Efficacy and safety of plerixafor for hematopoietic stem cell mobilization for autologous transplantation in patients with non-Hodgkin lymphoma and multiple myeloma: A systematic review and meta-analysis

Plerixafor and granulocyte colony stimulating factor for poor mobilizers in patients undergoing autologous peripheral hematopoietic stem cell transplantation: Single institution study

Background

Autologous hematopoietic stem cell transplantation (ASCT) has become the mainstay treatment for many hematological malignancies and solid tumors. An adequate number of stem cells must be collected for better ASCT outcomes, which is challenging in 5%-30% of patients. To improve mobilization, plerixafor is used along with granulocyte colony-stimulating factor (G-CSF).

Patients and methods

We conducted a retrospective single center study involving patients who received plerixafor pre-ASCTs between January 2013 and December 2020 at a tertiary care center in Lebanon. We identified a total of 84 consecutive adult patients. All patients identified were poor mobilizers and have eventually received plerixafor either as pre-emptive use before first apheresis in those with peripheral CD34 + of less than 20 cells/ul, or after failure of first apheresis in those with peripheral stem cells (PSC) >2.0 × 106 cells/Kg.

Results

The median age at ASCT was 52.7 years (22-74) with 61% male predominance. Multiple myeloma was the most prevalent disease 64% followed by Lymphoma 32%. The majority of patients were in complete remission 64% at the time of ASCT. Most patients received proteasome inhibitor-based induction therapy 67% and Melphalan-based conditioning therapy 68%. The median follow-up from ASCT was 9 months (1-59). It was noted that greater body mass index (BMI) is a significant factor for better PSC collection whether premobilization (P = 0.003), or post plerixafor mobilization (P = 0.024). Moreover, Multiple Myeloma patients showed better mobilization using Plerixafor (P = 0.049). Using Plerixafor along with G-CSF in poor mobilizers post G-CSF alone showed a statistically significant increase in the collected PSC mean from 0.67 × 106 cells/Kg to 4.90 × 106 cells/Kg (P < 0.001) with a failure rate only for 12 patients (15%). The infusion of PSC > 2.5 × 106 cells/Kg has shown 3 days decrease in time to platelet engraftment (P = 0.021) and a 36% decrease in progression/relapse rate (P = 0.025).

Conclusion

Plerixafor is effective in increasing the PSC yield in poor mobilizers. Low BMI and hematologic malignancies other than Multiple Myeloma are risk factors for poor mobilization. More studies should be performed to establish more risk factors, helping us to identify poor mobilizers more accurately and initiate plerixafor mobilization early on.

Economic evaluation of plerixafor addition in the mobilization and leukapheresis of hematopoietic stem cells for autologous transplantation: a systematic review

INTRODUCTION

Although plerixafor in association with granulocyte colony-stimulating factor (G-CSF) can improve mobilization and collection of hematopoietic stem cells (HSC) by leukapheresis, cost may limit its clinical application. The present study systematically reviews economic evaluations of plerixafor plus G-CSF usage compared to G-CSF alone and compares different strategies of plerixafor utilization in multiple myeloma and lymphoma patients eligible for autologous HSC transplantation.

AREAS COVERED

Relevant economic evaluations, partial or complete, were searched on PubMed, Embase, LILACS, and Cochrane Central Register of Controlled Trials for a period ending 30 June 2021. This systematic review was reported following the PRISMA Statement. Six economic evaluations were included, considering the use of upfront or just-in-time plerixafor compared to G-CSF alone or other plerixafor strategies. Most comparisons showed both increased cost and health benefits with the addition of plerixafor. Most analyses favored just-in-time plerixafor compared to upfront plerixafor, with a probable preference for broader cutoffs for just-in-time plerixafor initiation.

EXPERT OPINION

Plerixafor is a potentially cost-effective technology in the mobilization of HSC in patients with multiple myeloma and lymphomas eligible for autologous HSC transplantation. There is a decreased number of leukapheresis sessions and remobilizations and a higher yield of CD34+ cells.

Impact of Mobilization Strategies on Peripheral Blood Stem Cell Collection Efficiency and Product Quality: A Retrospective Single-Center Study

Autologous stem cell transplantation is routinely used in the management of several hematological diseases, solid tumors, and immune disorders. Peripheral blood stem cell (PBSC) collection performed by apheresis is the preferred source of stem cells. In this study, the potential impact of mobilization regimens on the performance of the Spectra Optia^® continuous mononuclear cell collection system was evaluated. We performed a retrospective data analysis for patients undergoing autologous PBSC collection at the Medical University Vienna, Vienna General Hospital between September 2016 and June 2018. Collections were divided into two main groups according to the mobilization regimen received: without (210 collections) or with (99 collections) plerixafor. Assessed variables included product characteristics and collection efficiency (CE). Overall, product characteristics were similar between the groups. Median CD34+ CE2 was 50.1% versus 53.0%, and CE1 was 66.9% versus 69.9% following mobilization without and with plerixafor, respectively; the difference was not statistically significant. Simple linear regression showed a very weak positive correlation between the mobilization method and CE1 or CE2 (mobilization with plerixafor increased CE2 by 4.106%). In conclusion, the Spectra Optia^® apheresis system led to high CE and a good quality of PBSC products when mobilization regimens with or without plerixafor were used.

Risk Factors and Outcomes of Stem Cell Mobilization Failure in Multiple Myeloma Patients

Introduction

Autologous hematopoietic stem cell transplantation (ASCT) is a well-established treatment for patients with multiple myeloma (MM), and adequate stem cell collection must be assured before ASCT. However, prediction of poor mobilizers (PMs) is still difficult despite several risk factors for mobilization failure having been identified.

Methods

We retrospectively analyzed MM patients at Taipei Veterans General Hospital in Taiwan who underwent stem cell collection between October 2006 and August 2020. A CD34⁺ cell collection of <1 × 10⁶ cells/kg was defined as a mobilization failure. The primary endpoint was mobilization failure. The secondary endpoint was overall survival (OS). Odds ratios (ORs) and 95% confidence intervals (CIs) for mobilization failure were calculated using a logistic regression model. The cumulative incidence of mortality was estimated using the Kaplan-Meier method.

Results

In the multivariate analysis, absolute monocyte count <500/µL (adjusted OR 10.75, 95% CI: 1.82-63.57, p = 0.009), platelet count <150,000/µL (adjusted OR 12.49, 95% CI: 2.65-58.89, p = 0.001) before mobilization, and time interval from diagnosis to stem cell harvest ≥180 days (adjusted OR 7.69, 95% CI: 1.61-36.87, p = 0.011) were risk factors for PMs. PM patients had poorer OS compared to patients with successful stem cell collection in the univariate analysis (log-rank test p = 0.027). The predicted probability of PMs was estimated by the multiple logistic regression model with a sensitivity of 84.6% and a specificity of 84.0%.

Conclusion

Absolute monocyte count <500/µL, platelet count <150,000/µL, and treatment duration more than 180 days before stem cell mobilization are risk factors for unsuccessful stem cell collection. Our prediction models have high sensitivity and specificity for mobilization failure prediction and allow for early interventions for possible PMs.

MEdical Database AnaLysIS of Japanese multiple myeloma patienTs with apheresis #2 (MEDALIST-2): the impact of plerixafor use on costs and healthcare resources during mobilization and stem cell transplantation

Treatment for multiple myeloma (MM) can involve apheresis to mobilize hematopoietic stem cells for later autologous stem cell transplantation (ASCT), which can become costly over time. This retrospective claims database study examined healthcare resource use and medical costs associated with plerixafor, a selective CXCR4 inhibitor that mobilizes hematopoietic stem cells and minimizes apheresis times. Medical data were sampled from Japanese MM patients between April 2017 and September 2019, after the Japanese launch of plerixafor. The study population (190 plerixafor users and 180 non-users) was identified from the Medical Data Vision database, and further stratified into those using granulocyte-colony stimulating factor in monotherapy or in combination with cyclophosphamide to trigger apheresis. A descriptive comparison of patient characteristics, healthcare resource use, and medical costs across the mobilization and ASCT phases indicated plerixafor is associated with higher average total medical costs. However, plerixafor-treated patients received fewer concomitant medications and spent less time in apheresis than non-users. A comparison of non-users with a similar analysis conducted pre-plerixafor launch (2013-2017) showed general improvements to treatment independent of plerixafor. The results of this research can inform guidelines for the role of plerixafor in balancing cost-effectiveness and drug efficacy in MM treatment.

Efficacy of hematopoietic stem cell mobilization regimens in patients with hematological malignancies: a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Efficient mobilization of hematopoietic stem cells (HSCs) from bone marrow niche into circulation is the key to successful collection and transplantation in patients with hematological malignancies. The efficacy of various HSCs mobilization regimens has been widely investigated, but the results are inconsistent.

METHODS

We performed comprehensive databases searching for eligible randomized controlled trials (RCTs) that comparing the efficacy of HSCs mobilization regimens in patients with hematological malignancies. Bayesian network meta-analyses were performed with WinBUGS. Standard dose of granulocyte colony-stimulating factor (G-CSF SD) was chosen as the common comparator. Estimates of relative treatment effects for other regimens were reported as mean differences (MD) or odds ratio (OR) with associated 95% credibility interval (95% CrI). The surface under the cumulative ranking curve (SUCRA) were obtained to present rank probabilities of all included regimens.

RESULTS

Databases searching and study selection identified 44 eligible RCTs, of which the mobilization results are summarized. Then we compared the efficacy of mobilization regimens separately for patients with multiple myeloma (MM) and non-Hodgkin lymphoma (NHL) by including 13 eligible trials for network meta-analysis, involving 638 patients with MM and 592 patients with NHL. For patients with MM, data are pooled from 8 trials for 6 regimens, including G-CSF in standard dose (SD) or reduced dose (RD) combined with cyclophosphamide (CY), intermediate-dose cytarabine (ID-AraC) or plerixafor. The results show that compared with G-CSF SD alone, 3 regimens including ID-AraC + G-CSF SD (MD 14.29, 95% CrI 9.99-18.53; SUCRA 1.00), G-CSF SD + Plerixafor SD (MD 4.15, 95% CrI 2.92-5.39; SUCRA 0.80), and CY + G-CSF RD (MD 1.18, 95% CrI 0.29-2.07; SUCRA 0.60) are associated with significantly increased total number of collected CD34+ cells (× 106/kg), among which ID-AraC + G-CSF SD ranked first with a probability of being best regimen of 100%. Moreover, ID-AraC + G-CSF SD and G-CSF SD + Plerixafor SD are associated with significantly higher successful rate of achieving optimal target (collecting ≥ 4-6 × 106 CD34+ cells/kg). For patients with NHL, data are pooled from 5 trials for 4 regimens, the results show that compared with G-CSF SD alone, G-CSF SD + Plerixafor SD (MD 3.62, 95% CrI 2.86-4.38; SUCRA 0.81) and G-CSF SD plus the new CXC chemokine receptor-4 (CXCR-4) antagonist YF-H-2015005 (MD 3.43, 95% CrI 2.51-4.35; SUCRA 0.69) are associated with significantly higher number of total CD34+ cells collected. These 2 regimens are also associated with significantly higher successful rate of achieving optimal target. There are no significant differences in rate of achieving optimal target between G-CSF SD + Plerixafor SD and G-CSF + YF-H-2015005.

CONCLUSIONS

In conclusion, ID-AraC plus G-CSF is associated with the highest probability of being best mobilization regimen in patients with MM. For patients with NHL, G-CSF in combination with plerixafor or YF-H-2015005 showed similar improvements in HSCs mobilization efficacy. The relative effects of other chemotherapy-based mobilization regimens still require to be determined with further investigations.

Plerixafor use in autologous hematopoietic stem cell mobilization: Experience from a single center in Southern India

BACKGROUND

Plerixafor is used for patients at risk of Stem cell mobilization failure based on clinical factors or low peripheral blood CD34 count. It is also added upfront to any mobilization irrespective of risk factor, but the cost-effectiveness of the approach is an issue. Data on plerixafor in different settings of autologous hematopoietic stem cell (HSC) collection from India are scant. We are hereby reporting the experience of failure/success of mobilization rate and few important significant variables (CD34+ dosage, failed collection) between plerixafor and granulocyte colony-stimulating factor alone groups among autologous hematopoietic stem cell transplantation (aHSCT) at our institute.

METHODS

This was a record-based single-center study on patients who underwent aHSCT from January 2013 to June 2019 at a tertiary care hospital. Descriptive statistics were used for baseline characteristics, transplant-related factors, and peritransplant outcomes. All statistical analyses were performed at the 5% significance level.

RESULTS

During the study duration, a total of 96 patients had undergone autologous hematopoietic stem cell collection (aHSCC), all by peripheral blood stem cell harvest, requiring 131 apheretic collections. Of the total 131 collections in 96 patients, plerixafor was used in 63 apheresis collections (48% of total pheresis) in 40 patients. Among the 40 patients who were administered plerixafor to augment the collection, 34 patients had upfront use of plerixafor. We did not observe any significant adverse event related to plerixafor use.

CONCLUSION

A rational utilization of plerixafor can facilitate the process and logistics of aHSCC outcome.

A concise review on factors influencing the hematopoietic stem cell transplantation main outcomes

BACKGROUND AND AIMS

As a curative procedure, hematopoietic stemcell transplantation (HSCT) is an approved treatment for many malignant orbenign hematologic and non-hematologic diseases. There are different outcomes of HSCT, as well as several parameters influencing these outcomes.

METHODS

We had searched scientific sources like Web ofScience and PubMed with a combination of keywords such as HSCT, engraftment,survival, outcomes, etc. Totally, 80 articles were included.

RESULTS

Here we have reviewed the effective factors onmain outcomes of HSCT including engraftment, survival, graft versus hostdisease, and Mobilization. Also, the prediction of hematological reconstitutionand some novel suggestions leading to better outcomes are reviewed.

CONCLUSION

The study will be applicable for improvedmanagement of autologous and allogeneic HSCT process to increase the procedureefficiency.

Valid Presumption of Shiga Toxin-Mediated Damage of Developing Erythrocytes in EHEC-Associated Hemolytic Uremic Syndrome

The global emergence of clinical diseases caused by enterohemorrhagic Escherichia coli (EHEC) is an issue of great concern. EHEC release Shiga toxins (Stxs) as their key virulence factors, and investigations on the cell-damaging mechanisms toward target cells are inevitable for the development of novel mitigation strategies. Stx-mediated hemolytic uremic syndrome (HUS), characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal injury, is the most severe outcome of an EHEC infection. Hemolytic anemia during HUS is defined as the loss of erythrocytes by mechanical disruption when passing through narrowed microvessels. The formation of thrombi in the microvasculature is considered an indirect effect of Stx-mediated injury mainly of the renal microvascular endothelial cells, resulting in obstructions of vessels. In this review, we summarize and discuss recent data providing evidence that HUS-associated hemolytic anemia may arise not only from intravascular rupture of erythrocytes, but also from the extravascular impairment of erythropoiesis, the development of red blood cells in the bone marrow, via direct Stx-mediated damage of maturing erythrocytes, leading to “non-hemolytic” anemia.