Successful Engraftment of Autologous Peripheral Blood Progenitor Cells Derived from Multiple Collections in Poor Mobilizers by Hyperstimulation with G-CSF.

G-CSF alone or in conjunction with chemotherapy is the most commonly used regimen to mobilize hematopoietic progenitor cells into peripheral blood (PB) for stem cell harvest. However, in about 10–30 % of patients when mobilized with this regimen, their hematopoietic progenitor cells are not effectively mobilized. We have adopted an approach of using higher doses of G-CSF from 16 to 36 ug/kg patient body weight to mobilize hematopoietic progenitor cells in patients that are poorly mobilized. Poor mobilization (PM) is defined as peak pre-apheresis PBCD34 count of 500/uL, and platelet engraftment as a platelet count >20,000/uL without platelet transfusions for 2 consecutive days, respectively, as well as day 15 lymphocyte count. Safety of stem cell mobilization, apheresis collection, and stem cell infusion were also evaluated. The results are shown in the tables below. | Groups | I (GM + L) | II (GM + H) | III (PM + L) | IV (PM + H) | |:----------------------------------------------------------------------------------------- | -------------- | -------------- | ------------- | --------------- | | L: low dose G-CSF (5-12 ug/kg); H: high dose G-CSF (15-36 ug/kg). Median (Range); No. (%) | | No. (patients/collections) | 232/485 | 62/273 | 10/40 | 56/290 | | Peak PBCD34 (/uL) | 85 (21-1320) | 30 (21-99) | 17 (11-20) | 13.5 (5-20) | | CD34 yield (10^6) per recipient Kg wt/apheresis | 3.7 (0.4-37.8) | 1.2 (0.2-11.1) | 1 (0.4-2.7) | 0.7 (0.1-2.89) | | Total CD34 yield (10^6) per recipient kg wt | 9.5 (3.2-37.8) | 6.1 (3.2-17.9) | 4.6 (2.2-7.2) | 4.4 (1.08-6.66) | | GCSF toxicity (Pain, headache, etc) | | | | | | None | 230 (47.4%) | 161 (59%) | 18 (45%) | 158 (54.5%) | | Mild, no pain meds | 155 (32%) | 80 (29.3%) | 18 (45%) | 77 (26.6%) | | Moderate, requiring NSAIDS | 49 (10.1%) | 23 (8.4%) | 1 (2.5%) | 31 (10.7%) | | Severe, requiring Narcotics | 51 (10.5%) | 9 (3.3 %) | 3 (7.5%) | 24 (8.3%) | | Apheresis Toxicity (none) | 87.8% | 89.4% | 85% | 89% | | Apheresis Toxicity (mild to moderate) | 12.2% | 10.6% | 15% | 11% | Efficacy and safety of stem cell mobilization and collection | Groups | I | II | III | IV | |:------------------------------------------- | -------------- | ---------------- | ---------------- | ---------------- | | Median (Range) | | No. (Patients /Infusions) | 232/249 | 48/54 | 8/8 | 32/32 | | Total CD34 (10^6)/recipient kg wt infused | 5.8 (2.5-18.9) | 4.7 (2.0-8.8) | 4.1 (2.1-5.9) | 3.5 (2.4-5.8) | | Days to ANC of 500 | 10 (7-16) | 10 (7-12) | 10 (9-12) | 10 (6-12) | | Days to platelet of 20,000/uL | 10 (6-33) | 10 (8-30) | 13 (8-34) | 10 (8-24) | | Day 15 (+/− 3) lymphocyte count (x 1000/uL) | 0.53 (0-2.96) | 0.38 (0.01-1.25) | 0.43 (0.24-0.75) | 0.74 (0.22-3.69) | | DMSO toxicity (none) | 93.6% | 77.8% | 75% | 90.6% | | DMSO toxicity (yes) | 6.4% | 22.2% | 25% | 9.4% | Efficacy and safety of stem cell infusion and engraftment In summary, multiple collections of autologous peripheral blood progenitor cells through hyperstimulation by G-CSF in poor mobilizers is an effective alternative approach for stem cell harvest. This approach results in successful engraftment, and is safe and well tolerated by patients.