Pediatric-inspired therapy compared to allografting for Philadelphia chromosome-negative adult ALL in first complete remission

SOHO State of the Art Updates and Next Questions | Approach to Older Adults With Phildadelphia-Chromosome Negative Acute Lymphoblastic Leukemia

Philadelphia-chromosome-negative (Ph-neg) acute lymphoblastic leukemia (ALL) has historically been associated with poor outcomes in older patients due to adverse disease biology, as well as inferior tolerance of conventional chemotherapy. Fortunately, novel therapies, including inotuzumab ozogamicin, blinatumomab, and venetoclax, are now being incorporated into first-line therapy to improve efficacy and decrease toxicity of initial therapy. Inotuzumab ozogamicin, alone or in combination with low intensity chemotherapy, appears to be best suited for the induction phase of treatment due to efficacy in the setting of high tumor burden. In contrast, blinatumomab may be best suited for consolidation due to superior efficacy in setting of morphologic remission, with or without measurable residual disease (MRD). Venetoclax is being investigated in combination with chemotherapy and can be used for treatment of older adults with both B-cell and T-cell ALL. Ongoing trials incorporating inotuzumab, blinatumomab, and venetoclax demonstrate high rates of MRD-negative complete remissions with low early mortality. Long-term outcomes have been less favorable so far, with several trials reporting nonrelapse mortality during subsequent treatment. Unanswered questions remain regarding the optimal treatment of older adults with Ph-neg ALL, including central nervous system (CNS) prophylaxis, the most appropriate consolidation to minimize toxicity without compromising efficacy, and the role of transplant and cellular therapy. T-cell ALL remains an area of unmet need and effort is required to ensure that therapeutic advances benefit all populations equitably. In this manuscript, we review current data and ongoing trials regarding the treatment of older adults with Ph-neg ALL and define topics for further research.

Leveraging health care technology to improve health outcomes and reduce outcome disparities in AYA leukemia

Significant improvements have occurred for adolescent and young adult (AYA) B-cell acute lymphoblastic leukemia (B-ALL) patients following the widespread adoption of "pediatric-inspired" treatment regimens for AYA patients cared for in adult oncology settings. However, for AYA patients, aged 15 to 39, an outcomes gap remains in B-ALL, necessitating the incorporation of novel therapies into up-front treatment regimens. As a result, clinical trial enrollment remains the current standard of care for AYA B-ALL across disease subtypes when available and accessible. Currently, several up-front trials are looking to incorporate the use of inotuzumab, blinatumomab, and chimeric antigen receptor T-cell therapy into existing chemotherapy backbones for AYA patients, as well as tyrosine kinase inhibitors for both Philadelphia-positive (Ph+) and Ph-like B-ALL. In addition to ongoing attempts to improve up-front treatments by incorporating immunotherapy and targeted approaches, the increased use of next generation sequencing for measurable residual disease evaluation has led to superior risk-stratification and a decreased need to pursue consolidative hematopoietic stem cell transplantation during the first complete remission for many patients.

Effect of BMI on toxicities and survival among adolescents and young adults treated on DFCI Consortium ALL trials

Adolescent and young adults (AYAs) with acute lymphoblastic leukemia (ALL) treated with asparaginase-containing pediatric regimens are commonly overweight or obese. We studied the association of body mass index (BMI) on outcomes of 388 AYAs aged 15 to 50 years treated on Dana-Farber Cancer Institute (DFCI) consortium regimens (2008-2021). BMI was normal in 207 (53.3%) and overweight/obese in 181 (46.7%). Patients who were overweight or obese experienced higher nonrelapse mortality (NRM; 4-year, 11.7% vs 2.8%, P = .006), worse event-free survival (4-year, 63% vs 77%, P = .003), and worse overall survival (OS; 4-year, 64% vs 83%, P = .0001). Because younger (aged 15-29 years) AYAs more frequently had a normal BMI (79% vs 20%, P < .0001), we conducted separate analyses in each BMI group. We found excellent OS among younger and older (30-50 years) AYAs with normal BMI (4-year OS, 83% vs 85%, P = .89). Conversely, in AYAs who were overweight/obese, worse outcomes were seen in older AYAs (4-year OS, 55% vs 73%, P = .023). Regarding toxicity, AYAs who were overweight/obese experienced higher rates of grade 3/4 hepatotoxicity and hyperglycemia (60.7% vs 42.2%, P = .0005, and 36.4% vs 24.4%, P = .014, respectively) but had comparable rates of hypertriglyceridemia (29.5% vs 24.4%, P = .29). In a multivariable analysis, higher BMI was associated with worse OS, hypertriglyceridemia was associated with improved OS, and age was not associated with OS. In conclusion, among AYAs treated on DFCI Consortium ALL regimens, elevated BMI was associated with increased toxicity, increased NRM, and decreased OS. The deleterious effect of elevated BMI was more pronounced in older AYAs.

Comparison of a modified pediatric protocol versus a hyper-CVAD protocol in adolescents and young adults with Philadelphia-negative acute lymphoblastic leukemia: A multicenter retrospective analysis

BACKGROUND

The outcomes of Pediatric acute lymphoblastic leukemia (ALL) have improved dramatically whereas outcomes for ALL amongst adolescents and young adults (AYA) have lagged behind. The introduction of pediatric-like regimens to manage adult ALL has shown promising outcomes across several analyses.

MATERIALS AND METHODS

In this analysis, we aimed to retrospectively compare the differences in outcomes among patients aged 14-40 years with Philadelphia-negative ALL treated with a Hyper-CVAD protocol versus a modified pediatric protocol.

RESULTS

A total of 103 patients were identified with 58 (56.3%) in the modified ABFM group and 45 (43.7%) in the hyper-CVAD group. The median duration of follow-up for the cohort was 39 months (range 1-93). There were significantly lower rates of MRD persistence after consolidation (10.3% vs. 26.7%, P = 0.031) and transplantation (15.5% vs. 46.6%, P < 0.001) in the modified ABFM group. 5-year OS rates (83.9% vs. 65.3%, P = 0.036) and DFS rates (67.4% vs. 44%, P = 0.014) were higher in the modified ABFM groups. The incidence of grade 3 and 4 hepatotoxicity (24.1% vs. 13.3%, P < 0.001) and osteonecrosis (20.6% vs. 2.2%, P = 0.005) were higher in the modified ABFM group.

CONCLUSION

Our analysis demonstrates that the use of a pediatric modified ABFM protocol demonstrated superior outcomes compared to the hyper-CVAD regimen in the treatment of Philadelphia-negative ALL amongst AYA patients. However, the modified ABFM protocol was associated with an increased risk of certain toxicities including high grade liver toxicity and osteonecrosis.

Real-world outcomes of adult patients with acute lymphoblastic leukemia treated with a modified CALGB 10102 regimen

Acute lymphoblastic leukemia (ALL) is an aggressive bone marrow cancer with disparate outcomes. Data on patient outcomes in real world settings outside of clinical trials is limited. The current study reports on outcomes for 137 ALL patients who received an adult induction and consolidation regimen derived from the CALGB 10102 trial modified without alemtuzumab. Of the 137 patients, 32 were < 40 years old, 52 were between 40 and 59, and 53 were ≥ 60 years old. Overall, 109 (79.6%) patients achieved a complete remission (< 40: 96.1%, 40-59: 86.5%, and 62.3% ≥ 60 (p = 0.0002)). Progression free survival for the entire cohort was 13.5 months and by age was 19.8 months for less than 40, 23.4 months for 40 to 59 and 6.7 months for ≥ 60; p = 0.0002. Median survival was 22.1 months for the entire cohort (32.9 months for ages < 40, 26.6 months ages 40-59, 7.8 months ≥ 60, p < 0.001).

Pediatric chemotherapy versus allo-HSCT for adolescent and adult Philadelphia chromosome-negative ALL in first complete remission: a meta-analysis

Pediatric-inspired chemotherapy significantly improves survival for adolescent and adult patients with acute lymphoblastic leukemia (ALL). However, the benefits over allogeneic hematopoietic stem cell transplantation (allo-HSCT) remain unclear. To compare clinical outcomes between pediatric-inspired chemotherapy and allo-HSCT in consolidation therapy of adolescent and adult Philadelphia chromosome-negative (Ph-neg) ALL in first complete remission (CR1), related studies from MEDLINE, Embase, and Cochrane Controlled Register of Trials updated to July 2022 were searched. A total of 13 relevant trials including 3161 patients were included in the meta-analysis. Compared with allo-HSCT, pediatric-inspired chemotherapy achieved better OS (hazard risk (HR), 0.53; 95% confidence interval (CI), 0.41 to 0.68) and DFS (HR, 0.64; 95% CI, 0.48 to 0.86), with a significant reduction in NRM (risk ratio (RR), 0.30; 95% CI, 0.18 to 0.51), but no difference in the relapse rate (RR, 1.13; 95% CI, 0.93 to 1.39). When only studies based on intention-to-treat analysis were included, pediatric-inspired chemotherapy consistently conferred a survival advantage. In subgroup analyses, patients with baseline high-risk features demonstrated similar OS and DFS between pediatric-style chemotherapy and allo-HSCT, while pediatric-style chemotherapy had an OS and DFS advantage in standard-risk subgroup. Particularly, patients with positive minimal residual disease (MRD) achieved better OS and DFS if proceeded to allo-HSCT.

The evolution of acute lymphoblastic leukemia research and therapy at MD Anderson over four decades

Progress in the research and therapy of adult acute lymphoblastic leukemia (ALL) is accelerating. This analysis summarizes the data derived from the clinical trials conducted at MD Anderson between 1985 and 2022 across ALL subtypes. In Philadelphia chromosome-positive ALL, the addition of BCR::ABL1 tyrosine kinase inhibitors (TKIs) to intensive chemotherapy since 2000, improved outcomes. More recently, a chemotherapy-free regimen with blinatumomab and ponatinib resulted in a complete molecular remission rate of 85% and an estimated 3-year survival rate of 90%, potentially reducing the role of, and need for allogeneic stem cell transplantation (SCT) in remission. In younger patients with pre-B Philadelphia chromosome-negative ALL, the integration of blinatumomab and inotuzumab into the frontline therapy has improved the estimated 3-year survival rate to 85% across all risk categories. Our future strategy is to evaluate the early integration of both immunotherapy agents, inotuzumab and blinatumomab, with low-dose chemotherapy (dose-dense mini-Hyper-CVD-inotuzumab-blinatumomab) into the frontline setting followed by CAR T cells consolidation in high-risk patients, without any further maintenance therapy. In older patients, using less intensive chemotherapy (mini-Hyper-CVD) in combination with inotuzumab and blinatumomab has improved the 5-year survival rate to 50%. Among patients ≥ 65-70 years, the mortality in complete remission (CR) is still high and is multifactorial (old age, death in CR with infections, development of myelodysplastic syndrome or acute myeloid leukemia). A chemotherapy-free regimen with inotuzumab and blinatumomab is being investigated. The assessment of measurable residual disease (MRD) by next-generation sequencing (NGS) is superior to conventional assays, with early MRD negativity by NGS being associated with the best survival. We anticipate that the future therapy in B-ALL will involve less intensive and shorter chemotherapy regimens in combination with agents targeting CD19 (blinatumomab), CD20, and CD22 (inotuzumab). The optimal timing and use of CAR T cells therapy may be in the setting of minimal disease, and future trials will assess the role of CAR T cells as a consolidation among high-risk patients to replace allogeneic SCT. In summary, the management of ALL has witnessed significant progress during the past four decades. Novel combination regimens including newer-generation BCR::ABL1 TKIs and novel antibodies are questioning the need and duration of intensive chemotherapy and allogeneic SCT.

PH negative acute lymphoblastic leukemia in adolescents and young adults treated according a MRD adapted BFM ALL IC 2009 protocol: Argentine real-world data on 171 patients

Intensified pediatric chemotherapy regimens to treat adolescents and young adults (AYA) patients with Philadelphia negative acute lymphoblastic leukemia (ALL) have been associated with better outcomes. The local BFM 2009-based scheme complements the risk stratification assessing the measurable residual disease (MRD) along the induction phase with increasing levels of sensitivity. The present retrospective multicenter analysis included 171 AYA (15-40 years) patients treated accordingly between 2013 and 2019. Ninety-one percent obtained morphological complete remission, 67% a negative (<0.1%) MRD at day 33 (TP1), and 78% a negative (<0.01%) MRD at day 78 (TP2). The overall survival (OS) and the event-free survival (EFS) at 2 years were 62%±4.1 and 55%±4.1, respectively. The OS and EFS were significant better for prednisone responders, who achieved <10% BM blast at day 15, a negative MRD at TP1 or at TP2, and for low-risk patients. Age ≤30 years and WBC <30×10⁹/L, particularly among B-phenotype, were also associated with longer OS. In the multivariable analyses, TP1 MRD positive (OS HR 2.8, 95% CI 1.4-5.7, p=0.004; EFS HR 3.0, 95% CI 1.6-5.7, p=0.001) and at TP2 (OS HR 2.6, 95% CI 1.3-5.3, p=0.012; EFS HR 2.6, 95% CI 1.3-5.1, p=0.006) were independently associated with earlier events. Age >30 years was also associated with a shorter survival (HR 3.1, 95% CI 1.3-7.5, p=0.014). Therefore, those 68 patients ≤30 years with TP1/TP2 negative MRD depicted a longer OS (2 years 85%±4.8). Based on our real-world data, the pediatric-based scheme is feasible in Argentina associated with better outcomes for younger AYA patients who achieved negative MRD at day 33 and 78.

Optimal approach to T-cell ALL

T-lineage acute lymphoblastic leukemia (T-ALL) is curable for most children and adolescent and young adult patients with contemporary frontline chemotherapy regimens. During the past decade, improved survival rates have resulted from the optimization of frontline chemotherapy regimens, the use of minimal residual disease (MRD) assessment for evaluating a patient's risk for relapse, and the intensification of treatment based on the persistence of MRD. Optimization of initial therapy is critical because relapsed T-ALL after initial intensive chemotherapy is incurable for most adult patients. Current T-ALL salvage chemotherapy regimens are minimally effective, and unlike in B-cell ALL, there are no approved antibody therapies or chimeric antigen receptor T-cell therapies for relapsed disease. Immunotherapy and small-molecule inhibitors are beginning to be tested in relapsed T-ALL and have the potential to advance the treatment. Until effective salvage strategies are discovered, however, intensive frontline therapy is required for cure. In this article I review the current frontline chemotherapy regimens for adult patients with T-ALL, summarize the novel targeted and immune therapeutics currently in early-phase clinical trials, and outline how these therapies are helping to define an optimal approach for T-ALL.

Optimal approach to T-cell ALL

T-lineage acute lymphoblastic leukemia (T-ALL) is curable for most children and adolescent and young adult patients with contemporary frontline chemotherapy regimens. During the past decade, improved survival rates have resulted from the optimization of frontline chemotherapy regimens, the use of minimal residual disease (MRD) assessment for evaluating a patient's risk for relapse, and the intensification of treatment based on the persistence of MRD. Optimization of initial therapy is critical because relapsed T-ALL after initial intensive chemotherapy is incurable for most adult patients. Current T-ALL salvage chemotherapy regimens are minimally effective, and unlike in B-cell ALL, there are no approved antibody therapies or chimeric antigen receptor T-cell therapies for relapsed disease. Immunotherapy and small-molecule inhibitors are beginning to be tested in relapsed T-ALL and have the potential to advance the treatment. Until effective salvage strategies are discovered, however, intensive frontline therapy is required for cure. In this article I review the current frontline chemotherapy regimens for adult patients with T-ALL, summarize the novel targeted and immune therapeutics currently in early-phase clinical trials, and outline how these therapies are helping to define an optimal approach for T-ALL.

Comparable outcomes in patients with B-cell acute lymphoblastic leukemia receiving haploidentical hematopoietic stem cell transplantation: Pretransplant minimal residual disease-negative complete remission following chimeric antigen receptor T-cell therapy versus chemotherapy

Introduction

Chimeric antigen receptor (CAR) T-cell (CAR-T) therapy followed by haploidentical hematopoietic stem cell transplantation (haplo-HSCT) markedly improves the long-term survival of patients with refractory/relapsed (R/R) B-cell acute lymphoblastic leukemia (B-ALL).

Methods

We performed a parallel comparison of transplant outcomes in 168 B-ALL patients undergoing haplo-HSCT after achieving minimal residual disease (MRD)-negative complete remission (CR) from CAR-T therapy (n = 28) or chemotherapy (n = 140) between January 2016 and August 2021. We further divided the chemotherapy group into the first CR group (chemo+CR1, n = 118) and a second or more CR group (chemo+≥CR2, n = 22).

Results

With a median follow-up period of 31.0 months, the 2-year overall survival (OS), leukemia-free survival (LFS), non-relapse mortality (NRM), and relapse rates in the CAR-T and chemotherapy groups did not differ significantly (OS, 87.9% vs. 71.5 %; LFS, 72.0% vs. 66.8%; NRM, 3.9% vs. 13.7%; relapse, 24.1% vs. 19.4%). Multivariate analysis confirmed that ≥CR2 at transplantation following chemotherapy was an independent risk factor associated with poor OS (hazard ratio (HR) 4.22 [95% CI, 1.34–13.293], p = 0.014) and LFS (HR 2.57 [95% CI, 1.041–6.343], p = 0.041). The probabilities of OS and LFS at 2 years in the CAR-T group were comparable to those in the chemo+CR1 group but significantly higher than those in the chemo+≥CR2 group (OS, 87.9% vs. 37.8%, p = 0.007; LFS, 72.0% vs. 41.7%, p = 0.043). No significant differences in the incidences of NRM were noted among the three groups.

Conclusions

Our results demonstrated that patients with R/R B-ALL receiving haplo-HSCT after CAR-T therapy achieved comparable outcomes to patients transplanted post-chemotherapy-based MRD-negative CR1, without increased risk of transplant-related mortality and toxicity.

Effect of pediatric- versus adult-type chemotherapy regimens on outcomes of allogeneic hematopoietic stem cell transplants for adult T-cell acute lymphoblastic leukemia in first complete remission

The optimal chemotherapy regimen pre-transplantation for adult T-cell acute lymphoblastic leukemia (T-ALL) patients remains unknown. Here, we compared the transplant outcomes in 127 subjects receiving pediatric- (N = 57) or adult-type (N = 70) regimens pre-transplant. The corresponding 3-year cumulative incidences of relapse (CIR) was 7% (95% CI: 3-11%) and 29% (95% CI: 23-35%; P = 0.02), leukemia-free survivals (LFS) was 86% (95% CI: 81-91%) and 57% (95% CI: 51-63%; P = 0.003), overall survivals (OS) was 88% (95% CI: 84-92%) and 58% (95% CI: 52-64%; P = 0.002), the 1-year NRM was 4% (95% CI: 1-7%) and 9% (95% CI: 4-14%; P = 0.40). Multivariate analysis showed that pediatric-type regimen was associated with lower CIR (Hazard Ratio [HR] = 0.31 [95% CI: 0.09-1.00]; P = 0.05), better LFS (HR = 0.34 [95% CI: 0.15-0.78]; P = 0.01) and OS (HR = 0.30 [95% CI: 0.13-0.72]; P = 0.01). Our results suggested that adult T-ALL patients undergoing allo-HSCT might benefit from pediatric-type chemotherapy.

The current treatment approach to adolescents and young adults with acute lymphoblastic leukemia (AYA-ALL): challenges and considerations

INTRODUCTION

AYA-ALL differs from pediatric ALL in terms of clinical, biological, psychosocial factors and access to care and has an inferior outcome. It is now being recognized that pediatric-inspired protocols are superior to adult protocols for this cohort, but given the lack of randomized trials, several questions remain unanswered.

AREAS COVERED

In this review, we discuss how AYA-ALL is different from the pediatric ALL population, compare AYA ALL with ALL in middle and older age adults, review the studies that have enrolled the AYA cohort, summarize risk-stratified and response-adapted approaches, describe the biological subtypes, and review the novel agents/approaches under evaluation.

EXPERT OPINION

AYA-ALL is a complex and challenging disease that needs multidisciplinary and focused care. Well-designed clinical trials that focus on this cohort are needed to further improve the outcomes.

Effect of Treatment in a Specialized Pediatric Hemato-Oncology Setting on 5-Year Survival in Acute Lymphoblastic Leukemia: A Quasi-Experimental Study

Simple Summary

Adolescents and young adults (AYAs) with acute lymphoblastic leukemia (ALL) have a worse prognosis than children. In addition to differences in biology—such as higher incidence of unfavorable genetic alterations in the AYA population—this might be related to the fact that ALL patients under a certain age (often 18 years) are generally treated in special pediatric hemato-oncology settings, which is associated with improved survival, while patients above that age are treated in adult hemato-oncology care settings. Based on previous research, adult treatment settings have increasingly adopted pediatric-inspired protocols, which appear to have led to increased survival of adolescent ALL patients. This study aims to assess whether there remains an effect of treatment of ALL patients in a specialized pediatric hemato-oncology setting on 5-year survival. This study provides insight into the effects of such treatment for ALL patients, and may stimulate further research into causal relationships in other oncological conditions.

Abstract

Survival rates of adolescents and young adults (AYAs) with acute lymphoblastic leukemia (ALL) are inferior to those of pediatric ALL patients. In part, this may be caused by differences in treatment setting. Generally, children are treated in specialized pediatric hemato-oncology settings, whereas AYAs are treated in adult hemato-oncology settings. Since 2005, adult treatment protocols have included pediatric-inspired chemotherapy, which has been the standard of care for AYAs from 2008 onwards. This study aims to assess whether, despite protocols in both settings having become more similar, there remains an effect of treatment in specialized pediatric hemato-oncology settings on 5-year survival for ALL patients in the Netherlands. We used nationwide registry data (2004–2013) on 472 ALL patients aged between 10 and 30 years old. A fuzzy regression discontinuity design was applied to estimate the treatment effect using two-stage least squares regression with the treatment threshold at 17 years and 7 months of age, adjusting for sex, age at diagnosis, and immunophenotype. We found a risk difference of 0.419 (p = 0.092; 95% CI = −0.0686; 0.907), meaning a 41.9 percentage point greater probability of surviving five years after diagnosis for ALL patients treated in specialized pediatric hemato-oncology settings. Our results suggest that ALL patients around the threshold could benefit from increased collaboration between pediatric and adult hemato-oncology in terms of survival.

Innovative Approaches to the Management of Acute Lymphoblastic Leukemia Across the Age Spectrum

Adults compose nearly half of all patients diagnosed with acute lymphoblastic leukemia (ALL) and historically have had poor survival compared with pediatric patients. Recently approved therapies, such as monoclonal antibodies, CAR T-cell constructs, and next-generation tyrosine kinase inhibitors, have improved survival in relapsed and refractory ALL, and studies are now examining incorporating these treatments and others into the upfront setting. In adolescent and young adult patients, use of pediatric-based regimens has already improved survival compared with historical controls, and the addition of monoclonal antibodies, such as inotuzumab ozogamicin and blinatumomab, may further enhance this survival benefit. In older adults, approaches have centered on minimizing conventional chemotherapy to decrease toxicity by incorporating monoclonal antibodies and other novel therapies to increase efficacy. With the addition of tyrosine kinase inhibitors to chemotherapy for patients with Philadelphia chromosome-positive ALL, survival of this once poor-prognosis ALL subtype now approaches or exceeds outcomes of other subtypes of adult ALL. Further refinements in the backbone treatment regimen and optimal consolidation approaches will likely improve survival further. Although allogeneic hematopoietic stem cell transplant was previously routinely used as consolidation for adults with ALL, incorporation of measurable residual disease and other risk stratification strategies has enabled better identification of patients who will benefit from allogeneic hematopoietic stem cell transplant. Ongoing clinical trials investigating these approaches will continue the evolution of treatment approaches for adults with ALL, with further improvement in outcomes anticipated.

Controversies in the Treatment of Adolescents and Young Adults with Philadelphia Chromosome-Negative B-Cell Acute Lymphoblastic Leukemia

PURPOSE OF THE REVIEW

The incidence of acute lymphoblastic leukemia (ALL) has been increasing steadily in the adolescent and young adult (AYA) population. In this review article focused on the management of AYAs with Philadelphia chromosome-negative (Ph-) B-ALL, we examine topics of clinical interest and identify areas of controversy in need of further investigation.

RECENT FINDINGS

We explore four areas of active investigation: pediatric-inspired front-line treatment regimens, the optimal time of measurable residual disease (MRD) assessment, the role of hematopoietic stem cell transplant and the optimal salvage therapy for relapsed/refractory B-ALL in AYAs. There has been rapid advancement in the management of ALL in the AYA patient population, which has resulted in improved outcomes. We must build on the successes by continuing to promote multi-center innovative clinical research with clinical trial populations reflecting the AYA ALL patient spectrum. The incorporation of novel targeted immunotherapy into front-line treatment will be transformative and redefine treatment paradigms in the coming years.

Allogeneic transplant compared to pediatric-inspired therapy for Philadelphia chromosome-negative adolescent and adult ALL in first complete remission

BACKGROUND

Pediatric-inspired non-transplant regimens for adolescent and adult ALL patients are becoming standard in many institutions. We aimed to compare a cohort of patients receiving a pediatric-inspired protocol to a cohort of patients treated with adult type ALL therapy followed by allografting after achieving CR1.

METHOD

Eighty-five adolescent and adult ALL patients treated with CALGB 19802 protocol who received MSD transplant in CR1 were retrospectively compared to a matched cohort of 72 adolescent and adult ALL patients treated with a modified version of Children's Cancer Group (CCG) 1900 protocol.

RESULTS

The five years OS in the allo-HCT cohort was 63.1% compared to 80.2% in the pediatric-inspired chemotherapy arm (P = 0.03). The five years EFS in the allo-HCT arm was 58.8% compared to 61.6% in the pediatric-inspired chemotherapy arm (P = 0.07). The five years DFS in the allo-HCT arm was 58.8% as compared to 71.9% in the pediatric-inspired chemotherapy arm (P = 0.07). The relapse rate in the allo-HCT cohort was 30.58% compared to 21.68% in the pediatric-inspired chemotherapy arm (P = 0.16). The NRM in the allo-HCT cohort was 10.59 as compared to 6.45 in the pediatric-inspired chemotherapy arm (P = 0.3).

CONCLUSION

For adolescent and adult patients with Ph-negative ALL, pediatric-inspired chemotherapy resulted in higher OS compared to allo-HCT.

Why Do Children with Acute Lymphoblastic Leukemia Fare Better Than Adults?

It is a new and exciting time for acute lymphoblastic leukemia (ALL). While nearly 50 years ago, only one in nine children with ALL survived with chemotherapy, nowadays nearly 90% of children have a chance of long-term survival. Adults with ALL, as well as the special category of adolescents and young adult (AYA) patients, are catching up with the new developments seen in children, but still their prognosis is much worse. A plethora of factors are regarded as responsible for the differences in treatment response, such as age, ethnicity, disease biology, treatment regimens and toxicities, drug tolerance and resistance, minimal residual disease evaluation, hematopoietic stem cell transplantation timing and socio-economic factors. Taking these factors into account, bringing pediatric-like protocols to adult patient management and incorporating new agents into frontline treatment could be the key to improve the survival rates in adults and AYA.

Optimal treatment for Philadelphia-negative acute lymphoblastic leukemia in first remission in the era of high-intensity chemotherapy

The optimal treatment for Philadelphia chromosome (Ph)-negative acute lymphoblastic leukemia (ALL) in first complete remission (CR1) has not been established in the high-intensity chemotherapy era. The outcomes of patients with Ph-negative ALL who underwent allogeneic hematopoietic stem cell transplantation (HSCT) from a human leukocyte antigen-matched related or unrelated donor in CR1 (HSCT-MRD group and HSCT-MUD group) were obtained from a Japanese registry database. Patients aged 16-24 years and 25-65 years were analyzed separately, and their outcomes were compared to those of patients who continued high-intensity chemotherapy in CR1 in studies (202U group and 202O group) by the Japan Adult Leukemia Study Group (JALSG). In the HSCT-MRD group, patients younger than 25 years had lower overall survival (OS) than the 202U group, presumably due to the higher non-relapse mortality (NRM) in the HSCT-MRD group. Patients 25 years and older had similar OS to the 202O group. The lower relapse rate was counterbalanced by higher NRM in the HSCT-MRD group. In the HSCT-MUD group, patients in both age groups had similar OS to their corresponding groups in the JALSG studies. In conclusion, high-intensity chemotherapy may change the role of HSCT for Ph-negative ALL.

Outcome of young adult patients with very-high-risk acute lymphoblastic leukemia treated with pediatric-type chemotherapy - a single institute experience

BACKGROUND/PURPOSE

Adult patients of acute lymphoblastic leukemia (ALL) with very high-risk (VHR) characteristics have an inferior outcome, and allogeneic hematopoietic stem cell transplantation (HSCT) is usually performed. In contrast, VHR pediatric patients can be treated effectively with minimal residual disease (MRD)-guided pediatric protocols and HSCT are not always needed.

METHODS

We retrospectively reviewed young adult ALL VHR patients treated with the pediatric-type (TPOG-ALL-2002 VHR) regimen in our institute from 2008 to 2019 and compared the event-free survival (EFS) with patients treated with an adult-type regimen (Hyper-CVAD alternating with high dose methotrexate and cytarabine).

RESULTS

We identified 16 patients treated with the TPOG and 11 treated with the Hyper-CVAD regimen. Philadelphia chromosome-positive (n = 10) and T-cell immunophenotype (n = 11) are the most common VHR features. Compared with the Hyper-CVAD group, patients treated with the TPOG regimen showed a trend toward better EFS with a hazard ratio (HR) of 0.42 (p = 0.16). Compared with untransplanted patients, HSCT showed a positive trend in the Hyper-CVAD (HR 0.22, p = 0.12) but not in the TPOG group (p = 0.37). Untransplanted patients treated initially with the hyper-CVAD regimen had a significantly worse outcome than the TPOG regimen (HR 4.19, p < 0.05). In the TPOG group, patients with negative MRD at the end of consolidation had a significantly better outcome (HR 0.12, p = 0.03).

CONCLUSION

Young adult VHR patients can be effectively treated with the TPOG-ALL-2002 protocol, and those who achieved MRD negativity before the end of consolidation have a good outcome without allogeneic HSCT.

Indications for Allogeneic HCT in Adults with Acute Lymphoblastic Leukemia in First Complete Remission

OPINION STATEMENT

Acute lymphoblastic leukemia (ALL) in adults is associated with poor outcomes as compared to children when treated with chemotherapy, leading to a considerably inferior cure rate. Historically, consolidation with allogeneic hematopoietic cell transplant (alloHCT) was routinely recommended for eligible adults with ALL in first complete remission (CR1) if a donor was available, since randomized studies showed superiority over continuing chemotherapy. With the increasing use of pediatric-inspired frontline regimens in young adults with ALL and the availability of novel salvage agents for relapsed/refractory B-cell ALL that have high potential in inducing a second CR, the role of early alloHCT in the treatment paradigm for ALL needs to be reevaluated, and the decision should be individualized for each patient. Simultaneously, alloHCT has evolved considerably lately, and historical randomized studies that have proven the benefit of alloHCT in adults with ALL in CR1 did not included the increasing use of reduced intensity conditioning and haploidentical transplants, and therefore, data may not entirely apply. Nowadays, detectable minimal residual disease (MRD) is the most prognostic determinant of ALL outcome and should be a major consideration in the decision to perform alloHcT in CR1. Nonetheless, other biological and clinical factors remain relevant and can support the complex decision-making. Such factors include high-risk leukemia genetics, the type of administered chemotherapy regimen and the ability of the patient to tolerate all key components of the regimen, and the availability of effective salvage therapies that allow alloHCT to be performed in CR2 in case of relapse after chemotherapy.

MRD-Based Therapeutic Decisions in Genetically Defined Subsets of Adolescents and Young Adult Philadelphia-Negative ALL

Simple Summary

In acute lymphoblastic leukemia (ALL), once a complete remission is achieved following induction chemotherapy, the study of submicroscopic minimal residual disease (MRD) represents a highly sensitive tool to assess the efficacy of early chemotherapy courses and predict outcome. Because of the significant therapeutic progress occurred in adolescent and young adult (AYA) ALL, the importance of MRD in this peculiar age setting has grown considerably, to refine individual prognostic scores within different genetic subsets and support specific risk and MRD-oriented programs. The evidence coming from the most recent MRD-based studies and the new therapeutic directions for AYA ALL are critically reviewed according to ALL subset and risk category.

Abstract

In many clinical studies published over the past 20 years, adolescents and young adults (AYA) with Philadelphia chromosome negative acute lymphoblastic leukemia (Ph− ALL) were considered as a rather homogeneous clinico-prognostic group of patients suitable to receive intensive pediatric-like regimens with an improved outcome compared with the use of traditional adult ALL protocols. The AYA group was defined in most studies by an age range of 18–40 years, with some exceptions (up to 45 years). The experience collected in pediatric ALL with the study of post-induction minimal residual disease (MRD) was rapidly duplicated in AYA ALL, making MRD a widely accepted key factor for risk stratification and risk-oriented therapy with or without allogeneic stem cell transplantation and experimental new drugs for patients with MRD detectable after highly intensive chemotherapy. This combined strategy has resulted in long-term survival rates of AYA patients of 60–80%. The present review examines the evidence for MRD-guided therapies in AYA’s Ph− ALL, provides a critical appraisal of current treatment pitfalls and illustrates the ways of achieving further therapeutic improvement according to the massive knowledge recently generated in the field of ALL biology and MRD/risk/subset-specific therapy

Allogeneic hematopoietic cell transplant overcomes the poor prognostic value of CDKN2 deletion in adult B-lineage acute lymphoblastic leukemia

Emerging evidence suggested that CDKN2 deletion was a poor prognosis predictor in adult B-lineage acute lymphoblastic leukemia (B-ALL). Here, we investigated the effect of allogeneic hematopoietic cell transplant (allo-HCT) on adult B-ALL with CDKN2 deletion. The patients with adult B-ALL underwent more than two courses of chemotherapy were enrolled in the multicenter retrospective study. Relapse and survival were analyzed. A total of 1336 adult B-ALL, including 295 patients with CDKN2 deletion and 1041 wild-type (WT), from five institutes were enrolled. The complete remission (CR) rates were 86.8% and 91.1% (P = 0.229) after two cycles of chemotherapy in patients with CDKN2 deletion and WT, respectively. The 5-year cumulative relapse post-CR were 56% (95% CI, 52-68) and 43% (95% CI, 40-51) (P < 0.001), 5-year disease-free survival (DFS) were 30% (95% CI, 24-36) and 41% (95% CI, 39-46) (P < 0.001), and 5-year overall survival (OS) were 35% (95% CI, 28-39) and 47% (95% CI, 44-49) (P < 0.001) in the two groups, respectively. Subgroup analysis revealed that the 5-year relapse were 89.3% (95% CI, 83.0-96.5) and 68.4% (95% CI, 60.2-72.5) (P < 0.001), 5-year DFS were 4.9% (95% CI, 1.8-10.4) and 22.7% (95% CI, 18.0-27.7) (P < 0.001), and 5-year OS were 6.9% (95% CI, 3.1-12.9) and 23.4% (95% CI, 18.7-28.6) (P < 0.001) in CDKN2 deletion and WT groups undergoing chemotherapy alone, respectively, while there were not different in terms of 5-year relapse (38.1% vs 34.3%, P = 0.211), DFS (48.4% vs 52.2%, P = 0.325) and OS (54.5% vs 56.3%, P = 0.483) between those with CDKN2 deletion and WT undergoing allo-HCT. Multivariate analysis showed that CDKN2 deletion and high-risk stratification both were the risk factors for relapse, DFS and OS, while allo-HCT was a protective factor. CDKN2 deletion might be a poor prognostic predictor of adult B-ALL. Adult B-ALL with CDKN2 deletion might benefit from allo-HCT.

Superior survival with pediatric-style chemotherapy compared to myeloablative allogeneic hematopoietic cell transplantation in older adolescents and young adults with Ph-negative acute lymphoblastic leukemia in first complete remission: analysis from CALGB 10403 and the CIBMTR

Optimal post-remission therapy for adolescents and young adults (AYAs) with Ph-negative acute lymphoblastic leukemia (ALL) in first complete remission (CR1) is not established. We compared overall survival (OS), disease-free survival (DFS), relapse, and non-relapse mortality (NRM) for patients receiving post-remission therapy on CALGB 10403 to a cohort undergoing myeloablative (MA) allogeneic hematopoietic cell transplantation (HCT) in CR1. In univariate analysis, OS was superior with chemotherapy compared to MA allogeneic HCT (3-year OS 77% vs. 53%, P < 0.001). In multivariate analysis, allogeneic HCT showed inferior OS (HR 2.00, 95% CI 1.5–2.66, P < 0.001), inferior DFS (HR 1.62, 95% CI 1.25–2.12, P < 0.001), and increased NRM (HR 5.41, 95% CI 3.23–9.06, P < 0.001) compared to chemotherapy. A higher 5-year relapse incidence was seen with chemotherapy compared to allogeneic HCT (34% vs. 23%, P = 0.011). Obesity was independently associated with inferior OS (HR 2.17, 95% CI 1.63–2.89, P < 0.001), inferior DFS (HR 1.97, 95% CI 1.51–2.57, P < 0.001), increased relapse (1.84, 95% CI 1.31–2.59, P < 0.001), and increased NRM (HR 2.10, 95% CI 1.37–3.23, P < 0.001). For AYA ALL patients in CR1, post-remission therapy with pediatric-style chemotherapy is superior to MA allogeneic HCT for OS, DFS, and NRM.

Measurable Residual Disease Assessment and Allogeneic Transplantation as Consolidation Therapy in Adult Acute Lymphoblastic Leukemia in Colombia

INTRODUCTION

Detectable minimal residual disease (MRD) after therapy for acute lymphoblastic leukemia (ALL) is the strongest predictor of hematologic relapse. The objective of the study was to assess disease-free survival (DFS) and overall survival (OS) of patients with ALL according with MRD status at the end of induction therapy in a Colombian population.

PATIENTS AND METHODS

We assessed a retrospective cohort to compare DFS and OS in adults with de novo ALL according to MRD status at the end of induction chemotherapy, and the type of postinduction consolidation strategy used.

RESULTS

A total of 165 adults with ALL were included in the MRD part of the study, 73 patients in the MRD-negative group and 92 in the MRD-positive group. Median DFS for the MRD-positive group was 11 months (95% confidence interval, 11.7-22.2) and was not reached for the MRD-negative group (P < .001). At 3 years, DFS was 18% and 55%, respectively (P < .001). The median OS for MRD-positive patients was 16 months (95% confidence interval, 8.8-23.15) and was not reached in the MRD-negative group. At 3 years, OS was 26% and 51% for the former and latter group, respectively. Among subjects who did not receive a transplant, median DFS was 21 months for MRD-negative patients and 9 months for MRD-positive patients (P < .001). The median DFS was not reached in either group, whereas 3-year DFS was 64% for MRD-negative and 70% for MRD-positive patients who underwent transplantation in first remission (P = .861).

CONCLUSION

MRD status at the end of induction is an independent prognostic factor for DFS and OS in adult ALL. Allogeneic transplantation in first remission could overcome the adverse prognostic impact of MRD.

Optimal approach to the treatment of young adults with acute lymphoblastic leukemia in 2020

Akin to the introduction of tyrosine kinase inhibitors to Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL), pediatric-based asparaginase-heavy approaches have revolutionized the treatment of young adults with the Philadelphia chromosome-negative subset the past decades. Once again, we are approaching a new era. An era of precision medicine with immunotherapy and other molecularly targeted treatments that offers unique opportunities to customize treatment intensity with or without hematopoietic stem cell transplantation, reduce the burden of toxicities, and combat persistent residual disease. Recently approved agents for refractory/relapsed B-cell precursor ALL include the chimeric antigen receptor-modified T-cells, the anti-CD22 monoclonal antibody-drug conjugate, inotuzumab ozogamicin, and the bispecific anti-CD19 T-cell engager, blinatumomab. These agents are expected to move widely into the frontline setting along with the proteasome inhibitors, bortezomib and carfilzomib, as well as tyrosine kinase inhibitors for Philadelphia-like rearrangements that are especially frequent among young adults. To this add the BH3 mimetics, venetoclax and navitoclax, which are being widely explored in refractory/relapsed as well as frontline settings for B- and T-cell ALL. The promising anti-CD38 monoclonal antibody, daratumumab, is entering the scene of refractory/relapsed T-ALL, whereas the old purine analogue, nelarabine, is being evaluated in a new upfront setting. This review focuses on 2 main questions: How do we optimize frontline as well as salvage ALL treatment of young adults in the 2020s? Not least, how do we address the current burden of serious toxicities unique to young adults?

Optimal therapy for adolescents and young adults with acute lymphoblastic leukemia-current perspectives

Adolescents and young adults (AYA) with acute lymphoblastic leukemia (ALL) have worse prognosis than children. Differing biology of ALL may account for some of this disparity in outcome, with AYA patients having far lower incidence of good risk cytogenetic abnormalities, and higher proportion of patients with genetic lesions associated with inferior survival such as Ph-like ALL. Actual chemotherapy may also contribute to differences in outcome. Retrospective studies have shown that AYA patients treated on pediatric-based regimens had higher survival than those treated with adult regimens; the superiority of pediatric protocols has also been proven in several prospective comparative trials. Increase in rate of enrollment of AYA patients in clinical trials may further improve outcome. Cure based on chemotherapy may further limit the role of allogeneic hematopoietic cell transplantation (HCT) in AYA patients. The unique biology of AYA ALL may allow for novel methods of targeted therapy, while immunotherapy, the efficacy of which has been proven for both children and adults, may also play a major role in the treatment of relapsed/refractory ALL.

Role of Allogeneic HCT as Postremission Therapy for Transplant-Eligible Adult Lymphoblastic Leukemia/Lymphoma After Frontline Hyper-CVAD

BACKGROUND

Hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with cytarabine and methotrexate (hyper-CVAD) is a commonly used regimen in adults with acute lymphoblastic leukemia (ALL)/lymphoblastic lymphoma (LBL). Adult patients fit for pediatric-inspired protocols have an excellent outcome with chemotherapy alone. However, it is unclear whether patients receiving hyper-CVAD should undergo allogeneic hematopoietic cell transplantation (HCT) as postremission therapy. Our aim was to examine the role of HCT at first complete remission (CR1) in adult ALL/LBL after hyper-CVAD.

PATIENTS AND METHODS

Adult patients with newly diagnosed ALL/LBL receiving frontline hyper-CVAD from 2008 to 2018 were identified and records retrospectively extracted.

RESULTS

A total of 85 patients were identified and included for further analysis. The median (range) age was 23 (14-68) years, and 56 (66%) were male. A total of 24 (28%) had adverse cytogenetics, and 48 (56%) had at least one risk factor. All patients received hyper-CVAD as induction; induction failure was seen in 10 (12%). A total of 38 patients continued the hyper-CVAD course, while the remaining 47 received HCT in CR1. Three-year event-free survival (EFS) and overall survival for the entire cohort were 51.4% and 61.6%, respectively. Median follow-up of alive patients was 39.9 (3.8-123.8) months. At multivariable analysis for EFS, induction failure was associated with worse outcome (hazard ratio [HR], 4.8; 95% confidence interval [CI] 1.7-13.7; P = .003), whereas HCT in CR1 improved outcome (HR, 0.42; 95% CI 0.18-0.97; P = .044). Furthermore, HCT in CR1 was the only prognostic factor for overall survival (HR, 0.3; 95% CI 0.11-0.85; P = .023).

CONCLUSION

HCT at CR1 resulted in a favorable EFS and overall survival in ALL/LBL patients after hyper-CVAD frontline therapy. Given that hyper-CVAD is a widely used protocol for adult patients, further examination of this observation is warranted.

Hematopoietic Cell Transplantation for Philadelphia Chromosome Negative Adult Acute Lymphoblastic Leukemia in the Modern Era of Immune Therapy

PURPOSE OF REVIEW

This review will discuss the data and controversies related to HCT in the front-line and relapsed/refractory setting in the context of newly available targeted immunotherapies.

RECENT FINDINGS

Recent studies in adult Ph-negative ALL support the use of measurable residual disease (MRD) response to front-line therapy to guide consolidation. As such, most MRD-negative patients do not require front-line HCT. Blinatumomab benefits patients with B-ALL with MRD+ complete response (CR) and can be used as a bridge to HCT; whether HCT is still required in this setting is an area of ongoing inquiry. Blinatumomab and inotuzumab result in high rates of MRD negative CR in adults with relapsed/refractory ALL and allow more patients with relapsed disease to receive HCT. Chimeric antigen receptor T cell (CAR-T) therapies may serve as a bridge to HCT or as a stand-alone therapy for relapsed/refractory patients; data suggests there may be greater benefit to consolidating CAR-T with HCT in HCT-naïve adults. The decision to incorporate consolidative allogeneic HCT into front-line therapy should be primarily guided by MRD status and the ALL regimen utilized. Targeted immunotherapies result in high MRD-negative CR rates, allowing more adults with relapsed/refractory ALL to be successfully bridged to HCT; early incorporation of these therapies may also prove valuable in reducing the need for HCT in the front-line setting by increasing MRD negative CR rates.

Philadelphia Chromosome-Negative B-Cell Acute Lymphoblastic Leukemia in Adolescents and Young Adults

Adolescents and young adults (AYAs) with Philadelphia chromosome-negative acute lymphoblastic leukemia (ALL) represent a unique patient population with a disproportionate survival disadvantage compared with younger children. Substantial progress has been made as we began to understand and address the multifaceted drivers behind this outcome disparity. New insights into the biology of B-cell ALL have uncovered distinct genetic characteristics more commonly found in AYAs that affect prognosis. Dramatic improvements in survival have been achieved with the use of pediatric-inspired protocols in the front-line setting, as well as antibody-based and chimeric antigen receptor T-cell therapies in the relapsed and refractory setting. Guided by the incorporation of minimal residual disease testing to inform clinical decision making, these represent major paradigm shifts in management. Efforts to design clinical trials geared toward AYAs and to enroll AYAs in available clinical trials will ensure ongoing progress. Holistic care of AYAs with ALL further involves recognition of psychosocial issues arising as a consequence of their diagnosis and the delivery of age-appropriate supportive care.

A pediatric regimen for adolescents and young adults with Philadelphia chromosome-negative acute lymphoblastic leukemia: Results of the ALLRE08 PETHEMA trial

Background

Pediatric‐based or ‐inspired trials have improved the prognosis of adolescents and young adults (AYA) with Philadelphia chromosome‐negative (Ph‐neg) acute lymphoblastic leukemia (ALL).

Methods

This study reports the results of treatment of the ALLRE08 trial, a full pediatric trial for AYA aged 15‐30 years with standard‐risk (SR) ALL.

Results

From 2008 to 2018, 89 patients (38 adolescents [15‐18 years] and 51 young adults [YA, 19‐30 years], median age: 20 [15‐29] years) were enrolled in the ALLRE08 trial. The complete response (CR) was 95%. Twenty‐two patients were transferred to a high‐risk (HR) protocol because of poor marrow response on day 14 (n = 20) or high‐level of end‐induction minimal residual response (MRD ≥ 0.25%, n = 2). Cumulative incidence of relapse (CIR) at 5 years was 35% (95%CI: 23%‐47%), with significant differences between adolescents and YA: 13% (4%‐28%) vs 52% (34%‐67%), P = .012. No treatment‐related mortality was observed in 66/66 patients following the ALLRE08 trial vs 3/23 patients moved to a HR trial. The estimated 5‐year overall survival (OS) was 74% (95%CI: 63%‐85%), with significantly higher rates for adolescents vs YA: 87% (95%CI: 74%‐100%) vs 63% (46%‐80%), P = .021. Although CIR or OS were lower in patients who were transferred to a HR trial, the differences were not statistically significant (CIR: 34% [21%‐47%] vs 37% [14%‐61%]; OS: 78% [66%‐90%] vs 61% [31%;91%]).

Conclusion

A full pediatric trial is feasible and effective for AYA with Ph‐neg, SR‐ALL, with better results for adolescents than for YA. Outcome of patients with poor early response rescued with a HR trial was not significantly inferior.

Practical guidance for the management of acute lymphoblastic leukemia in the adolescent and young adult population

The outstanding therapeutic progress achieved with modern pediatric regimens in childhood acute lymphoblastic leukemia (ALL) led efforts to explore whether a similar treatment approach could be equally effective and safe in older patients, starting initially with older adolescents and young adults (AYA), variably defined in different studies by an age between 15–18 and 25–39 years. Several comparative and noncomparative trials of this type have been carried out during the last two decades, enrolling thousands of patients. Almost without exception, the new strategy improved patients’ outcomes compared with traditional adult treatments in B-lineage and T-lineage Philadelphia (Ph) chromosome-negative B-ALL, while the use of tyrosine kinase inhibitors (TKI) led to comparative progress in Ph+ ALL, a former high-risk subset more typically observed in older age groups. At present, highly effective pediatric-based regimens warrant 5-year survival rates of 60–70% in AYA patients. In view of these data, the same approach was progressively extended to older patients, improving the results up to 55 years of age. Issues of treatment compliance and drug-related toxicity have thus far prevented a comparable therapeutic advancement in patients aged >55 years. This critical review updates and summarizes with pertinent examples this global, positive therapeutic change, and examines how to promote further progress with new targeted therapies that include novel immuno-therapeutics and other agents developed against the many molecular dysfunctions detectable in various ALL subsets. Substantial progress is expected to occur soon, bringing AYA survival figures very close to that of children, and also to improve the outcome of ALL at all ages.

Hematopoietic Cell Transplantation in the Treatment of Adult Acute Lymphoblastic Leukemia: Updated 2019 Evidence-Based Review from the American Society for Transplantation and Cellular Therapy

The role of hematopoietic cell transplantation (HCT) in adults with acute lymphoblastic leukemia (ALL) is reviewed and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published literature and for grading the quality and strength of the evidence and the strength of the recommendations. A panel of ALL experts developed consensus on the treatment recommendations based on the evidence. Allogeneic HCT offers a survival benefit in selected patients with ALL, and this review summarizes the standard indications as well as the areas of controversy. There is now greater experience with pediatric-inspired chemotherapy regimens that has transformed upfront therapy for adult ALL, resulting in higher remission rates and overall survival. This in turn has increased the equipoise around decision making for ALL in first complete remission (CR1) when there is no measurable residual disease (MRD) at the end of induction and/or consolidation. Randomized studies are needed for adults with ALL to compare allogeneic HCT in CR1 with pediatric-inspired chemotherapy alone. Indications for transplantation in the evolving landscape of MRD assessments and novel targeted and immune therapeutics remain important areas of investigation.

Hematopoietic Cell Transplantation in Young Adult Acute Lymphoblastic Leukemia: A United States Population-Level Analysis

In this population-based evaluation of adolescents and young adults (AYA) acute lymphoblastic leukemia (ALL), we describe patterns of care (POC) and outcomes regarding hematopoietic cell transplantation (HCT) in first complete remission (CR1). Data were abstracted from the 2013 United States Surveillance, Epidemiology, and End Results POC study; newly diagnosed AYA ALL were included. Multivariable logistic regression evaluated associations with HCT in CR1; Cox proportional hazards regression evaluated survival associations. Of 399 AYAs with ALL included, 102 (28.5%) underwent HCT in CR1. High-risk cytogenetics (odds ratio [OR] = 4.86, 95% confidence interval [CI] = 3.02-7.83) and hyper-cyclophosphamide, vincristine, adriamycin, and dexamethasone (CVAD) induction (OR = 1.84, 95% CI = 1.07-3.16) were associated with HCT in CR1. Two-year cumulative incidence of relapse, relapse-free survival (RFS), and overall survival (OS) of the entire cohort were 28.3% (95% CI = 23.4-33.4), 69.3% (95% CI = 63.6-74.3%), and 84.1% (95% CI = 79.7-87.5), respectively. Two-year RFS was significantly higher in patients receiving CR1 HCT relative to chemotherapy (83.6%, 95% CI = 72.6-90.5% vs. 64.3%, 95% CI = 57.5-70.3), but no difference was seen in 2-year OS (88.9%, 95% CI = 80.8-93.7 vs. 82.5%, 95% CI = 77.2-86.7). Treatment at a nonteaching hospital was independently associated with inferior OS (hazard ratio = 2.15, 95% CI = 1.23-3.76). Although the ALL landscape is changing, these data provide a snapshot of the use and outcomes of HCT for AYA ALL across the United States.

Hematopoietic stem cell transplantation for adults with Philadelphia chromosome-negative acute lymphoblastic leukemia in first remission: a position statement of the European Working Group for Adult Acute Lymphoblastic Leukemia (EWALL) and the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation (EBMT)

Allogeneic hematopoietic stem cell transplantation (HSCT) in first complete remission is a standard of care for adult patients with Philadelphia chromosome (Ph)-negative acute lymphoblastic leukemia (ALL) and high risk of relapse. However, the stratification systems vary among study groups. Inadequate response at the level of minimal residual disease is the most commonly accepted factor indicating the need for alloHSCT. In this consensus paper on behalf of the European Working Group for Adult Acute Lymphoblastic Leukemia and the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation, we summarize available evidence and reflect current clinical practice in major European study groups regarding both indications for HSCT and particular aspects of the procedure including the choice of donor, source of stem cells and conditioning. Finally, we propose recommendations for daily clinical practice as well as for planning of prospective trials.

A pediatric regimen for older adolescents and young adults with acute lymphoblastic leukemia: results of CALGB 10403

Retrospective studies have suggested that older adolescents and young adults (AYAs) with acute lymphoblastic leukemia (ALL) have better survival rates when treated using a pediatric ALL regimen administered by pediatric treatment teams. To address the feasibility and efficacy of using a pediatric treatment regimen for AYA patients with newly diagnosed ALL administered by adult treatment teams, we performed a prospective study, CALGB 10403, with doses and schedule identical to those in the Children's Oncology Group study AALL0232. From 2007 to 2012, 318 patients were enrolled; 295 were eligible and evaluable for response. Median age was 24 years (range, 17-39 years). Use of the pediatric regimen was safe; overall treatment-related mortality was 3%, and there were only 2 postremission deaths. Median event-free survival (EFS) was 78.1 months (95% confidence interval [CI], 41.8 to not reached), more than double the historical control of 30 months (95% CI, 22-38 months); 3-year EFS was 59% (95% CI, 54%-65%). Median overall survival (OS) was not reached. Estimated 3-year OS was 73% (95% CI, 68%-78%). Pretreatment risk factors associated with worse treatment outcomes included obesity and presence of the Philadelphia-like gene expression signature. Use of a pediatric regimen for AYAs with ALL up to age 40 years was feasible and effective, resulting in improved survival rates compared with historical controls. CALGB 10403 can be considered a new treatment standard upon which to build for improving survival for AYAs with ALL. This trial was registered at www.clinicaltrials.gov as #NCT00558519.

Immune cell constitution in bone marrow microenvironment predicts outcome in adult ALL

As novel immunological treatments are gaining a foothold in the treatment of acute lymphoblastic leukemia (ALL), it is elemental to examine ALL immunobiology in more detail. We used multiplexed immunohistochemistry (mIHC) to study the immune contexture in adult precursor B cell ALL bone marrow (BM). In addition, we developed a multivariate risk prediction model that stratified a poor survival group based on clinical parameters and mIHC data. We analyzed BM biopsy samples of ALL patients (n = 52) and healthy controls (n = 14) using mIHC with 30 different immunophenotype markers and computerized image analysis. In ALL BM, the proportions of M1-like macrophages, granzyme B+CD57+CD8+ T cells, and CD27+ T cells were decreased, whereas the proportions of myeloid-derived suppressor cells and M2-like macrophages were increased. Also, the expression of checkpoint molecules PD1 and CTLA4 was elevated. In the multivariate model, age, platelet count, and the proportion of PD1+TIM3+ double-positive CD4+ T cells differentiated a poor survival group. These results were validated by flow cytometry in a separate cohort (n = 31). In conclusion, the immune cell contexture in ALL BM differs from healthy controls. CD4+PD1+TIM3+ T cells were independent predictors of poor outcome in our multivariate risk model, suggesting that PD1 might serve as an attractive immuno-oncological target in B-ALL.

Graft vs host disease impacts overall survival post allogeneic hematopoietic stem cell transplantation for acute lymphoblastic leukemia/lymphoma

AIM

To examine the outcome and prognostic factors for high risk patients with acute lymphoblastic leukemia/lymphoma (ALL/LBL) who underwent allogeneic hematopoietic stem cell transplantation (HCT) at our center during the period of 2010-2017

METHODS

After due institutional review board approval, patients with high risk ALL/LBL post HCT were identified and included. All records were retrospectively collected. Time to event analysis was calculated from the date of HCT until event of interest or last follow up with Kaplan-Meir means. Cox regression model was used for multivariable analysis calculation.

RESULTS

A total of 69 patients were enrolled and examined with a median age of 21 (14-61). After a median follow up of 15 mo (2-87.3), the 2-year cumulative incidence of relapse, cumulative incidence of non-relapse mortality, progression free survival and overall survival (OS) were 34.1%, 10.9%, 54.9% and 62.8%, respectively. In a multivariable analysis for OS; acute graft vs host disease (GVHD) and chronic GVHD were significant with corresponding hazard ratio 4.9 (1.99-12; P = 0.0007) and 0.29 (0.1-0.67; P = 0.0044), respectively.

CONCLUSION

Allogeneic-HCT for high risk ALL/LBL resulted in promising remissions particularly for patients with cGVHD.

Treatment of young adults with Philadelphia-negative acute lymphoblastic leukemia and lymphoblastic lymphoma: Hyper-CVAD vs. pediatric-inspired regimens

For young adults with acute lymphoblastic leukemia, pediatric-based regimens are likely to provide the following when compared to hyper-CVAD regimens: better disease control, less hospitalization time, diminished acute toxicities, decreased financial cost, more quality-adjusted life years, and fewer adverse late effects, such as infertility, myelodysplasia, and second malignant neoplasms. There are also reasons to expect less cardiac and cognitive dysfunction after pediatric regimens. The improved quality and quantity of life associated with pediatric regimens renders them preferable to hyper-CVAD regimens for the treatment of Philadelphia-negative B-precursor or T-cell acute lymphoblastic leukemia and lymphoblastic lymphoma in young adults.

Minimal Residual Disease Assessment and Risk-based Therapy in Acute Lymphoblastic Leukemia

The study of minimal residual disease (MRD) in adult patients with acute lymphoblastic leukemia (ALL) allows a greater refinement of the individual risk classification and is the best support for risk-specific therapy with or without allogeneic hematopoietic cell transplantation (HCT). Using case-specific sensitive molecular probes or multiparametric flow cytometry on marrow samples obtained from the end of induction until midconsolidation, MRD assays can detect up to 1 leukemic cell of 10,000 total mononuclear cells (sensitivity, 0.01%; ie, ≥10⁴). This cutoff, presently bound to technical limitations and subject to improvement, reflects the individual chemosensitivity and is strongly correlated with treatment outcome. The chance for cure is approximately 70% in the MRD-negative subset but only 20% to 30% in MRD-positive patients, in any diagnostic and risk subset. As shown by prospective trials from Germany, Italy, Spain, and France-Switzerland-Belgium, approximately 50% to 70% of unselected adult patients with Philadelphia-negative ALL achieve and maintain an early MRD response, whereas the remainder do not, including a substantial proportion of clinically standard-risk patients, and require an HCT to avert at least partially the risk of relapse. Along with the diffusion of more effective "pediatric-inspired" chemotherapy programs, the MRD analysis is an integral part of a modern management strategy, guiding the decision process to transplant or not, in which case nonrelapse mortality using HCT in first remission-still 10% to 20%-is totally abolished. The use of new agents such as monoclonal antibodies, small inhibitors, and chimeric antigen receptor T cells is opening a new era of MRD-directed therapies, that will further increase survival rates.

Hematopoietic stem cell transplant in adults with acute lymphoblastic leukemia: the present state

INTRODUCTION

Allogeneic hematopoietic stem cell transplant (allo-HSCT) has an important role in management of acute lymphoblastic leukemia (ALL). Proper patient selection is central to ensure optimal outcomes. Areas covered: This review covers various aspects of HSCT in ALL patients, including indications, donor selection, conditioning regimens, and post-transplant management. Expert commentary: Allo-HSCT is important in post-remission management of ALL but proper risk-stratification is a major challenge. Incorporation of minimal residual disease (MRD) and molecular testing will improve patient allocation. Patients receiving pediatric-inspired induction who achieve molecular remission might not need allo-HSCT in first remission. Allo-HSCT should be considered in patients who don't achieve MDR negativity, didn't receive intensive induction, or have high risk cytogenetic and molecular features. Despite improved responses with tyrosine kinase inhibitors (TKIs) in Philadelphia positive (Ph+) ALL, allo-HSCT remains standard. Matched sibling donors are the optimal graft source, but other sources are valid alternatives. There is no single optimal conditioning regimen and retrospective studies found myeloablative and reduced intensity regimens to be comparable. Following allo-HSCT, there is no role for maintenance therapy in Philadelphia-negative ALL. In Ph+ ALL, maintenance TKIs improve outcomes. The integration of targeted and immunotherapies in the peri-transplant period holds potential for improved outcomes.

Patients over 40 years old with precursor T-cell lymphoblastic lymphoma have different prognostic factors comparing to the youngers

This study aimed to analyze the clinical characteristics and prognostic factors of patients, divided into over 40-year-old group or not, with precursor T-cell lymphoblastic lymphoma (Pre-T-LBL). Based on the retrospective analysis of the clinical data of 59 patients with Pre-T-LBL during the period from December 2010 to December 2015, albumin level, anemia, pleural or pericardial effusion, protocol, therapy response, mediastinal mass, lactate dehydrogenase (LDH), and international prognostic index (IPI) or age-adjusted international prognostic index (aaIPI) were summarized. For patients aged <40 years, factors correlating with poor progression-free survival (PFS) were pleural or pericardial effusion, regimen, albumin level and therapy response. Pleural or pericardial effusion, aaIPI score, regimen, LDH increased, albumin level, therapy response and mediastinal mass were all related with poor overall survival (OS). In the patients aged ≥40 years, only anemia associated with PFS. However, anemia, involvement of bone marrow and therapeutic response were all related with poor OS. In conclusion, the patients with Pre-T-LBL are characterized by a low incidence and bad prognosis. Different prognostic factors can be discovered for patients over 40-year-old with Pre-T-LBL comparing to the youngers. New prognostic evaluation factors should be explored for patients ≥40 years old.

Pretransplant Consolidation Is Not Beneficial for Adults with ALL Undergoing Myeloablative Allogeneic Transplantation

Allogeneic hematopoietic cell transplantation (alloHCT) is curative for patients with acute lymphoblastic leukemia (ALL) who achieve complete remission (CR1) with chemotherapy. However, the benefit of consolidation chemotherapy remains uncertain in patients undergoing alloHCT. We compared clinical outcomes of 524 adult patients with ALL in CR1 who received ≥2 (n = 109), 1 (n = 93), or 0 cycles (n = 322) of consolidation before myeloablative alloHCT from 2008 to 2012. As expected, time to alloHCT was longer with increasing cycles of consolidation. Patients receiving ≥2, 1, or 0 cycles of consolidation had an adjusted 3-year cumulative incidence of relapse of 20%, 27%, and 22%; 1-year transplant-related mortality (TRM) of 16%, 18%, and 23%; adjusted 3-year leukemia-free survival (LFS) of 54%, 48%, and 47%; and 3-year overall survival (OS) of 63%, 59%, and 54% (all P values >.40). Multivariable analysis confirmed that consolidation was not prognostic for LFS (relative risk, 1.20, 95% confidence interval, .86 to 1.67; P = .28 for no consolidation; RR, 1.18, 95% confidence interval, .79 to 1.76; P = .41 for 1 cycle versus ≥2 cycles = reference). Similarly, consolidation was not associated with OS, relapse, TRM, or graft-versus-host disease. We conclude that consolidation chemotherapy does not appear to provide added benefit in adult ALL patients with available donors who undergo myeloablative alloHCT in CR1.