Adult patients with acute lymphoblastic leukemia and molecular failure display a poor prognosis and are candidates for stem cell transplantation and targeted therapies

Allogeneic Hematopoietic Stem Cell Transplantation for Elderly Acute Lymphoblastic Leukemia Patients: A Registry Study From the Société Francophone de Greffe de Moelle et Thérapie Cellulaire (SFGM-TC)

There are very limited data regarding the outcomes of elderly patients with acute lymphoblastic leukemia (ALL) who undergo allogeneic hematopoietic stem cell transplantation (alloHSCT). A total of 316 ALL patients aged ≥ 60 years who underwent alloHSCT between 2010 to 2022 were identified in the SFGM-TC registry. The primary objective was to evaluate progression-free survival (PFS), non-relapse mortality (NRM), relapse incidence (RI), and graft-versus-host disease (GvHD)-free relapse-free survival (GRFS), as well as their risk factors. The median age was 63.8 years (range 60-75.8), 49.8% of patients had Philadelphia-positive B-ALL (Ph + ALL), and 70.9% were in first complete remission (CR1) at transplantation. The donor was an unrelated donor in 52.1%, a matched related donor (MRD) in 26.3%, and a haplo-identical donor in 17.7%. Reduced-intensity conditioning (RIC) was administered to 64.6% of patients, while total body irradiation (TBI) was used in 35.8%. The 3-year overall survival (OS) was 46% (95% CI 40%-53%). The 3-year PFS, NRM, RI, and GRFS were 41% (95% CI 35%-48%), 23% (95% CI 18%-28%), 36% (95% CI 31%-42%), and 30% (95% CI 25%-37%), respectively. Multivariable analyses confirmed poorer OS and PFS in patients with advanced disease, with an HR of 1.79 (95% CI 1.22-2.64), p = 0.0032. Additionally, the ALL subtype significantly impacted outcomes, with an HR of 1.99 (95% CI 1.42-2.79) for non-Ph + ALL. This study suggests that alloHSCT is a viable option for elderly ALL patients, as age itself did not impact outcomes. However, advanced disease and non-Ph + ALL were associated with significantly worse survival.

Inotuzumab Ozogamicin as First-Line Therapy in Acute Lymphoblastic Leukemia

The long-term outcome of older patients with acute lymphoblastic leukemia (ALL) is poor due to a reduced ability to tolerate intensive chemotherapy, a more aggressive disease biology, and the presence of comorbidities. Older adults with Philadelphia chromosome-negative (Ph-) B-cell ALL have the highest rates of treatment failure and complications, and the pediatric-inspired regimens that are effective in younger adults are severely limited by their toxicity in older patients. Targeted therapies, including inotuzumab ozogamicin (InO) and blinatumomab, have potent activity in B-cell ALL and are used today as single agents, and in combination with chemotherapy in both salvage and frontline ALL therapy. Optimized frontline use of B-cell targeting agents would potentially reduce the need for, and exposure to, conventional chemotherapy and improve the tolerance and efficacy of reduced-intensity chemotherapy regimens combined with targeted therapies. This review summarizes the efficacy and safety results of several recent trials investigating different approaches with InO as first-line therapy in patients with Ph- B-cell ALL.

Refining Risk Stratification for B-cell Precursor Adult Acute Lymphoblastic Leukemia Treated With a Pediatric-inspired Regimen by Combining IKZF1 Deletion and Minimal Residual Disease

INTRODUCTION

Minimal residual disease (MRD) is the most important prognostic factor for B-cell acute lymphoblastic leukemia (B-ALL) however nearly 20-30% of patients relapsed even when they achieved negative MRD, how to identify these patients is less addressed. In this study, we aimed to reassess the prognostic significance of MRD and IKZF1 in adult B-ALL patients receiving pediatric chemotherapy regimens.

METHODOLOGY

A total of 202 newly diagnosed adult patients with B-ALL treated at Nanfang Hospital between January 2016 and September 2020 were enrolled in the population-based protocol of the PDT-ALL-2016 trial (NCT03564470), a GRAALL-backbone, peg-aspargase-intensified, antimetabolite-based pediatric-inspired regimen therapy. The validation dataset COG-P9906, which includes complete gene expression profiles and clinical data for 190 samples, is accessible via the NCBI Gene Expression Omnibus (GEO) at the following link: (https://www.ncbi.nlm.nih.gov/geo/), under the accession code GSE11877.

MAIN FINDINGS

B-ALL patients were redefined as standard (MRD-negative and IKZF1wild-type), intermediate (MRD-positive or IKZF1 deletion), and high-risk (MRD-positive and IKZF1 deletion) groups by combining IKZF1 deletion status and MRD. In the PDT-ALL-2016 cohort, patients in the high- and intermediate-risk groups who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) exhibited significantly improved 5-year overall survival (OS), event-free survival (EFS), and lower cumulative incidence of relapse (CIR) compared to those who received chemotherapy alone. In the PDT-ALL-2016 cohort, no significant advantage was observed in the 5-year OS, EFS, and CIR of patients in the standard-risk group who received allo-HSCT compared to those who received chemotherapy.

DISCUSSION

Traditional risk factors, incorporating clinical and cytogenetic features, have been previously evaluated to stratify risks and guide treatment decisions. However, the prognostic strength of this stratified system is limited by the pediatric-inspired protocol background, making it difficult to identify patients with a high risk of relapse. Therefore, in the era of pediatric-inspired protocols, it is imperative to reassess traditional risk factors to identify patients at high risk of recurrence and mortality.In this study, we retrospectively evaluated the combination of MRD and IKZF1 to develop an efficient risk stratification tool for adult patients with B-ALL in the pediatric-inspired chemotherapy era. Moreover, allo-HSCT had distinct efficacy at different risk levels, which means that the decision to perform allo-HSCT may be well guided by this risk classification scheme.

CONCLUSION

In conclusion, based on our cohort study and validation cohort, we demonstrated that the combination of MRD and IKZF1 deletion allows for better risk stratification of adults with B-ALL and that allo-HSCT mitigates the poor prognosis of MRD+ and/or IKZF1del subgroups.

Importance of measurable residual disease in the outcome of adults with acute lymphoblastic leukemia after allogeneic stem cell transplantation: Long follow-up analysis from a single transplant center

INTRODUCTION

In this retrospective study, with prolonged follow-up, we analyze the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in adult acute lymphoblastic leukemia (ALL) and the impact of pre-transplantation measurable residual disease (pre-HSCT MRD).

METHODS

Detection of MRD was performed by multiparametric flow cytometry (MFC) for Philadelphia chromosome-negative ALL (Ph-neg ALL) and by classic genetic tests for Ph-pos ALL.

RESULTS

Among 46 patients in first complete remission (CR1) who had available MRD data, 1- and 3-year cumulative incidences of relapse (CIR) for patients with positive and negative MRD were 47.1% and 52.9% vs. 3.4% and 6.9%, respectively (p<0.001). Disease free survival (DFS) at 1 and 3 years was 82.8% (95% CI 70.1-97.7) and 79.3% (95% CI 65.9-95.5) in the negative MRD group and 35.3% (95% CI 18.5-67.2) and 29.4% (95% CI 14.1-61.4) in the positive MRD group (p<0.001). With a median follow up of 29 months in the entire cohort and 177.6 months (14.8 years) in survivors, 1- and 3-year overall survival (OS) for the pre-HSCT negative MRD group was 82.8% (95% CI 70.1-97.7) and 79.2% (95% CI 65.6-95.5), respectively, compared to 64.7% (95% CI 45.5-91.9) and 41.2% (95% CI 23.3-72.7) in the positive MRD group (p=0.001). In a multivariate model, positive pre-HSCT MRD is associated with increased CIR and poorer DFS and OS.

CONCLUSION

These results support that pre-HSCT MRD should be eradicated to improve survival of adult ALL patients who undergo allo-HSCT.

Advances in Therapy of Adult Patients with Acute Lymphoblastic Leukemia

The landscape of adult acute lymphoblastic leukemia (ALL) is dramatically changing. With very promising results seen with novel immunotherapeutics in the setting of relapsed and refractory disease, the prospect of using these agents in first-line therapy has prompted the development of multiple clinical trials addressing this question. This review seeks to outline and expand the current standard of care, as well as new advances, in the treatment of adult patients with ALL and address future areas of research. We expect the frontline integration of immuno-oncology agents such as bispecific T-cell engagers, antibody-drug conjugates, and chimeric antigen receptor (CAR) T cells may maintain or improve outcomes in adults while also minimizing toxicity. Treatment of ALL will continue to evolve as we focus on personalized, patient-centered approaches.

Venetoclax plus low-intensity chemotherapy for adults with acute lymphoblastic leukemia

ABSTRACT

In acute lymphoblastic leukemia (ALL), the B-cell lymphoma 2 inhibitor venetoclax may enhance the efficacy of chemotherapy, allowing dose reductions. This phase 1b study of venetoclax plus attenuated chemotherapy enrolled 19 patients with ALL either newly diagnosed (aged ≥60 years, n = 11 [B-cell, n = 8; T-cell, n = 3]) or relapsed/refractory (R/R; aged ≥18 years, n = 8 [B-cell, n = 3; T-cell, n = 5]). Venetoclax was given for 21 days with each cycle of mini-hyper-CVD (mini-HCVD; cyclophosphamide, vincristine, dexamethasone alternating with methotrexate and cytarabine). There were no dose-limiting toxicities at dose level 1 (DL1; n = 3, 400 mg/d) or DL2 (n = 6, 600 mg/d); DL2 was the recommended phase 2 dose and explored further (n = 10). The most common nonhematologic adverse events were grade ≥3 infections. There were no deaths within 60 days. There was no tumor lysis syndrome, hepatotoxicity, prolonged cytopenias, or early discontinuation for toxicity. Among patients with newly diagnosed ALL, 10 of 11 (90.9%) achieved a measurable residual disease-negative (<0.01% sensitivity) complete remission (CR) including 6 patients with hypodiploid TP53-mutated ALL. All patients in CR bridged to hematopoietic stem cell transplant (n = 9) or completed protocol (n = 1). With a median follow-up of 60 months, median disease-free survival (DFS) for patients with newly diagnosed ALL was 54.6 months (95% confidence interval [CI], 35.5 to not available), with a 2-year DFS rate of 90% (95% CI, 71-100). Among patients with R/R ALL, 3 of 8 (37.5%) achieved CR. In summary, for patients with newly diagnosed ALL, venetoclax plus mini-HCVD is well tolerated with promising efficacy. This trial was registered at www.clinicaltrials.gov as #NCT03319901.

Allogeneic Hemopoietic Cell Transplantation as a Paradigm for Cellular Immunotherapy

BACKGROUND

Allogeneic hematopoietic cell transplantation (alloHCT) is an established curative treatment for hematological malignancies and other severe blood disorders. However, alloHCT is also known for its significant side effects.

SUMMARY

Here we review recent advances in targeted molecular therapy, immunotherapy, infectiology, and diagnostics that have enhanced the tolerability and efficacy of alloHCT, expanding its use to less fit and elderly patients. We analyze developments in conditioning regimens, donor selection, and the management of graft versus host disease (GVHD) and infections and discuss posttransplantation strategies to prevent relapse.

KEY MESSAGE

In a fresh perspective, alloHCT can serve as a platform to enhance the potential of emerging targeted and immune therapies.

Clinical Utility of a Novel Triplex Digital PCR Assay for Clone Monitoring in Sequential and Relapsed Pediatric B-Cell Acute Lymphoblastic Leukemia Patients

INTRODUCTION

Digital polymerase chain reaction (PCR) studies for clonal disease monitoring in B-acute lymphoblastic leukemia patients are currently limited due to the heterogeneous nature of mutations, which limit cost-effective assay designs.

MATERIALS AND METHODS

In this study, 70 samples (14 relapse and 56 sequential therapy samples) were tested for 13 recurrent mutations identified on deep sequencing in our published cohort (KRAS, NRAS, NT5C2, PMS2, UHRF1, KMT2D, and TP53 genes) via a novel triplex digital PCR assay.

RESULTS AND DISCUSSION

A total of seven major clones of NRAS [five] and NT5C2 [two] were noted in six out of 14 (43%) relapse patients, accounting for 44% of early relapses. In addition, 10 minor clones (PMS2 [two], NRAS [four], NT5C2 [three], and TP53 [one]) were noted in five out of 14 (36%) patients. In the 56 sequential therapy samples, six major clones were noted (NRAS [five], KRAS [one]) in four out of 14 (28.5%) patients, with two increasing in size in maintenance samples, leading to subsequent relapse in both cases. In addition, therapy-acquired minor clones in NT5C2 [four] and PMS2 [one] were seen to emerge in maintenance samples in four out of 14 (28.5%) patients, with concordant detection of such major and minor clones in unpaired relapse samples, indicating the need for their active surveillance during therapy. Overall, digital PCR validated NRAS and NT5C2 major clones in one-third (10 out of 27; 37%) of cases, driving nearly half of early relapses.

How I treat older patients with Ph/BCR-ABL-negative acute lymphoblastic leukemia

ABSTRACT

Despite advancements in new treatments, management of older patients with acute lymphoblastic leukemia (ALL) remains an unmet medical need. With increasing age, patients with ALL have a significantly lower complete remission rate, higher early mortality and relapse rate, and poorer survival than younger patients. This is attributed to a higher prevalence of adverse prognostic factors among older individuals and reduced tolerance to chemotherapy. Progress has been made in tailoring moderately intensive chemotherapy protocols for Philadelphia chromosome (Ph)/BCR::ABL-negative ALL in older patients, and recent phase 2 studies have explored integrating immunotherapy into initial treatment with very promising results. However, establishing new standard regimens for this age group remains and improving general management strategy is a pending task.

Comparable Results Between 8 and 12 Gray TBI in Combination With Fludarabine and Post-Transplant Cyclophosphamide in MRD-Negative but Not in MRD-Positive Acute Lymphoblastic Leukemia Patients Transplanted in First Complete Remission

BACKGROUND

The optimal TBI dose for ALL patients undergoing allogeneic SCT is still not clearly defined.

METHODS

Single-center retrospective analysis of high-risk ALL patients in CR1 treated with 8 Gy (n = 22) or 12 Gy (n = 50) TBI in combination with fludarabine and PTCy. Median patient age in the 8 Gy TBI cohort was 63 (37-79) and 37 (18-56) in the 12 Gy TBI cohort and median follow-up time was 21 months (range 1-92).

RESULTS

OS and LFS at 2 years after 8 Gy were 65% and 55% versus 74% and 74% after 12 Gy (p = 0.3 and p = 0.2, respectively). CIR and NRM at 2 years were 27% and 14% after 8 Gy versus 4% and 20% after 12 Gy (p = 0.004 and p = 0.4, respectively). MRD-positive (+) patients (n = 26) receiving 12 Gy (n = 19) showed better OS (p = 0.01), LFS (p = 0.009), GRFS, lower CIR (p = 0.02), and similar NRM than did MRD+ patients receiving 8 Gy (n = 7). MRD-negative (-) patients (n = 38) receiving 12 Gy (n = 27) had similar OS, LFS, GRFS, lower CIR, and higher NRM (p = 0.04) than did MRD- patients receiving 8 Gy (n = 11).

CONCLUSION

Our study demonstrates that 8 Gy TBI in comparison to 12 Gy TBI results in low NRM but a high relapse rate with similar OS, LFS, and GRFS. In MRD+ high-risk ALL patients, allogeneic SCT with 12 Gy TBI leads to improved OS, LFS, GRFS, and a low relapse rate. Prospective studies comparing the different treatment regimens with larger MRD patient cohorts are needed to confirm this data.

Ph- ALL: immunotherapy in upfront treatment

Antibody-based and cell-based novel immunotherapies, such as bispecific T-cell engagers (BiTE), antibody-drug conjugates, or chimeric antigen receptor (CAR) T cells are currently standard treatment options for patients with relapsed or refractory (R/R) B-cell precursor acute lymphoblastic leukemia (ALL). To date, CD20-targeting monoclonal antibodies and the CD19-targeting BiTE's blinatumomab have been established elements of frontline therapy, either in patients with CD20+ ALL or in patients with measurable disease (MRD) following conventional chemotherapy. Recently, blinatumomab has also demonstrated a survival benefit in patients with MRD-negative ALL. Based on the observed high response rates and improved survival outcomes in patients with R/R ALL, antibody-based immunotherapies are being prospectively studied in the upfront setting, particularly in older adult patients, where even age-adapted conventional chemotherapies are still associated with significant rates of early death, treatment-related toxicity, and poor prognosis. In these approaches, conventional chemotherapy has been replaced or reduced and supplemented by immunotherapeutic agents, resulting in promising outcomes that form the basis for evaluating and defining new treatment standards.

Laboratory validation and clinical utility of next-generation sequencing-based IGH/TCR clonality testing for the monitoring of measurable residual disease in acute lymphoblastic leukaemia: real-world experience at Austin Pathology

Measurable residual disease (MRD) testing is an essential aspect of disease prognostication in acute lymphoblastic leukaemia (ALL) and informs clinical decisions. The depth of MRD clearance is highly relevant and requires assays with sufficient sensitivity. Austin Pathology is one of the few laboratories in Australia currently utilising a fully validated and National Association of Testing Authorities (NATA)-accredited ultrasensitive next-generation sequencing (NGS) platform for MRD monitoring in ALL. This technology is based on the detection of clonal rearrangement of immunoglobulin and T cell receptor genes in leukaemic cells, and is capable of achieving a limit of detection at least one to two logs below that of multiparametric flow cytometry (MFC). In this retrospective analysis, we report a clonotype detection rate of up to 85.7% at diagnosis, and a concordance rate of 78.7% in MRD results between NGS and MFC. Of the discordant samples, nearly all were NGS+/MFC-, highlighting the superior sensitivity of NGS. The enhanced sensitivity is clinically relevant, as discordant MRD results often heralded fulminant relapse, and therefore offer clinicians additional lead time and a window of opportunity to initiate pre-emptive therapy. Notwithstanding a small and heterogeneous cohort, our real-world survival data indicate an intermediate relapse risk for NGS+/MFC- patients. In light of recent approval of Medicare rebatable ALL MRD testing, we discuss how NGS can complement other techniques such as MFC in personalising management strategies. We recommend routine clonality testing by NGS at diagnosis and use a multi-modality approach for subsequent MRD monitoring.

Predicting relapse in acute lymphoblastic leukemia

Outcomes in adult and pediatric patients with acute lymphoblastic leukemia (ALL) have improved over successive generations due to rigorously conducted clinical trials and incorporation of novel therapeutic agents. Despite these advances, approximately 20% of high-risk pediatric patients and 50% of adults with ALL will fail to achieve long-term remission with frontline chemotherapy protocols, mostly due to relapse. The ability to predict which patients with ALL are more likely to relapse allows for early intensification of therapy and/or incorporation of novel immunotherapies with the goal of relapse prevention. In this review, we outline the most robust clinical predictors of relapse in ALL with a focus on measurable residual disease (MRD) and genomics. We also discuss application of these prognostic tools in different clinical settings including frontline treatment, pre-/post-allogeneic stem cell transplant, and pre-/post-Chimeric Antigen Receptor T-cell therapy.

Measurable residual disease (MRD)-testing in haematological cancers: A giant leap forward or sideways?

Measurable residual disease (MRD)-testing is used in many haematological cancers to estimate relapse risk and to direct therapy. Sometimes MRD-test results are used for regulatory approval. However, some people including regulators wrongfully believe results of MRD-testing are highly accurate and of proven efficacy in directing therapy. We review MRD-testing technologies and evaluate the accuracy of MRD-testing for predicting relapse and the strength of evidence supporting efficacy of MRD-guided therapy. We show that at the individual level MRD-test results are often an inaccurate relapse predictor. Also, no convincing data indicate that increasing therapy-intensity based on a positive MRD-test reduces relapse risk or improves survival. We caution against adjusting therapy-intensity based solely on results of MRD-testing.

Comparing transplant outcomes in ALL patients after myeloablative conditioning in mismatch-related or unrelated donor settings

The optimal myeloablative conditioning regimen for ALL patients undergoing hematopoietic cell transplant (HCT) with an alternative donor is unknown. We analyzed HCT outcomes ALL patients (n = 269) who underwent HCT at our center from 2010 to 2020 in complete remission (CR) after FTBI-etoposide and CNI-based GvHD prophylaxis for matched donor HCT (ETOP-package; n = 196) or FTBI-Fludarabine and post-transplant cyclophosphamide (PTCy)-based prophylaxis for HLA- mismatched (related or unrelated) donors (FLU-package; n = 64). Patients in FLU-package showed a significant delay in engraftment (p < 0.001) and lower cumulative incidence (CI) of any and extensive chronic GVHD (p = 0.009 and 0.001, respectively). At the median follow up of 4.6 years (range 1-12 years); non-relapse mortality, overall or leukemia-free survival and GVHD-free/relapse-free survival were not significantly impacted by the choice of conditioning. However, in patients at CR2 or with measurable residual disease (MRD+), there was a trend towards higher relapse after FLU-package (p = 0.08 and p = 0.07, respectively), while patients at CR1 regardless of MRD status had similar outcomes despite the package/donor type (p = 0.9 and 0.7, respectively). Our data suggests that FLU-package for alternative donors offers comparable outcomes to ETOP-package for matched donor HCT to treat ALL. Disease status and depth of remission at HCT were independent predictors for better outcomes.

Center effect on allogeneic hematopoietic stem cell transplantation outcomes for B-cell acute lymphoblastic leukemia

This nationwide study retrospectively examined the center effect on allogeneic hematopoietic stem cell transplantation (allo-HSCT) for adult B-cell acute lymphoblastic leukemia. The cohort analyses were separated into Philadelphia chromosome (Ph)-positive and -negative cases. The patients were divided into low- and high-volume groups according to the number of allo-HSCTs at each facility. The primary endpoint was 5-year overall survival (OS). This study included 1156 low-volume and 1329 high-volume Ph-negative and 855 low-volume and 926 high-volume Ph-positive cases. In Ph-negative cases, 5-year OS was significantly higher in the high-volume centers at 52.7% (95% confidence interval [CI]: 49.9-55.5) versus 46.8% (95% CI: 43.8-49.7) for the low-volume centers (P < 0.01). Multivariate analysis identified high volume as a favorable prognostic factor (hazard ratio [HR]: 0.81 [95% CI: 0.72-0.92], P < 0.01). Subgroup analysis in Ph-negative cases revealed that the center effects were more evident in patients aged ≥40 years (HR: 0.72, 95% CI: 0.61-0.86, P < 0.01) and those receiving cord blood transplantation (HR: 0.62, 95% CI: 0.48-0.79, P < 0.01). In Ph-positive cases, no significant difference was observed between the high and low-volume centers for 5-year OS (59.5% [95% CI: 56.2-62.7] vs. 54.9% [95% CI: 51.3-58.3], P = 0.054). In multivariate analysis, center volume did not emerge as a significant prognostic indicator. This study showed center effects on survival in Ph-negative but not in Ph-positive cases, highlighting the heterogeneity of the center effect in allo-HSCT for B-cell acute lymphoblastic leukemia. Collaborative efforts among transplant centers and further validation are essential to improve outcomes.

Ikaros Deletions among Bulgarian Patients with Acute Lymphoblastic Leukemia/Lymphoma

The Ikaros zinc finger factor 1 is a transcription factor with a well-known role in B- and T-cell development. The deletions of IKZF1 have an established significance in acute lymphoblastic leukemia, while reports on its prevalence and prognostic significance among ALL subtypes and regions vary. Breakpoint-specific qPCR is a practical method for testing of the most frequent types of IKZF1 deletions, considering there is clustering of the deletion events. The most commonly reported deletions are Δ4-7, Δ4-8, Δ2-7, and Δ2-8, with deletion Δ4-7 being the most common one. We retrospectively administered a breakpoint-specific qPCR design for screening for the most frequent types of IKZF1 deletions to 78 ALL patients that were diagnosed and treated between 2010 and 2022. We observed the products through gel electrophoresis, and we conducted descriptive statistics, EFS, and OS analyses. Our study found 19 patients with IKZF1 deletions, with two subjects manifesting more than one deletion. The prevalence in the different subgroups was as follows: Ph/+/ B-ALL 46%, Ph/-/ B-ALL 30%, T-ALL/LBL 4%. There was a statistically significant difference in EFS of 39 vs. 0% in favor of patients without deletions (p = 0.000), which translated to a difference in OS of 49 vs. 0% (p = 0.001). This difference was preserved in the subgroup of Ph/-/ B-ALL, while there was no significant difference in the Ph/+/ B-ALL. The most frequently observed type of deletion (15 out of 19) was the Δ4-7. There is a strong negative prognostic impact of the IKZF1 deletions at diagnosis in the observed population. IKZF1 deletion testing through breakpoint-specific qPCR is a practical approach in diagnostic testing for this risk factor. IKZF1 deletions may warrant treatment decisions and intensified treatment strategies to overcome the negative prognostic impact.

SOHO State of the Art Updates and Next Questions | Novel Agents and the Diminishing Role of Allogeneic Stem Cell Transplant in B-Acute Lymphoblastic Leukemia

Outcomes of patients with B-acute lymphoblastic leukemia (B-ALL) have improved remarkably in the past decade. This has largely been due to the development and introduction of novel immunotherapies such as blinatumomab, inotuzumab ozogamicin, chimeric antigen receptor T (CAR-T) cells, highly potent tyrosine kinase inhibitors, and improved risk stratification, including better understanding of high risk genomic subgroups and better methods of measurable residual disease (MRD) detection. Historically, allogeneic stem cell transplant (allo-SCT) has been the consolidative treatment of choice in first complete remission for fit adults with B-ALL. However, allo-SCT is associated with significant treatment-related mortality and morbidity. Current research is directed at the incorporation of novel immunotherapies into frontline regimens to improve depth and durability of responses and ultimately increase cure rates. In this review, we will discuss the emerging role of novel immune-based treated strategies in both the frontline and relapsed/refractory settings. We present our approach to newly diagnosed patients with B-ALL and illustrate how the incorporation of novel agents and use of high-sensitivity MRD assays can abrogate the need for allo-SCT in most patients with B-ALL.

Allogeneic stem cell transplant with TBI-based myeloablative conditioning in adolescents and young adults with Philadelphia chromosome-negative ALL treated with pediatric protocols

To investigate the safety of total body irradiation-based myeloablative conditioning (TBI-MAC) in adolescent and young adult (AYA) Philadelphia chromosome (Ph)-negative acute lymphoblastic leukemia (ALL) patients treated with pediatric protocols, treatment outcomes of 106 AYA patients aged 16-39 years old undergoing allogeneic stem cell transplant (allo-SCT) with TBI-MAC in the first remission were compared according to chemotherapy types before transplant. Pediatric and adult protocols were used in 56 and 50 of the patients, respectively. The cumulative incidence (CI) of non-relapse mortality (NRM) and the overall survival (OS) rates were not significantly different between the pediatric-protocol and adult-protocol group (NRM: 4 % vs. 14 % at five years post-transplant, respectively, p = 0.26; OS: 81 % vs. 66 %, respectively, p = 0.14). Multivariate analysis for NRM revealed that a performance status >0 (hazard ratio [HR] = 4.8) and transplant due to chemotherapy toxicities (HR = 3.5) were independent risk factors, but a pediatric protocol was not (HR = 0.48). The CI of NRM and the OS rates were also similar among patients aged over 24 years old. These findings suggested that conventional allo-SCT with TBI-MAC can be performed without increasing NRM in AYA patients with Ph-negative ALL even after pediatric protocols.

Measurable residual disease testing by next generation sequencing is more accurate compared with multiparameter flow cytometry in adults with B-cell acute lymphoblastic leukemia

Results of measurable residual disease (MRD)-testing by next-generation sequencing (NGS) correlate with relapse risk in adults with B-cell acute lymphoblastic leukemia (ALL) receiving chemotherapy or an allotransplant from a human leukocyte antigen (HLA)-identical relative or HLA-matched unrelated donor. We studied cumulative incidence of relapse (CIR) and survival prediction accuracy using a NGS-based MRD-assay targeting immunoglobulin genes after 2 courses of consolidation chemotherapy cycles in 93 adults with B-cell ALL most receiving HLA-haplotype-matched related transplants. Prediction accuracy was compared with MRD-testing using multi-parameter flow cytometry (MPFC). NGS-based MRD-testing detected residual leukemia in 28 of 65 subjects with a negative MPFC-based MRD-test. In Cox regression multi-variable analyses subjects with a positive NGS-based MRD-test had a higher 3-year CIR (Hazard Ratio [HR] = 3.37; 95 % Confidence Interval [CI], 1.34-8.5; P = 0.01) and worse survival (HR = 4.87 [1.53-15.53]; P = 0.007). Some data suggest a lower CIR and better survival in NGS-MRD-test-positive transplant recipients but allocation to transplant was not random. Our data indicate MRD-testing by NGS is more accurate compared with testing by MPFC in adults with B-cell ALL in predicting CIR and survival. (Registered in the Beijing Municipal Health Bureau Registration N 2007-1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTROPC-14005546]).

Need for consensus on primary end points and efficacy definitions in trials for adult acute lymphoblastic leukemia

ABSTRACT

The lack of consensus on acceptable primary end points and definitions of response and survival in phase 2/3 efficacy studies for adult acute lymphoblastic leukemia has led to widely different clinical trial designs. Inconsistency in primary end point selection and lack of consensus on response, survival end points, and adequate follow-up time lead to difficulty in interpreting completed studies and developing future trials. The lack of consensus also runs the risk of integrating ineffective or unacceptably toxic regimens into clinical practice and future trials. Increasingly, studies integrating highly active, targeted agents into chemotherapy use short-term end points of response, measurable residual disease-negative response, and early event-free survival without confidence that these end points will translate into improved late patient outcomes. This article highlights the current consequences and dilemmas caused by this lack of consensus. The hope is to stimulate discussion and ultimately consensus to improve the interpretation and application of clinical trial results.

Advances in the treatment of Philadelphia chromosome negative acute lymphoblastic leukemia

There have been major paradigm shifts in the treatment of Philadelphia chromosome negative (Ph-) acute lymphoblastic leukemia (ALL) in the last decade with the introduction of new immunotherapies and targeted agents, adoption of pediatric-type chemotherapy protocols in younger adults as well as chemotherapy light approaches in older adults and the incorporation of measurable residual disease (MRD) testing to inform clinical decision making. With this, treatment outcomes in adult Ph- ALL have improved across all age groups. However, a subset of patients will still develop relapsed disease, which can be challenging to treat and associated with poor outcomes. Here we review the treatment of Ph- ALL in both younger and older adults, including the latest advancements and future directions.

Upfront allogeneic hematopoietic stem cell transplantation for adult T-cell acute lymphoblastic leukemia/lymphoma in first complete remission: a single-center study

BACKGROUND

Real-world data on outcomes of upfront allogeneic hematopoietic stem cell transplantation (allo-HCT) for adult T-cell acute lymphoblastic leukemia/lymphoma (T-ALL) patients in first complete remission (CR1) is still lacking.

METHODS

A single center retrospective study was conducted from 94 consecutive patients received their first allo-HCT between 2010 and 2021, which include 76 patients received upfront allo-HCT and 18 patients received allo-HCT in non-upfront settings.

RESULTS

There were no significant differences in most variables. In the upfront allo-HCT group, 52 (68%) patients achieved CR1 with one cycle of induction regimen. 24 (32%) patients achieved CR1 with more than one cycle. In the non-upfront group, there were 14 patients with active disease and 4 patients in second CR before transplant. The majority of patients received antithymocyte globulin-based graft-versus-host disease prophylaxis. Median follow-up time was 51 months for both groups. 5-year overall survival (OS) was 54% in the upfront allo-HCT group. While, in the non-upfront group, 5-year OS were 19% (P = 0.013). 5-year progression free survival in the upfront group was higher than that in the non-upfront group (50% versus 20%, P = 0.02). 5-year cumulative incidence relapse rate was significantly higher in non-upfront group (64% vs. 32%, P = 0.006). While, there was no difference in the 5-year non-relapse mortality (NRM) rate (19% versus 16%, P = 0.56). The most common cause of death was disease progression. In multivariable analysis, non-upfront allo-HCT (hazard ratios (HR) 2.14, P = 0.03) and HCT-CI (≥ 2) (HR 6.07, P = 0.002) were identified to be associated with worse OS. Non-upfront allo-HCT and HCT-CI (≥ 2) were also found to be independent risk factors for higher relapse rate. While, haploidentical-HCT was found to be associated with increased NRM.

CONCLUSIONS

Our study indicated that allo-HCT remains an important curative treatment for adult patients with T-ALL, especially when it was performed in the upfront setting.

Acute lymphoblastic leukaemia

Acute lymphoblastic leukaemia (ALL) is a haematological malignancy characterized by the uncontrolled proliferation of immature lymphoid cells. Over past decades, significant progress has been made in understanding the biology of ALL, resulting in remarkable improvements in its diagnosis, treatment and monitoring. Since the advent of chemotherapy, ALL has been the platform to test for innovative approaches applicable to cancer in general. For example, the advent of omics medicine has led to a deeper understanding of the molecular and genetic features that underpin ALL. Innovations in genomic profiling techniques have identified specific genetic alterations and mutations that drive ALL, inspiring new therapies. Targeted agents, such as tyrosine kinase inhibitors and immunotherapies, have shown promising results in subgroups of patients while minimizing adverse effects. Furthermore, the development of chimeric antigen receptor T cell therapy represents a breakthrough in ALL treatment, resulting in remarkable responses and potential long-term remissions. Advances are not limited to treatment modalities alone. Measurable residual disease monitoring and ex vivo drug response profiling screening have provided earlier detection of disease relapse and identification of exceptional responders, enabling clinicians to adjust treatment strategies for individual patients. Decades of supportive and prophylactic care have improved the management of treatment-related complications, enhancing the quality of life for patients with ALL.

Molecular subgroups of T-cell acute lymphoblastic leukemia in adults treated according to pediatric-based GMALL protocols

In contrast to B-cell precursor acute lymphoblastic leukemia (ALL), molecular subgroups are less well defined in T-lineage ALL. Comprehensive studies on molecular T-ALL subgroups have been predominantly performed in pediatric ALL patients. Currently, molecular characteristics are rarely considered for risk stratification. Herein, we present a homogenously treated cohort of 230 adult T-ALL patients characterized on transcriptome, and partly on DNA methylation and gene mutation level in correlation with clinical outcome. We identified nine molecular subgroups based on aberrant oncogene expression correlating to four distinct DNA methylation patterns. The subgroup distribution differed from reported pediatric T-ALL cohorts with higher frequencies of prognostic unfavorable subgroups like HOXA or LYL1/LMO2. A small subset (3%) of HOXA adult T-ALL patients revealed restricted expression of posterior HOX genes with aberrant activation of lncRNA HOTTIP. With respect to outcome, TLX1 (n = 44) and NKX2-1 (n = 4) had an exceptionally favorable 3-year overall survival (3y-OS) of 94%. Within thymic T-ALL, the non TLX1 patients had an inferior but still good prognosis. To our knowledge this is the largest cohort of adult T-ALL patients characterized by transcriptome sequencing with meaningful clinical follow-up. Risk classification based on molecular subgroups might emerge and contribute to improvements in outcome.

A Multicentre, Randomized Trial in Adults with de novo Philadelphia Chromosome-Positive Acute Lymphoblastic Leukaemia to Assess the Efficacy of Ponatinib versus Imatinib in Combination with Low-Intensity Chemotherapy, to Compare End of Therapy with Indication for Stem Cell Transplantation versus Tyrosine Kinase Inhibitor, Blinatumomab, and Chemotherapy in Optimal Responders, and to Evaluate Blinatumomab in Suboptimal Responders (GMALL-EVOLVE)

INTRODUCTION

Philadelphia chromosome-positive acute lymphoblastic leukaemia (Ph+ALL) is treated as standard of care (SoC) by imatinib-based treatment combined with induction and consolidation chemotherapy followed by allogeneic stem cell transplantation (SCT) in first remission. The German Multicenter ALL Study Group for Adult ALL (GMALL) reports about a trial to evaluate the impact of ponatinib-based therapy, blinatumomab treatment for suboptimal responders, and the possibility of omission of SoC Allo SCT in optimal responders entitled GMALL-EVOLVE.

METHODS

Herein, imatinib is randomized versus ponatinib as frontline treatment combined with chemotherapy, optimal responders also get randomized between SCT and chemo-immunotherapy, and suboptimal responders receive immunotherapy before SCT. The trial is registered under the EudraCT number 2022-000760-21.

CONCLUSION

This trial will answer several major questions in the treatment of Ph+ALL.

Management of ALL in adults: 2024 ELN recommendations from a European expert panel

ABSTRACT

Experts from the European Leukemia Net (ELN) working group for adult acute lymphoblastic leukemia have identified an unmet need for guidance regarding management of adult acute lymphoblastic leukemia (ALL) from diagnosis to aftercare. The group has previously summarized their recommendations regarding diagnostic approaches, prognostic factors, and assessment of ALL. The current recommendation summarizes clinical management. It covers treatment approaches, including the use of new immunotherapies, application of minimal residual disease for treatment decisions, management of specific subgroups, and challenging treatment situations as well as late effects and supportive care. The recommendation provides guidance for physicians caring for adult patients with ALL which has to be complemented by regional expertise preferably provided by national academic study groups.

Diagnosis, prognostic factors, and assessment of ALL in adults: 2024 ELN recommendations from a European expert panel

ABSTRACT

Working groups of the European LeukemiaNet have published several important consensus guidelines. Acute lymphoblastic leukemia (ALL) has many different clinical and biological subgroups and the knowledge on disease biology and therapeutic options is increasing exponentially. The European Working Group for Adult ALL has therefore summarized the current state of the art and provided comprehensive consensus recommendations for diagnostic approaches, biologic and clinical characterization, prognostic factors, and risk stratification as well as definitions of endpoints and outcomes. Aspects of treatment, management of subgroups and specific situations, aftercare, and supportive care are covered in a separate publication. The present recommendation intends to provide guidance for the initial management of adult patients with ALL and to define principles as a basis for future collaborative research.

Effect of sustained measurable residue disease negativity and post-remission treatment selection on the prognosis of acute lymphoblastic leukemia in adults

BACKGROUND

To explore the effects of monitoring measurable residual disease and post-remission treatment selection on the clinical outcomes of B-cell acute lymphoblastic leukemia (B-ALL) in adults.

METHODS

Between September 2010 and January 2022, adult patients with B-ALL who received combination chemotherapy, with or without allogeneic hematopoietic stem cell transplantation (allo-HSCT), were included in the retrospective study, which was approved by the Ethics Committee and the observation of Declaration of Helsinki conditions.

RESULTS

One hundred and forty-three B-ALL patients achieved complete remission (CR) were included in the study, of whom 94 patients (65.7%) received allo-HSCT in first complete remission (CR1). Multivariate analysis showed that the most powerful factors affecting OS were transplantation (hazard ratio [HR] = 0.540, p = 0.037) and sustained measurable residue disease (MRD) negativity (HR = 0.508, p = 0.037). The subgroup analysis showed that the prognosis of the allo-HSCT group was better than that of the chemotherapy group, regardless of whether MRD was negative or positive after two courses of consolidation therapy. After consolidation therapy, the prognosis of patients with positive MRD remained significantly better in the allo-HSCT group than in the chemotherapy group. However, no significant difference was observed in the prognosis between the allo-HSCT and chemotherapy groups with negative MRD after consolidation therapy.

CONCLUSIONS

B-ALL patients who achieve sustained MRD negativity during consolidation therapy have excellent long-term outcomes even without allo-HSCT. Allo-HSCT is associated with a significant benefit in terms of OS and DFS for patients who were with positive MRD during consolidation therapy.

All about blinatumomab: the bispecific T cell engager immunotherapy for B cell acute lymphoblastic leukemia

INTRODUCTION

B cell acute lymphoblastic leukemia-lymphoma (B-ALL) accounts for approximately 75% of ALL cases and is observed in children and adults. Recent advances in disease diagnosis, stratification and prognostication have led to a better characterization of different subgroups of ALL. Notwithstanding the significant improvement in the complete remission rate of B-ALL, patients with minimal residual disease (MRD) and relapsed/refractory (R/R) settings suffer from poor outcomes.

HYPOTHESIS

However, novel therapies, such as agents targeting tyrosine kinases or the CD20 molecule, combination therapies and improved supportive care, have changed the treatment landscape of B-ALL.

METHOD AND RESULTS

Meanwhile, blinatumomab has been FDA-approved for MRD-positive or R/R B-ALL patients. Blinatumomab is a bispecific T cell engager containing the CD3 and CD19 that recognize domains redirecting cytotoxic T cells to lyse B cells. Promising outcomes, including long-term overall survival and improved MRD-negative response rates, have been reported in patients who received this drug. Adding blinatumomab to new ALL regimens seems promising for achieving better outcomes in poor prognosis B-ALL patients. Nevertheless, the neurotoxicity and cytokine release syndrome are the two major adverse events following the blinatumomab therapy.

CONCLUSION

This review summarizes the function and effectiveness of blinatumomab in R/R and MRD positive B-ALL patients. Furthermore, blinatumomab's positive and negative aspects as a novel therapy for B-ALL patients have been briefly discussed.

Efficacy and Safety in Early application of Ruxolinitib for high-risk: Acute lymphoblastic leukemia to prevent GVHD and recurrence after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been identified as the potentially curative treatment for high-risk acute lymphoblastic leukemia (ALL) in adult patients. However, relapse of the disease and/or development of graft-versus-host disease (GVHD) remain to be the most common barriers for successful allo-HSCT. Preclinical studies showed that ruxolitinib, a Janus tyrosine kinase (Jak)1 and Jak2 inhibitor, has a selective anti-GVHD effects while preserving a potent graft-versus-leukemia (GVL) effect. Our study aimed to investigate the efficacy and safety in early application of ruxolitinib for the high-risk ALL patients to prevent GVHD.

METHODS

There were eight patients undergoing allo-HSCT at the Bone Marrow Transplantation Center of the Third Xiangya Hospital of Central South University between April 2020 and April 2021. Ruxolitinib (5-10 mg twice daily) was administered early (median time: 45 days) after stem cell infusion.

RESULTS

After a median follow-up of 14 months (range from 8 to 18 months), the ALL disease relapse occurred in two cases. Among all eight patients, two of them developed grade I/II acute (a) GVHD, while no patient developed grade III/IV aGVHD, and one patient developed chronic (c) GVHD. As for the virus activation, no patient developed EBV activation or EBV related lymphoproliferative disease, and three patients developed CMV activation. Our results suggest that the early application of ruxolitinib could safely and effectively prevent the occurrence of GVHD after allo-HSCT for the high-risk ALL patients. However, it may have a limited effect on preventing the recurrence of high-risk ALL and thus may require additional therapy with other anti-relapse drugs.

CONCLUSIONS

Our preliminary observations suggest that an early application of ruxolitinib can safely and effectively prevent the occurrence of GVHD after allo-HSCT for the high-risk ALL patients. However, ruxolitinib may have a limited effect on preventing the ALL recurrence of high-risk patients.

A prognostic score system in adult T-cell acute lymphoblastic leukemia after hematopoietic stem cell transplantation

Adult T-cell acute lymphoblastic leukemia (T-ALL) is highly aggressive with poor prognoses, while hematopoietic stem cell transplantation (HSCT) is a curable option. However, no transplant-specific prognostic model for adult T-ALL is available. We identified 301 adult T-ALL patients who received HSCT at our hospital between 2010 and 2022. These patients were randomly assigned at a 7:3 ratio to a derivation group of 210 patients and a validation group of 91 patients. Next, we developed a prognostic risk score system for adult T-ALL with HSCT, which we named COMM, including 4 predictors (central nervous system involvement, Non-CR1 (CR2+ or NR) at HSCT, minimal residual disease (MRD) ≥ 0.01% after first induction therapy, and MRD ≥ 0.01% before HSCT). Patients were categorized into three risk groups, low-risk (0), intermediate-risk (1-4), and high-risk (5-12), and their 3-year overall survival (OS) were 87.5% (95%CI, 78-93%), 65.7% (95%CI, 53-76%) and 20% (95%CI, 10-20%; P < 0.001), respectively. The area under the subject operating characteristic curve for 2-, 3- or 5-year OS in the derivation cohort and in the validation cohort were all greater than 0.75. Based on internal validation, COMM score system proved to be a reliable prognostic model that could discriminate and calibrate well. We expect that the first prognostic model in adults T-ALL after HSCT can provide a reference of prognostic consultation for patients and families, and also contribute to future research to develop risk adapted interventions for high-risk populations.

Concordance of Next-Generation Sequencing and Multiparametric Flow Cytometry Methods for Detecting Measurable Residual Disease in Adult Acute Lymphoblastic Leukemia: Optimizing Prediction of Clinical Outcomes From a Single-Center Study

INTRODUCTION

Detection of measurable residual disease (MRD) in adults with acute lymphoblastic leukemia (ALL) is a vital biomarker in risk prediction and treatment selection. Next-generation sequencing (NGS) offers greater sensitivity relative to multiparametric flow cytometry (MFC) and may be a better predictive tool for identifying ALL patients at risk of relapse.

PATIENTS AND METHODS

This single-center retrospective study compares MRD detection by NGS versus MFC in 52 adult B- and T-ALL patients treated at our institution between 2018 and 2023. Pretreatment bone marrow samples were used for assay calibration, while post-treatment MRD assessment was completed up to 4.5 months after the first complete remission (CR1) using an MRD cutoff of 10-6 for distinguishing relapse risk.

RESULTS

The 2-year cumulative incidence of relapse (CIR) among patients who were MRD positive using MFC and NGS was 39.5% and 46.2%, respectively. Unlike MFC, post-CR1 MRD positivity with NGS significantly predicted CIR (HR = 9.47, P = .028). In patients who were MRD negative by MFC, low levels of MRD detected by NGS distinguished patients at high risk of relapse (HR 10.3, P = .026, 2-year CIR 51.6%).

CONCLUSION

Our data suggests that assessment of post-CR1 MRD using a highly sensitive NGS assay can identify ALL patients undergoing frontline therapy at increased risk of relapse and guide the use of adjuvant therapy.

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.

Inotuzumab Ozogamicin as Induction Therapy for Patients Older Than 55 Years With Philadelphia Chromosome-Negative B-Precursor ALL

PURPOSE

Despite recent advances in adapting the intensity of treatment for older patients with ALL, current protocols are associated with high rates of early deaths, treatment-related toxicity, and dismal prognosis. We evaluated inotuzumab ozogamicin and dexamethasone (Dex) as induction therapy in older patients with ALL within the German Multicenter Study Group for Adult ALL (GMALL).

PATIENTS AND METHODS

The open-label, multicenter, phase II, INITIAL-1 trial enrolled 45 patients older than 55 years with newly diagnosed, CD22-positive, BCR::ABL-negative B-precursor ALL (B-ALL). Patients received up to three cycles of inotuzumab ozogamicin/Dex and up to six cycles of age-adapted GMALL consolidation and maintenance therapy.

RESULTS

Forty-three evaluable patients with common/pre-B (n = 38) and pro-B ALL (n = 5), with a median age of 64 years (range, 56-80), received at least two cycles of inotuzumab ozogamicin induction therapy. All patients achieved complete remission (CR/CR with incomplete hematologic recovery). Twenty-three (53%) and 30 (71%) patients had no evidence of molecularly assessed measurable residual disease (minimum 10e-4 threshold) after the second and third inductions, respectively. After a median follow-up of 2.7 years, event-free survival at one (primary end point) and 3 years was 88% (95% CI, 79 to 98) and 55% (95% CI, 40 to 71), while overall survival (OS) was 91% (95% CI, 82 to 99) and 73% (95% CI, 59 to 87), respectively. None of the patients died during 6 months after the start of induction. Most common adverse events having common toxicity criteria grade ≥3 during induction were leukocytopenia, neutropenia, thrombocytopenia, anemia, and elevated liver enzymes. One patient developed nonfatal veno-occlusive disease after induction II.

CONCLUSION

Inotuzumab ozogamicin-based induction followed by age-adapted chemotherapy was well tolerated and resulted in high rates of remission and OS. These data provide a rationale for integrating inotuzumab ozogamicin into first-line regimens for older patients with B-ALL.

PHF6-altered T-ALL Harbor Epigenetic Repressive Switch at Bivalent Promoters and Respond to 5-Azacitidine and Venetoclax

PURPOSE

To assess the impact of PHF6 alterations on clinical outcome and therapeutical actionability in T-cell acute lymphoblastic leukemia (T-ALL).

EXPERIMENTAL DESIGN

We described PHF6 alterations in an adult cohort of T-ALL from the French trial Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003/2005 and retrospectively analyzed clinical outcomes between PHF6-altered (PHF6ALT) and wild-type patients. We also used EPIC and chromatin immunoprecipitation sequencing data of patient samples to analyze the epigenetic landscape of PHF6ALT T-ALLs. We consecutively evaluated 5-azacitidine efficacy, alone or combined with venetoclax, in PHF6ALT T-ALL.

RESULTS

We show that PHF6 alterations account for 47% of cases in our cohort and demonstrate that PHF6ALT T-ALL presented significantly better clinical outcomes. Integrative analysis of DNA methylation and histone marks shows that PHF6ALT are characterized by DNA hypermethylation and H3K27me3 loss at promoters physiologically bivalent in thymocytes. Using patient-derived xenografts, we show that PHF6ALT T-ALL respond to the 5-azacytidine alone. Finally, synergism with the BCL2-inhibitor venetoclax was demonstrated in refractory/relapsing (R/R) PHF6ALT T-ALL using fresh samples. Importantly, we report three cases of R/R PHF6ALT patients who were successfully treated with this combination.

CONCLUSIONS

Overall, our study supports the use of PHF6 alterations as a biomarker of sensitivity to 5-azacytidine and venetoclax combination in R/R T-ALL.

Diagnostic and therapeutic advances in adults with acute lymphoblastic leukemia in the era of gene analysis and targeted immunotherapy

Acute lymphoblastic leukemia (ALL) is one of the most rapidly changing hematological malignancies with advanced understanding of the genetic landscape, detection methods of minimal residual disease (MRD), and the development of immunotherapeutic agents with good clinical outcomes. The annual incidence of adult ALL in Korea is 300-350 patients per year. The WHO classification of ALL was revised in 2022 to reflect the molecular cytogenetic features and suggest new adverse- risk subgroups, such as Ph-like ALL and ETP-ALL. We continue to use traditional adverse-risk features and cytogenetics, with MRD-directed post-remission therapy including allogeneic hematopoietic cell transplantation. However, with the introduction of novel agents, such as ponatinib, blinatumomab, and inotuzumab ozogamicin incorporated into frontline therapy, good MRD responses have been achieved, and overall survival outcomes are improving. Accordingly, some clinical trials have suggested a possible era of chemotherapy-free or transplantation-free approaches in the near future. Nevertheless, relapse of refractory ALL still occurs, and some poor ALL subtypes, such as Ph-like ALL and ETP-ALL, are unsolved problems for which novel agents and treatment strategies are needed. In this review, we summarize the currently applied diagnostic and therapeutic practices in the era of advanced genetic analysis and targeted immunotherapies in United States and Europe and introduce real-world Korean data.

Genetic alterations and MRD refine risk assessment for KMT2A-rearranged B-cell precursor ALL in adults: a GRAALL study

KMT2A-rearranged (KMT2A-r) B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is widely recognized as a high-risk leukemia in both children and adults. However, there is a paucity of data on adults treated in recent protocols, and the optimal treatment strategy for these patients is still a matter of debate. In this study, we set out to refine the prognosis of adult KMT2A-r BCP-ALL treated with modern chemotherapy regimen and investigate the prognostic impact of comutations and minimal residual disease (MRD). Of 1091 adult patients with Philadelphia-negative BCP-ALL enrolled in 3 consecutive trials from the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL), 141 (12.9%) had KMT2A-r, with 5-year cumulative incidence of relapse (CIR) and overall survival (OS) rates of 40.7% and 53.3%, respectively. Molecular profiling highlighted a low mutational burden in this subtype, reminiscent of infant BCP-ALL. However, the presence of TP53 and/or IKZF1 alterations defined a subset of patients with significantly poorer CIR (69.3% vs 36.2%; P = .001) and OS (28.1% vs 60.7%; P = .006) rates. Next, we analyzed the prognostic implication of MRD measured after induction and first consolidation, using both immunoglobulin (IG) or T-cell receptor (TR) gene rearrangements and KMT2A genomic fusion as markers. In approximately one-third of patients, IG/TR rearrangements were absent or displayed clonal evolution during the disease course, compromising MRD monitoring. In contrast, KMT2A-based MRD was highly reliable and strongly associated with outcome, with early good responders having an excellent outcome (3-year CIR, 7.1%; OS, 92.9%). Altogether, our study reveals striking heterogeneity in outcomes within adults with KMT2A-r BCP-ALL and provides new biomarkers to guide risk-based therapeutic stratification.

Molecular Residual Disease in Breast Cancer: Detection and Therapeutic Interception

Breast cancer remains a leading cause of cancer-related death in women despite screening and therapeutic advances. Early detection allows for resection of local disease; however, patients can develop metastatic recurrences years after curative treatment. There is no reliable blood-based monitoring after curative therapy, and radiographic evaluation for metastatic disease is performed only in response to symptoms. Advances in circulating tumor DNA (ctDNA) assays have allowed for a potential option for blood-based monitoring. The detection of ctDNA in the absence of overt metastasis or recurrent disease indicates molecular evidence of cancer, defined as molecular residual disease (MRD). Multiple studies have shown that MRD detection is strongly associated with disease recurrence, with a lead time prior to clinical evidence of recurrence of many months. Importantly, it is still unclear whether treatment changes in response to ctDNA detection will improve outcomes. There are currently ongoing trials evaluating the efficacy of therapy escalation in the setting of MRD, and these studies are being conducted in all major breast cancer subtypes. Additional therapies under study include CDK4/6 inhibitors, PARP inhibitors, HER2-targeted therapies, and immunotherapy. This review will summarize the underlying scientific principles of various MRD assays, their known prognostic roles in early breast cancer, and the ongoing clinical trials assessing the efficacy of therapy escalation in the setting of MRD.

Clinical significance of end of induction measurable residual disease monitoring in B-cell acute lymphoblastic leukemia: A single center experience

The assessment of measurable residual disease (MRD) has emerged as a powerful prognostic tool for both pediatric and adult acute lymphoblastic leukemia (ALL). This retrospective study aimed to evaluate the prognostic relevance of the end of induction MRD in B-cell acute lymphoblastic leukemia (B ALL) patients. The study included 481 patients who underwent treatment for B ALL between August 2012 and March 2019 and had their MRD at the end of induction assessed by flow cytometry. Baseline demographic characteristics were collected from the patient's clinical records. Event free survival (EFS) and relapse free survival (RFS) were calculated using Kaplan-Meier analysis and survival estimates were compared using the log-rank test. End of induction MRD and baseline karyotype were the strongest predictors of EFS and RFS on multivariate analysis. The EFS was inversely related to the MRD value and the outcomes were similar in patients without morphological remission at the end of induction and patients in remission with MRD ≥1.0%. Even within the subgroups of ALL based on age, karyotype, BCR::ABL1 translocation and the treatment protocol, end of induction MRD positive patients had poor outcomes compared to patients who were MRD negative. The study outcome would help draft end of induction MRD-based treatment guidelines for the management of B ALL patients.

Novel precision medicine approaches and treatment strategies in hematological malignancies

Genetic testing has been applied for decades in clinical routine diagnostics of hematological malignancies to improve disease (sub)classification, prognostication, patient management, and survival. In recent classifications of hematological malignancies, disease subtypes are defined by key recurrent genetic alterations detected by conventional methods (i.e., cytogenetics, fluorescence in situ hybridization, and targeted sequencing). Hematological malignancies were also one of the first disease areas in which targeted therapies were introduced, the prime example being BCR::ABL1 inhibitors, followed by an increasing number of targeted inhibitors hitting the Achilles' heel of each disease, resulting in a clear patient benefit. Owing to the technical advances in high-throughput sequencing, we can now apply broad genomic tests, including comprehensive gene panels or whole-genome and whole-transcriptome sequencing, to identify clinically important diagnostic, prognostic, and predictive markers. In this review, we give examples of how precision diagnostics has been implemented to guide treatment selection and improve survival in myeloid (myelodysplastic syndromes and acute myeloid leukemia) and lymphoid malignancies (acute lymphoblastic leukemia, diffuse large B-cell lymphoma, and chronic lymphocytic leukemia). We discuss the relevance and potential of monitoring measurable residual disease using ultra-sensitive techniques to assess therapy response and detect early relapses. Finally, we bring up the promising avenue of functional precision medicine, combining ex vivo drug screening with various omics technologies, to provide novel treatment options for patients with advanced disease. Although we are only in the beginning of the field of precision hematology, we foresee rapid development with new types of diagnostics and treatment strategies becoming available to the benefit of our patients.

A modified CALGB 10403 in adolescents and young adults with acute lymphoblastic leukemia in Central America

Mexico and Central America have a high incidence of acute lymphoblastic leukemia (ALL) in adolescents and young adults. Historically, this patient group has been treated using adult-based regimens, which entails a high rate of treatment-related mortality and a poor overall survival (OS). The use of the CALGB 10403, a pediatric-inspired regimen, has been proven effective in this patient subgroup. Nonetheless, low- and middle-income countries (LMICs) may present limited access to standard care treatments implemented elsewhere, warranting the need for further research to improve outcomes among vulnerable populations. In this study, we present the outcomes in terms of safety and effectiveness of using a modified CALGB 10403 regimen to reflect drug and resource availability in LMICs. Modifications included the use of Escherichia coli asparaginase,6-mercaptopurine instead of thioguanine and the use of rituximab among patients with CD20+. A total of 95 patients with a median age of 23 (range, 14-49) years treated with this modified scheme were prospectively assessed at 5 centers in Mexico and 1 in Guatemala. Among these, 87.8% achieved a complete response after induction. During follow-up, 28.3% of patients relapsed. Two-year OS rate was 72.1%. Factors associated with worse OS included hyperleukocytosis (hazard ratio [HR], 4.28; 95% confidence interval [CI], 1.81-10.10) and postinduction minimal residual disease (HR, 4.67; 95% CI, 1.75-12.44). Most patients presented hepatotoxicity (51.6% and 53.7% during induction and consolidation, respectively), and the treatment-related mortality was 9.5%. Overall, results highlight that implementing a modified CALGB 10403 regimen in Central America is feasible, and it is associated with improvements in clinical outcomes and a manageable safety profile.

Bispecific Antibodies in Hematological Malignancies: A Scoping Review

Bispecific T-cell engagers (BiTEs) and bispecific antibodies (BiAbs) have revolutionized the treatment landscape of hematological malignancies. By directing T cells towards specific tumor antigens, BiTEs and BiAbs facilitate the T-cell-mediated lysis of neoplastic cells. The success of blinatumomab, a CD19xCD3 BiTE, in acute lymphoblastic leukemia spearheaded the expansive development of BiTEs/BiAbs in the context of hematological neoplasms. Nearly a decade later, numerous BiTEs/BiAbs targeting a range of tumor-associated antigens have transpired in the treatment of multiple myeloma, non-Hodgkin's lymphoma, acute myelogenous leukemia, and acute lymphoblastic leukemia. However, despite their generally favorable safety profiles, particular toxicities such as infections, cytokine release syndrome, myelosuppression, and neurotoxicity after BiAb/BiTE therapy raise valid concerns. Moreover, target antigen loss and the immunosuppressive microenvironment of hematological neoplasms facilitate resistance towards BiTEs/BiAbs. This review aims to highlight the most recent evidence from clinical trials evaluating the safety and efficacy of BiAbs/BiTEs. Additionally, the review will provide mechanistic insights into the limitations of BiAbs whilst outlining practical applications and strategies to overcome these limitations.

The current landscape: Allogeneic hematopoietic stem cell transplant for acute lymphoblastic leukemia

One of the consistent features in development of hematopoietic stem cell transplant (HCT) for Acute Lymphoblastic Leukemia (ALL) is the rapidity with which discoveries in the laboratory are translated into innovations in clinical care. Just a few years after murine studies demonstrated that rescue from radiation induced marrow failure is mediated by cellular not humoral factors, E. Donnall Thomas reported on the transfer of bone marrow cells into irradiated leukemia patients. This was followed quickly by the first descriptions of Graft versus Leukemia (GvL) effect and Graft versus Host Disease (GvHD). Despite the pivotal nature of these findings, early human transplants were uniformly unsuccessful and identified the challenges that continue to thwart transplanters today - leukemic relapse, regimen related toxicity, and GvHD. While originally only an option for young, fit patients with a matched family donor, expansion of the donor pool to include unrelated donors, umbilical cord blood units, and more recently the growing use of haploidentical donors have all made transplant a more accessible therapy for patients with ALL. Novel agents for conditioning, prevention and treatment of GvHD have improved outcomes and investigators continue to develop novel treatment strategies that balance regimen related toxicity with disease control. Our evolving understanding of how to prevent and treat GvHD and how to prevent relapse are incorporated into novel clinical trials that are expected to further improve outcomes. Here we review current considerations and future directions for both adult and pediatric patients undergoing HCT for ALL, including indication for transplant, donor selection, cytoreductive regimens, and outcomes.

Pegaspargase-modified risk-oriented program for adult acute lymphoblastic leukemia: results of the GIMEMA LAL1913 trial

Pediatric-inspired chemotherapy is the standard of care for younger adults with Philadelphia chromosome-negative acute lymphoblastic leukemia/lymphoma (Ph- ALL/LL). In LAL1913 trial, the Gruppo Italiano Malattie EMatologiche dell'Adulto added pegaspargase 2000 IU/m2 to courses 1, 2, 5, and 6 of an 8-block protocol for patients aged from 18 to 65 years, with dose reductions in patients aged >55 years. Responders were risk stratified for allogeneic hematopoietic cell transplantation (HCT) or maintenance per clinical characteristics and minimal residual disease (MRD). Of 203 study patients (median age, 39.8 years), 91% achieved a complete remission. The 3-year overall survival, event-free, and disease-free survival (DFS) rates were 66.7%, 57.7%, and 63.3%, respectively, fulfilling the primary study end point of a 2-year DFS >55%. Although based on the intention-to-treat, the DFS being 74% and 50% in the chemotherapy (n = 94) and HCT (n = 91) assignment cohorts, respectively, a time-dependent analysis proved the value of HCT in patients who were eligible (DFS HCT 70% vs no HCT 26%; P <.0001). In multivariate analysis, age and MRD were independent factors predicting DFS rates of 86% (age ≤ 40 and MRD-negative), 64%-65% (MRD-positive or age > 40) and 25% (age > 40 and MRD-positive); P < .0001. Grade ≥2 pegaspargase toxicity was mainly observed at course 1, contributing to induction death in 2 patients but was rare thereafter. This program improved outcomes of patients with Ph- ALL/LL aged up to 65 years in a multicenter national setting. This trial was registered at www.clinicaltrials.gov as #NCT02067143.

Characteristics of Molecular Genetic Mutations and Their Correlation with Prognosis in Adolescent and Adult Patients with Acute Lymphoblastic Leukemia

INTRODUCTION

The prognosis of acute lymphoblastic leukemia (ALL) in adolescents and adults is poor, and recurrence is an important cause of their death. Changes of genetic information play a vital role in the pathogenesis and recurrence of ALL; however, the impact of molecular genetic mutations on disease diagnosis and prognosis remains unexplored. This study aimed to explore the frequency spectrum of gene mutations and their prognostic significance, along with the minimal residual disease (MRD) level and hematopoietic stem cell transplantation (HSCT), in adolescent and adult patients aged ≥15 years with ALL.

METHODS

The basic characteristics, cytogenetics, molecular genetics, MRD level, treatment regimen, and survival outcome of patients with untreated ALL (≥15 years) were collected, and the correlation and survival analysis were performed using the SPSS 25.0 and R software.

RESULTS

This study included 404 patients, of which 147 were selected for next-generation sequencing (NGS). NGS results revealed that 91.2% of the patients had at least one mutation, and 67.35% had multiple (≥2) mutations. NOTCH1, PHF6, RUNX1, PTEN, JAK3, TET2, and JAK1 were the most common mutations in T-ALL, whereas FAT1, TET2, NARS, KMT2D, FLT3, and RELN were the most common mutations in B-ALL. Correlation analysis revealed the mutation patterns, which were significantly different between T-ALL and B-ALL. In the prognostic analysis of 107 patients with B-ALL, multivariate analysis showed that the number of mutations ≥5 was an independent risk factor for overall survival and the RELN mutation was an independent poor prognostic factor for event-free survival.

DISCUSSION

The distribution of gene mutations and the co-occurrence and repulsion of mutant genes in patients with ALL were closely related to the immunophenotype of the patients. The number of mutations ≥5 and the RELN mutation were significantly associated with poor prognosis in adolescent and adult patients with ALL.

Allogeneic stem cell transplant outcomes between TBI-containing reduced intensity and myeloablative conditioning regimens for ALL in complete remission

Total-body irradiation (TBI)-based conditioning regimen is preferred in acute lymphoblastic leukemia (ALL). We retrospectively evaluated allogeneic stem cell transplant (alloSCT) outcomes of 86 adult ALL patients in complete remission (CR) who received TBI-containing reduced intensity (RIC) (Flu/Mel/TBI = 31) and myeloablative conditioning (MAC) (VP16/TBI = 47; CY/TBI = 8) between January 2005 and December 2019. All patients received peripheral blood allografts. Patients in the RIC group were older than the MAC group (61 years old versus 36 years, p < .001). Donor was 8/8 HLA-matched in 83% and unrelated in 65% of patients. Three-year survival was 56.04% for RIC and 69.9% for MAC (HR 0.64; p = .19). Propensity score-based multivariable Cox analyses (PSCA) did not demonstrate any difference in grade III-IV acute graft versus host disease (GVHD) (SHR 1.23, p = .91), chronic GVHD (SHR 0.92, p = .88), survival (HR 0.94, p = .92), and relapse-free survival (HR 0.66, p = .47) between both groups, while relapse rate was lower (SHR 0.21, p = .02) for MAC compared to RIC. Our study did not demonstrate any difference in survival for TBI-containing RIC and MAC alloSCT for adult ALL in CR.

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.