Comparison of Patient-Reported Outcomes in 5-Year Survivors Who Received Bone Marrow vs Peripheral Blood Unrelated Donor Transplantation: Long-term Follow-up of a Randomized Clinical Trial

Reliability and Validity of the Modified 7-Day Lee Chronic Graft-versus-Host Disease Symptom Scale

Chronic graft-versus-host disease (cGVHD) adversely affects patient quality of life, functional status, and survival after allogenic hematopoietic cell transplantation. The Lee Symptom Scale is a 30-item scale developed to measure the symptoms of cGVHD. Although the original 30-item scale uses a 1-month recall period, we tested the reliability and validity of a 28-item scale (deleting 2 items based on supportive care needs rather than symptoms) with a 7-day recall period, a format that is more appropriate for use in clinical trials. Results show the modified 7-day scale is reliable and valid in the modern era and may be used to assess the symptom burden of cGVHD in clinical trials. Using the distribution method, a 5- to 6-point difference (half a standard deviation) is considered clinically meaningful.

The MarrowMiner: A Novel Minimally Invasive and Effective Device for the Harvest of Bone Marrow

Bone marrow (BM) is a rich source of hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs), and other important stem/progenitor cells. It is the traditional source of cells used in hematopoietic cell transplantation, which is a proven curative treatment for many blood and immune diseases. BM-derived cells have also been shown to have other diverse clinical uses and are increasingly being used in orthopedic medicine, regenerative medicine, and gene therapy applications. Traditional methods for harvesting BM are crude, tedious, time-consuming, and expensive, requiring multiple bone punctures under general anesthesia with serial small-volume aspirates often diluted with peripheral blood. The MarrowMiner (MM) is a novel device designed for rapid and minimally invasive BM harvest. Here we show the safety and efficacy of the MM in both preclinical and clinical settings. In a large-animal porcine model, the MM enabled effective BM collection with similar total nucleated cell collection and increased colony formation compared with standard methods. The MM was subsequently evaluated in a clinical study showing effective and complication-free anterior and posterior BM collection of 20 patients under only local anesthesia or light sedation. Increased total nucleated and mononucleated cell collection was achieved with the MM compared with standard methods in the same patients. Importantly, stem cell content was high with trends toward increased HSC, MSC, and endothelial progenitor cells with similar T cell content. Given the MM is a novel device approved by the US Food and Drug Administration, enabling safe, effective, and minimally invasive harvest of BM, we anticipate rapid adoption for various applications.

Personalizing rabbit anti-thymocyte globulin therapy for prevention of graft-versus-host disease after allogeneic hematopoietic cell transplantation: is there an optimal dose?

The efficacy of anti-thymocyte globulin (ATG) as prophylaxis for graft-versus-host disease (GVHD) has been investigated by many clinical studies over the past decade, including some randomized controlled trials. Intriguingly, although ATG is commonly used as prophylaxis for GVHD, there is still controversy about the optimal dose of ATG for prophylaxis of GVHD after allogeneic hematopoietic cell transplantation (allo-HCT). Indeed, the dose and formulation of ATG, as well as the degree of clinical benefit, has varied among studies, which makes it difficult to fully determine the clinical benefit of ATG. The aim of this review is to summarize the information regarding the optimal ATG dose of each formulation according to stem cell source, and to discuss how best to determine the personalized optimal dose of ATG in each allo-HCT recipient.

Patient-based prediction algorithm of relapse after allo-HSCT for acute Leukemia and its usefulness in the decision-making process using a machine learning approach

Although allogeneic hematopoietic stem cell transplantation (allo‐HSCT) is a curative therapy for high‐risk acute leukemia (AL), some patients still relapse. Since patients simultaneously have many prognostic factors, difficulties are associated with the construction of a patient‐based prediction algorithm of relapse. The alternating decision tree (ADTree) is a successful classification method that combines decision trees with the predictive accuracy of boosting. It is a component of machine learning (ML) and has the capacity to simultaneously analyze multiple factors. Using ADTree, we attempted to construct a prediction model of leukemia relapse within 1 year of transplantation. With the model of training data (n = 148), prediction accuracy, the AUC of ROC, and the κ‐statistic value were 78.4%, 0.746, and 0.508, respectively. The false positive rate (FPR) of the relapse prediction was as low as 0.134. In an evaluation of the model with validation data (n = 69), prediction accuracy, AUC, and FPR of the relapse prediction were similar at 71.0%, 0.667, and 0.216, respectively. These results suggest that the model is generalized and highly accurate. Furthermore, the output of ADTree may visualize the branch point of treatment. For example, the selection of donor types resulted in different relapse predictions. Therefore, clinicians may change treatment options by referring to the model, thereby improving outcomes. The present results indicate that ML, such as ADTree, will contribute to the decision‐making process in the diversified allo‐HSCT field and be useful for preventing the relapse of leukemia.

Selection of unrelated donors and cord blood units for hematopoietic cell transplantation: guidelines from the NMDP/CIBMTR

Allogeneic hematopoietic cell transplantation involves consideration of both donor and recipient characteristics to guide the selection of a suitable graft. Sufficient high-resolution donor-recipient HLA match is of primary importance in transplantation with adult unrelated donors, using conventional graft-versus-host disease prophylaxis. In cord blood transplantation, optimal unit selection requires consideration of unit quality, cell dose and HLA-match. In this summary, the National Marrow Donor Program (NMDP) and the Center for International Blood and Marrow Transplant Research, jointly with the NMDP Histocompatibility Advisory Group, provide evidence-based guidelines for optimal selection of unrelated donors and cord blood units.

Outcome and Prognostic Factors of High-Risk Acute Myeloid Leukemia After Allogeneic Hematopoietic Stem Cell Transplantation

Background

Allogeneic transplantation remains one of the best therapies for high-risk acute myeloid leukemia (HR-AML).

Material/Methods

This study retrospectively analyzed 126 patients with HR-AML after allogeneic hematopoietic stem cell transplantation (allo-HCST).

Results

The disease-free survival (DFS) rates of 1 year and 3 years were 58.83% (95%CI: 50.75–68.20%) and 53.09% (95%CI: 44.59–63.22%) respectively. The cumulative relapse rates of 1 year and 3 years were 21.1% (95%CI: 14.4–28.8%) and 25.9% (95%CI: 18.1–34.5%) respectively. The cumulative incidences of III to IV acute graft-versus-host disease (aGVHD) for 100 days was 8.70% (95%CI: 4.6–14.5%). The cumulative rate of extensive chronic graft-versus-host disease (cGVHD) for 1-year was 4.1% (95%CI: 1.5–8.7%). The cumulative transplantation related mortality rate of 1 year and 3 years were 20.1% (95%CI: 13.6–27.6%) and 21.0% (95%CI: 14.3–28.6%) respectively. Univariate analysis revealed that lower overall survival was correlated with age, bacterial or fungal infection, disease status at transplantation, III–IV aGVHD, post-transplantation lymphoproliferative disorders (PTLD), white blood cell engraftment, and extramedullary involvement (P<0.05). The results of multivariate analysis were that the aforementioned factors were also related to lower overall survival except for PTLD (P<0.05). The results of univariate and multivariate analysis were that extramedullary involvement, III–IV aGVHD, and status pre-transplantation influenced DFS (P<0.05). The risk factors for relapse were status pre-transplantation and extramedullary involvement by univariate and multivariate analysis (P<0.05).

Conclusions

HR-AML has inferior prognosis. Our study indicated the necessity of achieving remission status prior to hematopoietic stem cell transplantation, and administration of preventive treatments on high-risk patients after hematopoietic stem cell transplantation. In addition, adequate prevention and treatment of complications are needed.

Feasibility and cost analysis of day 4 granulocyte colony-stimulating factor mobilized peripheral blood progenitor cell collection from HLA-matched sibling donors

BACKGROUND

Guidelines recommend treatment with 4-5 days of granulocyte colony-stimulating factor (G-CSF) for optimal donor peripheral blood progenitor cell (PBPC) mobilization followed by day 5 collection. Given that some autologous transplant recipients achieve adequate collection by day 4 and the possibility that some allogeneic donors may maximally mobilize PBPC before day 5, a feasibility study was performed evaluating day 4 allogeneic PBPC collection.

METHODS

HLA-matched sibling donors underwent collection on day 4 of G-CSF for peripheral blood (PB) CD34⁺ counts ≥0.04 × 10⁶/mL, otherwise they underwent collection on day 5. Those with inadequate collected CD34⁺ cells/kg recipient weight underwent repeat collection over 2 days. Transplant and PBPC characteristics and cost analysis were compared with a historical cohort collected on day 5 per our prior institutional algorithm.

RESULTS

Of the 101 patient/donor pairs, 50 (49.5%) had adequate PBPC collection on day 4, with a median PB CD34⁺ cell count of 0.06 × 10⁶/mL. Day 4 donors were more likely to develop bone pain and require analgesics. Median collected CD34⁺ count was significantly greater, whereas total nucleated, mononuclear and CD3⁺ cell counts were significantly lower, at time of transplant infusion for day 4 versus other collection cohorts. There were no significant differences in engraftment or graft-versus-host disease. Cost analysis revealed 6.7% direct cost savings for day 4 versus historical day 5 collection.

DISCUSSION

Day 4 PB CD34⁺ threshold of ≥0.04 × 10⁶/mL identified donors with high likelihood of adequate PBPC collection. Day 4 may be the optimal day of collection for healthy donors, without adverse effect on recipient transplant outcomes and with expected cost savings.

Short-term clinical outcomes after HLA 1-locus mismatched uPBSCT are similar to that after HLA-matched uPBSCT and uBMT

In Japan, use of unrelated peripheral blood stem cell transplantation (uPBSCT) from HLA-mismatched unrelated donors has recently been approved. We compared outcomes between HLA-matched and 1-locus mismatched uPBSCT, as well as the impact of HLA disparity in uPBSCT and in unrelated bone marrow transplantation (uBMT). In total, 5862 uBMT recipients and 234 uPBSCT recipients were included. In terms of HLA allele disparity, 185 uPBSCT patients (79.1%) had no HLA mismatch, and 49 (20.9%) had 1-locus mismatch; in comparison, 3585 uBMT patients (61.2%) had no HLA mismatch, and 2277 (38.8%) had 1-locus mismatch. The impact of 1-locus mismatch as compared with match in uPBSCT was not significantly higher than in uBMT [hazard ratio (HR) = 1.02 and 1.27 for grade III-IV acute graft-versus-host disease, HR = 0.98 and 1.14 for non-relapse mortality, and HR = 0.87 and 1.06 for overall survival, respectively]. In conclusion, the impact of single-locus mismatch on short-term outcomes was comparable in uPBSCT and uBMT. Larger studies with longer follow-up are needed to assess long-term outcomes.

Hematopoietic Cell Transplant (HCT) in the Elderly: Myths, Controversies and Unknowns

The incidence of most hematological malignancies increases with age. Despite the higher incidence of hematological malignancies in the elderly, the geriatric population is poorly represented in the early oncology clinical trials that established the current standards of care. Hematopoietic cell transplant (HCT), either upfront or at relapse, provides a potentially life-prolonging, often curative option for many patients with hematological malignancies and is considered the standard of care, at least for younger patients. Historically, the concern that older adults undergoing HCT may experience higher morbidity and transplant-related complications has limited the use of this potentially curative option to younger adults, particularly in allogeneic (allo-) HCT. There is growing evidence to support the feasibility, tolerability, and relatively similar effectiveness of both autologous and allo-HCT in the geriatric population. In the allo-HCT setting, nonmyeloablative/reduced-intensity conditioning (NMA/RIC) has expanded the spectrum of patients that can be considered for this approach. Overall survival is largely affected by disease stage, performance status, and comorbidities rather than by chronological age per se. Comprehensive geriatric assessment (CGA) is a promising tool that can uncover frequently undocumented vulnerabilities in an elderly transplant-eligible patient. Serial study of CGA throughout the peri-HCT period may help predict the short- and long-term impact of HCT on an older adult's functional status and quality of life. Further research is needed to evaluate whether early intervention to improve such vulnerabilities can improve survival and quality of life of these older patients.

Hematopoietic Stem Cell Transplantation in the Era of Engineered Cell Therapy

PURPOSE OF REVIEW

Cellular therapy using T cells modified to express chimeric antigen receptors (CAR-T cells) has had striking success in patients that have failed previous treatment for CD19+ B cell non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia (CLL), or acute lymphoblastic leukemia (ALL). Curative therapy for this group of diseases has previously been limited to allogeneic hematopoietic cell transplantation HCT (alloHCT). The recent results of CAR-T cell therapy raise the question of how best to integrate CAR-T cell therapy and alloHCT in the care of these patients.

RECENT FINDINGS

Within the past 2 years, results from larger trials and increased follow-up of patients treated with CD19 CAR-T cell therapy suggest that some may achieve durable remission without transplant. The balance of efficacy and toxicity for CAR-T cell therapy and alloHCT vary by disease type, disease status at the time of treatment, patient characteristics, and the specific therapy employed. There are early signals that subsequent transplantation of patients who have achieved remission with CAR-T may be a potentially viable (though expensive) strategy.

Flt3L Treatment of Bone Marrow Donors Increases Graft Plasmacytoid Dendritic Cell Content and Improves Allogeneic Transplantation Outcomes

A higher number of donor plasmacytoid dendritic cells (pDCs) is associated with increased survival and reduced graft-versus-host disease (GVHD) in human recipients of unrelated donor bone marrow (BM) grafts, but not granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood grafts. We show that in murine models, donor BM pDCs are associated with increased survival and decreased GVHD compared with G-CSF-mobilized pDCs. To increase the content of pDCs in BM grafts, we studied the effect of FMS-like tyrosine kinase 3 ligand (Flt3L) treatment of murine BM donors on transplantation outcomes. Flt3L treatment (300 μg/kg/day) resulted in a schedule-dependent increase in the content of pDCs in the BM. Mice treated on days -4 and -1 had a >5-fold increase in pDC content without significant changes in numbers of HSCs, T cells, B cells, and natural killer cells in the BM graft. In an MHC-mismatched murine transplant model, recipients of Flt3L-treated T cell-depleted (TCD) BM (TCD F-BM) and cytokine-untreated T cells had increased survival and decreased GVHD scores with fewer Th1 and Th17 polarized T cells post-transplantation compared with recipients of equivalent numbers of untreated donor TCD BM and T cells. Gene array analyses of pDCs from Flt3L-treated human and murine donors showed up-regulation of adaptive immune pathways and immunoregulatory checkpoints compared with pDCs from untreated BM donors. Transplantation of TCD F-BM plus T cells resulted in no loss of the graft-versus-leukemia (GVL) effect compared with grafts from untreated donors in 2 murine GVL models. Thus, Flt3L treatment of BM donors is a novel method for increasing the pDC content in allografts, improving survival, and decreasing GVHD without diminishing the GVL effect.

Antithymocyte globulin for graft-versus-host disease prophylaxis: an updated systematic review and meta-analysis

Graft-versus-host disease (GVHD) remains a limiting factor for successful allogeneic hematopoietic cell transplantation (allo-HCT). Conflicting data exist on the benefit of ATG on post-transplant survival. We performed a systematic review of randomized controlled trials (RCTs) to assess benefits and harms of thymoglobulin and Fresenius (re-branded as Grafalon) ATG formulations in patients undergoing allo-HCT for a variety of hematologic malignancies and bone marrow failure syndromes. A comprehensive search of MEDLINE, EMBASE, and Cochrane Library was performed. Data on methodological quality, benefits, and harms were extracted for each trial and pooled under a random-effects model. Eight RCTs (1134 patients) met the inclusion criteria. Methodological quality ranged from moderate to very low. Pooled results showed no difference in overall survival (OS) with the use of ATG (hazard ratio (HR) = 0.97; 95% confidence interval (CI) = 0.74-1.28; P = 0.83). ATG reduced grade II/III acute GVHD (risk ratio (RR) = 0.61; 95% CI = 0.48-0.77; P < 0.0001), grade III/IV acute GVHD (RR = 0.52; 95% CI = 0.34-0.81; P = 0.004), and chronic GVHD (RR = 0.52; 95% CI = 0.40-0.69; P < 0.00001) without an increase in non-relapse mortality (NRM) (RR = 0.91; 95% CI = 0.74-1.13; P = 0.40). Future studies with better methodological quality are needed to provide conclusive answers related to optimal dosing and timing of ATG for prevention of GVHD.

Disability related to chronic graft -versus-host disease after alternative donor hematopoietic cell transplantation

We determined the incidence of disability related to chronic graft-versus-host disease (bronchiolitis obliterans, grade ≥2 keratoconjunctivitis sicca, sclerotic features or esophageal stricture) for three categories of alternative donor: cord blood, haplorelated marrow or peripheral blood with post-transplant cyclophosphamide, and unrelated single HLA-allele mismatched peripheral blood. Among 396 consecutive hematopoietic cell transplant recipients, 129 developed chronic graft-versus-host disease with 3-year cumulative incidences of 8% for cord blood, 24% for haplorelated grafts, and 55% for unrelated single HLA-allele mismatched peripheral blood. Disability rates were significantly lower for cord blood [hazard ratio (HR) 0.13; 95% confidence interval (CI): 0.1-0.4] and for the haplorelated group (HR 0.31; 95% CI: 0.1-0.7) compared to the rate in the group transplanted with unrelated single HLA-allele mismatched peripheral blood. Cord blood recipients were also >2-fold more likely to return to work/school within 3 years from the onset of chronic graft-versus-host disease (HR 2.54; 95% CI: 1.1-5.7, P=0.02), and the haplorelated group trended similarly (HR 2.38; 95% CI: 1.0-5.9, P=0.06). Cord blood recipients were more likely to discontinue immunosuppression than were recipients of unrelated single HLA-allele mismatched peripheral blood (HR 3.96; 95% CI: 1.9-8.4, P=0.0003), similarly to the haplorelated group (HR 4.93; 95% CI: 2.2-11.1, P=0.0001). Progression-free survival and non-relapse mortality did not differ between groups grafted from different types of donors. Our observations that, compared to recipients of unrelated single HLA-allele mismatched peripheral blood, recipients of cord blood and haplorelated grafts less often developed disability related to chronic graft-versus-host disease, and were more likely to resume work/school, should help better counseling of pre-hematopoietic cell transplant candidates.

Peripheral Blood or Bone Marrow Stem Cells? Practical Considerations in Hematopoietic Stem Cell Transplantation

Although peripheral blood stem cells (PBSC) have worldwide become the predominant source of progenitor cells for hematopoietic stem cell transplantation (HSCT), debate about their role compared with bone marrow (BM) has recently intensified, in large part based on the results of a multicenter Clinical Trials Network study which showed lower incidence of chronic graft-versus-host disease (cGVHD) and improved quality of life in recipients of myeloablative HLA-matched unrelated BM compared with PBSC transplants. However, in certain patient populations, PBSC may lead to improved clinical outcomes due to faster hematologic recovery, a lower risk of graft failure, and possibly a lower probability of relapse. This review will provide a comprehensive summary of studies comparing PBSC with BM as the graft source in terms of acute and chronic GVHD incidence, time to engraftment, and disease-free and overall survival probabilities after HLA-matched related and unrelated donor transplantation and haploidentical donor transplantation. Recommendations based on these studies regarding the use of PBSC versus BM for HSCT are offered.

Allogeneic hematopoietic cell transplantation; the current renaissance

Allogeneic hematopoietic cell transplantation (HCT) provides the best chance for cure for many patients with malignant and nonmalignant hematologic disorders. Recent advances in selecting candidates and determining risk, procedure safety, utilization in older patients, use of alternative donors, and new or novel application of anti-cancer, immunosuppressive and antimicrobial agents have improved outcomes and expanded the role of HCT in hematologic disorders. Relapse remains the predominant cause of failure but enlightened use of new targeted and immunotherapeutic agents in combination with HCT promises to reduce relapse and further improve HCT outcomes.

Comparison of HLA Allele Mismatch and Antigen Mismatch in Unrelated Bone Marrow Transplantation in Patients with Leukemia

We compared the effect of HLA single-antigen and single-allele mismatched unrelated bone marrow transplantation (UBMT) without in vivo/ex vivo T cell depletion. Becasue a single DRB1 mismatch is preferred among 1-allele or 1-antigen mismatched donors, we performed mismatched allele- or antigen-specific analyses with a single DRB1 mismatch as the reference. In adjusted comparison by multivariate analyses, an HLA-DRB1 single-allele mismatch resulted in a decreased risk of nonrelapse mortality (NRM; relative risk [RR], 1.33; 95% confidence interval [CI], 1.08 to 1.63, P = .006) compared with an HLA-DR single-antigen mismatch and conferred a decreased risk of NRM (RR, 1.25; 95% CI, 1.01 to 1.57; P = .025) and overall mortality (RR, 1.16; 95% CI, 1.00 to 1.37; P = .046) compared with an HLA-C single-antigen mismatch. Relative to an HLA-DRB1 single-allele mismatch, 2-mismatch transplants, including those with 1 or more antigen mismatches, resulted in a significantly increased risk of NRM (1-antigen/1-allele mismatch: RR, 1.68; 95% CI, 1.03 to 2.05; P < .001; 2-antigen mismatch: RR, 1.58; 95% CI, 1.04 to 2.02; P = .001) and overall mortality (1-antigen/1-allele mismatch: RR, 1.27; 95% CI, 1.09 to 1.47; P = .002; 2-antigen mismatch: RR, 1.27; 95% CI, 1.03 to 1.57; P = .02). NRM correlated with the combined number of mismatches and allele or antigen mismatches, with rates of 22%, 27%, 32%, 31%, and 38% at 4years for full match, single-allele mismatch, single-antigen mismatch, 2-allele mismatch, and 2 mismatches that included an antigen mismatch, respectively. Our results support the preference for an allele mismatch rather than an antigen mismatch in unrelated bone marrow donors with 1 DR mismatch or 2 mismatches for T cell-replete UBMT.

Peripheral Blood versus Bone Marrow from Unrelated Donors: Bone Marrow Allografts Have Improved Long-Term Overall and Graft-versus-Host Disease-Free, Relapse-Free Survival

Peripheral blood (PB) and bone marrow (BM) from unrelated donors can serve as a graft source for hematopoietic cell transplantation (HCT). Currently, PB is most commonly used in roughly 80% of adult recipients. Determining the long-term impact of graft source on outcomes would inform this decision. Data collected by the Center for International Blood and Marrow Transplant Research from 5200 adult recipients of a first HCT from an 8/8 or 7/8 HLA antigen-matched unrelated donor for treatment of acute leukemia, chronic myelogenous leukemia, or myelodysplastic syndrome between 2001 and 2011 were analyzed to determine the impact of graft source on graft-versus-host disease (GVHD) relapse-free survival (GRFS), defined as freedom from grade III/IV acute GVHD, chronic GVHD requiring immunosuppressive therapy, relapse, and death, and overall survival. GRFS at 2 years was superior in BM recipients compared with PB recipients (16%; 95% confidence interval [CI], 14% to 18% versus 10%; 95% CI, 8% to 11%; P <.0001) in the 8/8 HLA-matched cohort and 7/8 HLA-matched cohort (11%; 95% CI, 8% to 14% versus 5%; 95% CI, 4% to 7%; P = .001). With 8/8 HLA-matched unrelated donors, overall survival at 5 years was superior in recipients of BM (43%; 95% CI, 40% to 46% versus 38%; 95% CI, 36% to 40%; P = .014). The inferior 5-year survival in the PB cohort was attributable to a higher frequency of deaths while in remission compared with the BM cohort. For recipients of 7/8 HLA-matched grafts, survival at 5 years was similar in BM recipients and PB recipients (32% versus 29%; P = .329). BM grafts are associated with improved long-term GRFS and overall survival in recipients of matched unrelated donor HCT and should be considered the unrelated allograft of choice, when available, for adults with acute leukemia, chronic myelogenous leukemia, and myelodysplastic syndrome.

Acute myeloid leukemia: 2019 update on risk-stratification and management

Outcome in patients with acute myeloid leukemia (AML) ranges from death within a few days of beginning treatment (treatment related mortality, TRM) to likely cure. The major reason patients are not cured is resistance to treatment, often manifested as relapse from remission, rather than, even in older patients, TRM, whose incidence is decreasing. Knowledge of the pre-treatment mutation status of various genes has improved our ability to assign initial treatment and, of particular importance, knowledge of whether patients ostensibly in remission have measurable residual disease should influence subsequent management. Several new drugs have been approved by the FDA and we discuss their role in treatment.

Bone Marrow versus Peripheral Blood from Unrelated Donors for Children and Adolescents with Acute Leukemia

Graft-versus-host disease (GVHD) rates are higher after unrelated donor transplantation; thus, we examined whether there would be differences in transplant outcomes by graft type in children and adolescents with acute leukemia. The primary endpoint was overall survival. We studied 872 patients <18 years old who were transplanted with bone marrow (n = 650) or peripheral blood (n = 222) from unrelated donors. The characteristics of the 2 groups were comparable, except recipients of bone marrow were younger than recipients of peripheral blood (median age, 10 versus 12 years). Grades 2 to 4 (hazard ratio [HR], 1.48; P < .001) and grades 3 and 4 acute (HR, 1.69; P < .001) and chronic GVHD (HR, 1.92; P < .001) were higher with transplantation of peripheral blood than with bone marrow. Although relapse risks were lower after peripheral blood transplants (HR, 0.76; P = .05), transplant-related mortality (HR, 1.91; P = .003) and overall mortality (HR, 1.34; P = .032) were higher than with bone marrow transplants. The 8-year probability of overall survival after transplantation of bone marrow was 47% compared with 42% after peripheral blood. The 8-year probability of leukemia-free survival was 40% after transplantation of bone marrow and peripheral blood. Lower relapse after transplantation of peripheral blood negated the survival advantage after transplantation of bone marrow. The observed higher acute and chronic GVHD seen with peripheral blood suggest cautious use of this graft in children and adolescents with acute leukemia.

Translation of Clinical Research into Practice: An Impact Assessment of the Results from the Blood and Marrow Transplant Clinical Trials Network Protocol 0201 on Unrelated Graft Source Utilization

Barriers and facilitators to adoption of results of clinical trials are substantial and poorly understood. We sought to examine whether the results of the randomized, multicenter Blood and Marrow Transplant Clinical Trials Network (BMT CTN) 0201 study comparing peripheral blood (PB) with bone marrow (BM) stem cells for unrelated donor (URD) hematopoietic cell transplantation (HCT) changed practice from PB to BM graft utilization and explored factors that impact graft selection and translation of research results into practice. The difference between use of URD BM and PB in the 2 years before and after publication of results in 2012 was examined using observational data collected by the Center for Blood and Marrow Transplant Research. A web-based survey of transplant physicians was conducted to understand the change in physician-reported personal and center preferred URD graft. No significant change in use of BM versus PB grafts occurred after 2012. Both BMT CTN participating and nonparticipating centers continued to use PB. Ninety-two percent of respondents were aware of the study results; 18% reported a change in personal and 16% reported a change in their center's practice of requesting BM instead of PB for URD HCT. Patient characteristics and the perception that engaging local champions to increase the evidence uptake were factors associated with personal or center change in practice. Despite awareness of the trial results, fewer than one-fifth of HCT physicians reported practice change in response to the BMT CTN 0201 results. Observational data confirmed no discernible change in practice.

Patient-reported outcomes and health status associated with chronic graft-versus-host disease

Chronic graft-versus-host disease occurs in 20-50% of allogeneic hematopoietic cell transplant survivors. We surveyed patients about their quality of life, symptoms, health status, comorbid conditions and medications. Instruments included the Short-Form-36 (SF-36), the Patient-Reported Outcomes Measurement Information System (PROMIS) Global and PROMIS-29 scales and the Lee Chronic Graft-versus-Host Disease Symptom Scale. Functional status was measured by self-reported Karnofsky performance status and work status. Of 3027 surveys sent to recipients surviving one or more years after transplantation, 1377 (45%) were returned. Among these, patients reported that their chronic graft-versus-host disease was mild (n=257, 18.7%), moderate (n=110, 8.0%) or severe (n=25, 1.8%). Another 377 (27.4%) had never had chronic graft-versus-host disease and 280 (20.3%) had had chronic graft-versus-host disease but it had resolved. We excluded 328 (23.8%) patients who did not answer the questions about chronic graft-versus-host disease. Patients who reported moderate or severe chronic graft-versus-host disease reported worse quality of life, lower performance status, a higher symptom burden and were more likely to be taking prescription medications for pain, anxiety and depression compared to those with resolved chronic graft-versus-host disease. Self-reported measures were similar between patients with resolved chronic graft-versus-host disease and those who had never had it. Our data suggest that the PROMIS measures may be able to replace the SF-36 in the assessment of chronic graft-versus-host disease. Between 26.7-39.4% of people with active chronic graft-versus-host disease were unable to work due to health reasons, compared with 12.1% whose chronic graft-versus-host disease had resolved and 15.4% who had never had chronic graft-versus-host disease. Mouth, eye and nutritional symptoms persisted after resolution of chronic graft-versus-host disease. These results show that better prevention of and treatment for chronic graft-versus-host disease are needed to improve survivorship after allogeneic transplantation.

CD34+ Cell Selection versus Reduced-Intensity Conditioning and Unmodified Grafts for Allogeneic Hematopoietic Cell Transplantation in Patients Age >50 Years with Acute Myelogenous Leukemia and Myelodysplastic Syndrome

Reduced-intensity conditioning (RIC) and T cell depletion (TCD) through CD34⁺ cell selection without the use of post-transplantation immunosuppression are 2 strategies used to reduce nonrelapse mortality (NRM) in older patients after allogeneic hematopoietic cell transplantation (allo-HCT). To compare the efficacy of the RIC and TCD approaches, we evaluated the outcomes of patients age >50 years with acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) who underwent allo-HCT from an HLA-matched donor with one of these strategies. Baseline characteristics were comparable in the patients receiving TCD (n = 204) and those receiving RIC (n = 151), except for a higher proportion of unrelated donors (68% versus 40%; P < .001) and a higher comorbidity burden (Hematopoietic Cell Transplantation Comorbidity Index [HCT-CI] ≥3: 51% versus 38%; P < .001) in the TCD cohort. Analysis of outcomes at 3 years showed a higher chronic graft-versus-host disease (GVHD)/relapse-free survival (CRFS) (51% versus 7%; P < .001), lower incidences of grade II-IV acute GVHD (18% versus 46% at day +180) and chronic GVHD (6% versus 55% at 3 years; P < .001), and a lower incidence of relapse (19% versus 33% at 3 years; P = .001) in the TCD group compared with the RIC group. Relapse-free survival (RFS), overall survival (OS), and NRM were similar in the 2 groups. Combining transplantation approach (RIC versus TCD) and comorbidity burden (HCT-CI 0-2 versus ≥3), patients with an HCT-CI score of 0-2 seemed to benefit from the TCD approach. In conclusion, in this retrospective study, the use of a CD34⁺ cell-selected graft and a myeloablative conditioning regimen was associated with higher CRFS and similar RFS and OS compared with unmodified allo-RIC in patients age >50 years with AML and MDS.

Prospective observational study on the first 51 cases of peripheral blood stem cell transplantation from unrelated donors in Japan

The Japan Marrow Donor Program (JMDP) has facilitated unrelated peripheral blood stem cell transplantation (URPBSCT) since 2010. We conducted a prospective multicenter observational study to evaluate the feasibility of such transplantation. Between 2011 and 2014, 51 patients underwent URPBSCT from 8/8 allele-matched donors for hematological malignancies. The median age of the patients was 50 years; 21 had high-risk disease. Myeloablative conditioning regimens were used in 31 patients, and tacrolimus based graft-versus-host disease (GVHD) prophylaxis was used for all patients. The cumulative rate of engraftment was 96%. With a median follow-up period of 610 days for survivors, 100-day and 1-year overall survival rates were 86 and 59%, respectively. The cumulative incidence of non-relapse mortality and relapse at 1 year were 14 and 35%, respectively. The incidence of grade II to IV acute GVHD at 100 days and extensive type of chronic GVHD at 1 year were 25 and 32%, respectively. The probability of overall survival was comparable with that of bone marrow transplantation from HLA matched-unrelated donors in Japan, although the incidence of chronic GVHD was higher. Further follow-up with more patients is clearly warranted to establish the optimal use of URPBSCT together with the approaches of minimizing chronic GVHD.

CD56bright natural killer regulatory cells in filgrastim primed donor blood or marrow products regulate chronic graft-versus-host disease: the Canadian Blood and Marrow Transplant Group randomized 0601 study results

Randomized trials have conclusively shown higher rates of chronic graft-versus-host disease with filgrastim-stimulated apheresis peripheral blood as a donor source than unstimulated bone marrow. The Canadian Blood and Marrow Transplant Group conducted a phase 3 study of adults who received either filgrastim-stimulated apheresis peripheral blood or filgrastim-stimulated bone marrow from human leukocyte antigen-identical sibling donors. Because all donors received the identical filgrastim dosing schedule, this study allowed for a controlled evaluation of the impact of stem cell source on development of chronic graft-versus-host disease. One hundred and twenty-one evaluable filgrastim-stimulated apheresis peripheral blood and filgrastim-stimulated bone marrow patient donor products were immunologically characterized by flow cytometry and tested for their association with acute and chronic graft-versus-host disease within 2 years of transplantation. The immune populations evaluated included, regulatory T cells, central memory and effector T cells, interferon γ positive producing T cells, invariate natural killer T cells, regulatory natural killer cells, dendritic cell populations, macrophages, and activated B cells and memory B cells. When both filgrastim-stimulated apheresis peripheral blood and filgrastim-stimulated bone marrow were grouped together, a higher chronic graft-versus-host disease frequency was associated with lower proportions of CD56^bright natural killer regulatory cells and interferon γ-producing T helper cells in the donor product. Lower CD56^bright natural killer regulatory cells displayed differential impacts on the development of extensive chronic graft-versus-host disease between filgrastim-stimulated apheresis peripheral blood and filgrastim-stimulated bone marrow. In summary, while controlling for the potential impact of filgrastim on marrow, our studies demonstrated that CD56^bright natural killer regulatory cells had a much stronger impact on filgrastim-stimulated apheresis peripheral blood than on filgrastim-stimulated bone marrow. This supports the conclusion that a lower proportion of CD56^bright natural killer regulatory cells results in the high rate of chronic graft-versus-host disease seen in filgrastim-stimulated apheresis peripheral blood. clinicaltrials.gov Identifier: 00438958.

Mobilized Peripheral Blood Stem Cells Versus Unstimulated Bone Marrow As a Graft Source for T-Cell-Replete Haploidentical Donor Transplantation Using Post-Transplant Cyclophosphamide

Purpose T-cell-replete HLA-haploidentical donor hematopoietic transplantation using post-transplant cyclophosphamide was originally described using bone marrow (BM). With increasing use of mobilized peripheral blood (PB), we compared transplant outcomes after PB and BM transplants. Patients and Methods A total of 681 patients with hematologic malignancy who underwent transplantation in the United States between 2009 and 2014 received BM (n = 481) or PB (n = 190) grafts. Cox regression models were built to examine differences in transplant outcomes by graft type, adjusting for patient, disease, and transplant characteristics. Results Hematopoietic recovery was similar after transplantation of BM and PB (28-day neutrophil recovery, 88% v 93%, P = .07; 100-day platelet recovery, 88% v 85%, P = .33). Risks of grade 2 to 4 acute (hazard ratio [HR], 0.45; P < .001) and chronic (HR, 0.35; P < .001) graft-versus-host disease were lower with transplantation of BM compared with PB. There were no significant differences in overall survival by graft type (HR, 0.99; P = .98), with rates of 54% and 57% at 2 years after transplantation of BM and PB, respectively. There were no differences in nonrelapse mortality risks (HR, 0.92; P = .74) but relapse risks were higher after transplantation of BM (HR, 1.49; P = .009). Additional exploration confirmed that the higher relapse risks after transplantation of BM were limited to patients with leukemia (HR, 1.73; P = .002) and not lymphoma (HR, 0.87; P = .64). Conclusion PB and BM grafts are suitable for haploidentical transplantation with the post-transplant cyclophosphamide approach but with differing patterns of treatment failure. Although, to our knowledge, this is the most comprehensive comparison, these findings must be validated in a randomized prospective comparison with adequate follow-up.

Challenges around Access to and Cost of Life-Saving Medications after Allogeneic Hematopoietic Cell Transplantation for Medicare Patients

Hematopoietic cell transplantation (HCT) is an expensive, medically complicated, and potentially life-threatening therapy for multiple hematologic and nonhematologic disorders with a prolonged trajectory of recovery. Similar to financial issues in other cancer treatments, adverse financial consequences of HCT are emerging as an important issue and may be associated with poor quality of life and increased distress in HCT survivors. Prescription medicine coverage for HCT for Medicare and some Medicaid beneficiaries, especially in the long-term, remains suboptimal because of inadequate payer formularies or prohibitive copays. With an increasing number of older patients undergoing HCT and improvement in the overall survival after HCT, the problem of financial burden faced by Medicare beneficiaries with fixed incomes is going to worsen. In this article, we describe the typical financial burden borne by HCT recipients based on estimated copayment amounts attached to the categories of key medications as elucidated through 2 case studies. We also suggest some possible solutions for consideration to help these patients and families get through the HCT by minimizing the financial burden from essential medications needed during the post-HCT period.

Recipient Immune Modulation with Atorvastatin for Acute Graft-versus-Host Disease Prophylaxis after Allogeneic Transplantation

Atorvastatin administration to both the donors and recipients of matched related donor (MRD) allogeneic hematopoietic cell transplantation (allo-HCT) as acute graft-versus-host disease (GVHD) prophylaxis has been shown to be safe and effective. However, its efficacy as acute GVHD prophylaxis when given only to allo-HCT recipients is unknown. We conducted a phase II study to evaluate the safety and efficacy of atorvastatin-based acute GVHD prophylaxis given only to the recipients of MRD (n = 30) or matched unrelated donor (MUD) (n = 39) allo-HCT, enrolled in 2 separate cohorts. Atorvastatin (40 mg/day) was administered along with standard GVHD prophylaxis consisting of tacrolimus and methotrexate. All patients were evaluable for acute GVHD. The cumulative incidences of grade II to IV acute GVHD at day +100 in the MRD and MUD cohorts were 9.9% (95% confidence interval [CI], 0 to 20%) and 29.6% (95% CI,15.6% to 43.6%), respectively. The cumulative incidences of grade III and IV acute GVHD at day +100 in the MRD and MUD cohorts were 3.4% (95% CI, 0 to 9.7%) and 18.3% (95% CI, 6.3% to 30.4%), respectively. The corresponding rates of moderate/severe chronic GVHD at 1 year were 28.1% (95% CI, 11% to 45.2%) and 38.9% (95% CI, 20.9% to 57%), respectively. In the MRD cohort, the 1-year nonrelapse mortality, relapse rate, progression-free survival, and overall survival were 6.7% (95% CI, 0 to 15.4%), 43.3% (95% CI, 24.9% to 61.7%), 50% (95% CI, 32.1% to 67.9%), and 66.7% (95% CI, 49.8% to 83.6%), respectively. The respective figures for the MUD cohort were 10.3% (95% CI, 8% to 19.7%), 20.5% (95% CI, 7.9% to 33.1%), 69.2% (95% CI, 54.7% to 83.7%), and 79.5% (95% CI, 66.8% to 92.2%), respectively. No grade 4 toxicities attributable to atorvastatin were seen. In conclusion, the addition of atorvastatin to standard GVHD prophylaxis in only the recipients of MRD and MUD allo-HCT appears to be feasible and safe. The preliminary efficacy seen here warrants confirmation in randomized trials.

Late effects of blood and marrow transplantation

Hematopoietic cell transplantation is a curative treatment for a variety of hematologic diseases. Advances in transplantation technology have reduced early transplant-related mortality and expanded application of transplantation to older patients and to a wider variety of diseases. Management of late effects after transplantation is increasingly important for a growing number of long-term survivors that is estimated to be half a million worldwide. Many studies have shown that transplant survivors suffer from significant late effects that adversely affect morbidity, mortality, working status and quality of life. Late effects include diseases of the cardiovascular, pulmonary, and endocrine systems, dysfunction of the thyroid gland, gonads, liver and kidneys, infertility, iron overload, bone diseases, infection, solid cancer, and neuropsychological effects. The leading causes of late mortality include recurrent malignancy, lung diseases, infection, secondary cancers and chronic graft-versus-host disease. The aim of this review is to facilitate better care of adult transplant survivors by summarizing accumulated evidence, new insights, and practical information about individual late effects. Further research is needed to understand the biology of late effects allowing better prevention and treatment strategies to be developed.

Related haploidentical donors are a better choice than matched unrelated donors: Counterpoint

Publisher's Note: This article has a companion Point by Fuchs. Publisher's Note: Join in the discussion of these articles at Blood Advances Community Conversations.

A comparison between allogeneic stem cell transplantation from unmanipulated haploidentical and unrelated donors in acute leukemia

BACKGROUND

In the absence of a HLA-matched related or matched unrelated donor, allogeneic stem cell transplantation (allo-SCT) from mismatched unrelated donors or haploidentical donors are potential alternatives for patients with acute leukemia with an indication to allo-SCT. The objective of this study was to compare the outcome of allo-SCT from T cell-replete haploidentical (Haplo) versus matched (MUD 10/10) or mismatched unrelated donor at a single HLA-locus (MMUD 9/10) for patients with acute leukemia in remission.

METHODS

Two hundred sixty-five adult patients with de novo acute leukemia in first or second remission that received a Haplo-SCT between January 2007 and December 2013 were compared with 2490 patients receiving a MUD 10/10 and 813 receiving a MMUD 9/10. Propensity score weighted analysis was conducted in order to control for disease risk imbalances between the groups.

RESULTS

The weighted 3-year non-relapse mortality and relapse incidence were 29 and 30% for Haplo, 21 and 29% for MUD 10/10, and 29 and 25% for MMUD 9/10, respectively. The weighted 3-year leukemia-free survival (LFS) and overall survival (OS) were 41 and 46% for Haplo, 50 and 56% for MUD 10/10, and 46 and 48% for MMUD 9/10, respectively. Using weighted Cox model, both LFS and OS were significantly higher in transplants from MUD 10/10 compared from those in Haplo but not different between transplants from MMUD 9/10 and Haplo. The type of donor was not significantly associated with neither acute nor chronic graft-versus-host disease.

CONCLUSIONS

Patients with acute leukemia in remission have better outcomes if transplanted from a MUD 10/10. We did not find any significant difference in outcome between transplants from MMUD 9/10 and Haplo, suggesting that both can be equally used in the absence of a 10/10 MUD. KEY POINT 1: Better outcomes using fully (10/10) matched unrelated donor for allo-SCT in acute leukemia in remission. KEY POINT 2: Similar outcomes after allo-SCT from unmanipulated haploidentical graft or mismatched (9/10) unrelated donor in acute leukemia in remission.