Superior efficacy but higher cost of plerixafor and abbreviated-course G-CSF for mobilizing hematopoietic progenitor cells (HPC) in AL amyloidosis

Systematic literature review of evidence in amyloid light-chain amyloidosis

Introduction: Treatment of amyloid light-chain (AL) amyloidosis, a rare disease with a <5-year lifespan, remains challenging. This systematic literature review (SLR) aimed to evaluate the current evidence base in AL amyloidosis. Methods: Literature searches on clinical, health-related quality of life, economic and resource use evidence were conducted using the Embase, MEDLINE and Cochrane databases as well as gray literature. Results: This SLR yielded 84 unique studies from: five randomized controlled trials; 54 observational studies; 12 health-related quality of life studies, none with utility values; no economic evaluation studies; and 16 resource use studies, none with indirect costs. Conclusion: This SLR highlights a paucity of published literature relating to randomized controlled trials, utility values, economic evaluations and indirect costs in AL amyloidosis.

An updated single center experience with plerixafor and granulocyte colony-stimulating factor for stem cell mobilization in light chain amyloidosis

The use of granulocyte-colony stimulating factor (G-CSF) with or without chemotherapy to mobilize hematopoietic progenitor cells (HPCs) can result in significant morbidity in light chain (AL) amyloidosis patients. Plerixafor, a strong inducer and mobilizer of HPCs, can be used as an adjunct to G-CSF to improve mobilization efficiency. We describe the outcomes for combined G-CSF/plerixafor mobilized patients with AL amyloidosis. We reviewed data of 53 consecutive AL amyloidosis patients who underwent combined G-CSF/plerixafor HPC mobilization between May 2011 and October 2017 at our institution. We evaluated patients for HPC collection efficiency, perimobilization toxicity and postautologous hematopoietic cell transplantation (autoHCT) outcomes. Median CD34⁺ cell collection was 12.4 × 10⁶  cells/kg (range 2.5 × 10⁶ to 34.1 × 10⁶  cells/kg) and 45 (85%) patients had collections of ≥5.0 × 10⁶ CD34⁺ cells/kg. There were no mobilization failures or perimobilization mortality. During mobilization, 37 (70%) patients had weight gain (median 1.3 kg, range 0.1-4) but none >10% body weight, 5 (10%) patients had diarrhea, and one patient each had hypotension and cardiac arrhythmia. Among the 31 patients analyzed for CD34 collection efficiency (CE), the median CD34 CE was 47% (range 36-62). At 5 years follow-up 82% and 84% of patients were progression-free and alive, respectively. Our results suggest that G-CSF/plerixafor mobilization is safe, well tolerated, and effective in AL amyloidosis.

Rapid prediction of stem cell mobilization using volume and conductivity data from automated hematology analyzers

BACKGROUND

Rapid analytics to predict circulating hematopoietic stem cells are valuable for optimal management of mobilization, particularly for the use of newer and costly mobilization agents such as plerixafor.

STUDY DESIGN AND METHODS

We used stepwise, linear multiple regression modeling applied to cell population data collected by routine hematology analyzers (Beckman Coulter DxH 800) on patients undergoing autologous stem cell collection (n = 131). Beta coefficients were used to derive a formula for a stem cell index (SCI). We then tested the correlation of SCI with stem cell counts and performance of the SCI as a predictor of poor mobilization with external validation in a separate cohort (n = 183).

RESULTS

The SCI correlated strongly with CD34 counts by flow cytometry (r = 0.8372 in the development cohort, r = 0.8332 in the external validation cohort) and compares favorably with other rapid stem cell enumerating technologies. In the external validation cohort, the SCI performed well as a predictor (receiver operating characteristic area under the curve, 0.9336) of poor mobilization (CD34 count < 10), with a sensitivity of 72% and a specificity of 93%. When prevalence of poor mobilization was 33%, this resulted in a positive predictive value of 83% and a negative predictive value of 87%. The SCI also showed promise in tracking responses to plerixafor administration.

CONCLUSION

The findings demonstrate the utility of the cell population data collected by hematology analyzers to provide rapid data beyond standard complete blood counts, particularly for stem cell count prediction, requiring no additional reagents, specimen, or instrumentation.

Hematopoietic Progenitor Cell Mobilization with Ifosfamide, Carboplatin, and Etoposide Chemotherapy versus Plerixafor-Based Strategies in Patients with Hodgkin and Non-Hodgkin Lymphoma

Studies comparing the efficacy and safety of chemo-mobilization with ifosfamide, carboplatin, and etoposide (ICE) ± rituximab with plerixafor-based approaches in lymphoma patients have not been performed. We analyzed hematopoietic progenitor cell mobilization outcomes in lymphoma patients undergoing chemo-mobilization with ICE (n = 35) compared with either routine plerixafor (n = 30) or "just in time" (JIT) plerixafor-based mobilization (n = 33). Chemo-mobilization provided a significantly higher total CD34(+) cell yield (median collection, 5.35 × 10(6) cells/kg for ICE versus 3.15 × 10(6) cells/kg for routine plerixafor and 3.6 × 10(6) cells/kg for JIT plerixafor, P < .001). The median day 1 yield of CD34(+) cells was not significantly different (median, 2.2 × 10(6) cells/kg in ICE versus 1.9 × 10(6) cells/kg in upfront plerixafor versus 1.7 × 10(6) cells/kg in JIT plerixafor, P = .20). There was no significant difference in the 3 groups in terms of total number of apheresis sessions performed (median, 2 in each group; P = .78). There were no mobilization failures (inability to collect at least 2 × 10(6) cells/kg) in the chemo-mobilization group, whereas 5 patients (16.7%) in the routine plerixafor and 3 patients (9.1%) in JIT group had mobilization failure (P = .04). Mean time to neutrophil engraftment was faster in the chemo-mobilization group, 10.3 days (±1.2) compared with 12.1 days (±3.6) in the routine plerixafor group and 11.6 days (±3.0) in the JIT group (P < .001) and mean time to platelet engraftment was 13.7 days (±.7) in ICE versus 20.3 days (±1.6) in routine plerixafor versus 17.1 days (± .9) in JIT group (P < .001). Red blood cell transfusions were significantly higher in the chemo-mobilization group (34.3% versus 0 versus 3.2% versus 1, P < .001) and so were the platelet transfusions (22.9% versus 0 versus 0, P < .001). Excluding the cost of chemotherapy administration, chemo-mobilization was associated with significantly less mobilization cost (average cost $17,601.76 in ICE versus $28,963.05 in routine and $25,679.81 in JIT, P < .001). Our data suggests that chemo-mobilization with ICE provides a higher total CD34(+) cell yield, lower rates of mobilization failure, faster engraftment, and lower cost compared to plerixafor-based approaches with comparable toxicity profile between the groups, except for higher transfusion requirements with chemo-mobilization.