednisolone 80 mg/m2 on days 1-5) plus G-CSF for PBPC mobilization. This protocol was used in 45 patients with relapsed or refractory lymphoproliferative diseases who underwent 85 leukaphereses. In 41 patients > 2 x 106/kg CD34+ cells were obtained after a median of two procedures. The median number of CD34+ cells harvested was 3.2 x 106/kg per apheresis and 8.4 x 106/kg per patient. Seven of 10 patients who had failed previous mobilization attempts achieved more than 2 x 106 CD34+ cells/kg in a maximum of three aphereses. A history of previous mobilization failure and a low platelet count (<150 x 109/l) negatively influenced the CD34+ cell yield in univariate and multivariate analyses. A good correlation was found between the circulating CD34+ cells/microl and the CD34+ cells and CFU-GM in the leukaphereses products (r = 0.93 and r = 0.73, P < 0.001), and > or =17 CD34+ cells/microl predicted the achievement of > 2 x 106/kg CD34+ cells in a single leukapheresis in more than 90% of cases. IAPVP-16 plus G-CSF may be specially indicated in tandem transplantations or CD34+ selection and in patients who have failed previous mobilization attempts.