Acute Lymphoblastic Leukemia Therapy Research Articles

Bispecific monoclonal antibody blinatumomab in the first-line therapy of B-lineage acute lymphoblastic leukemia in children and adolescents: interim results of the Russian Ministry of Health approbation protocol

Bispecific monoclonal antibody blinatumomab in the first-line therapy of B-lineage acute lymphoblastic leukemia in children and adolescents: interim results of the Russian Ministry of Health approbation protocol

Impact of tocilizumab on anti-CD19 chimeric antigen receptor T-cell therapy in B-cell acute lymphoblastic leukemia.

Tocilizumab is commonly used for the management of chimeric antigen receptor (CAR) T-cell therapy-associated cytokine release syndrome (CRS). However, it remains unknown whether tocilizumab or its dosage affects the efficacy and safety of CAR T-cell therapy. The objective of this multicenter retrospective study was to explore the impact of tocilizumab on CAR T-cell therapy. In total, 93 patients with B-cell acute lymphoblastic leukemia (B-ALL) receiving humanized anti-CD19 CAR T cells were recruited from May 2016 to November 2022. Forty-five patients received tocilizumab (tocilizumab group), whereas 48 patients did not (nontocilizumab group). Thirteen patients received >1 dose of tocilizumab. The primary end point was the effect of tocilizumab on the efficacy and safety of CAR T cells. Additionally, proliferation, killing, and cytokine assays of CAR T cells were performed in vitro in the presence of tocilizumab. The median age of the patients was 33 years, with 47 males and 46 females. Patients in the tocilizumab group showed similar complete response (CR) rate, overall survival (OS), and event-free survival (EFS) compared with the nontocilizumab group. Compared with patients who received ≤1 dose of tocilizumab, receiving >1 dose of tocilizumab did not affect their CR rate, OS, or EFS. In the tocilizumab group, all patients experienced CRS and 26.7% experienced immuneeffector cell-associated neurotoxicity syndrome (ICANS). In the nontocilizumab group, 64.6% of patients experienced CRS and 8.3% experienced ICANS. Up to 75% of ICANS and 87.5% of grade ≥3 ICANS occurred in the tocilizumab group. In vitro, tocilizumab did not impair the proliferation and killing effects of CAR T cells. Tocilizumab does not affect the efficacy of CAR T cells but may increase the likelihood of ICANS.

Flow cytometric minimal residual disease measurement accounting for cytogenetics in children with non-high-risk acute lymphoblastic leukemia treated according to the ALL-MB 2008 protocol.

Quantitative measurement of minimal residual disease (MRD) is the "gold standard" for estimating the response to therapy in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Nevertheless, the speed of the MRD response differs for different cytogenetic subgroups. Here we present results of MRD measurement in children with BCP-ALL, in terms of genetic subgroups with relation to clinically defined risk groups. A total of 485 children with non-high-risk BCP-ALL with available cytogenetic data and MRD studied at the end-of-induction (EOI) by multicolor flow cytometry (MFC) were included. All patients were treated with standard-risk (SR) of intermediate-risk (ImR) regimens of "ALL-MB 2008" reduced-intensity protocol. Among all study group patients, 203 were found to have low-risk cytogenetics (ETV6::RUNX1 or high hyperdiploidy), while remaining 282 children were classified in intermediate cytogenetic risk group. For the patients with favorable and intermediate risk cytogenetics, the most significant thresholds for MFC-MRD values were different: 0.03% and 0.04% respectively. Nevertheless, the most meaningful thresholds were different for clinically defined SR and ImR groups. For the SR group, irrespective to presence/absence of favorable genetic lesions, MFC-MRD threshold of 0.1% was the most clinically valuable, although for ImR group the most informative thresholds were different in patients from low-(0.03%) and intermediate (0.01%) cytogenetic risk groups. Our data show that combining clinical risk factors with MFC-MRD measurement is the most useful tool for risk group stratification of children with BCP-ALL in the reduced-intensity protocols. However, this algorithm can be supplemented with cytogenetic data for part of the ImR group.

Involvement of BCR::ABL1 in laminin adhesion of Philadelphia chromosome-positive acute lymphoblastic leukemia through upregulation of integrin α6.

Adhesion of cancer cells to extracellular matrix laminin through the integrin superfamily reportedly induces drug resistance. Heterodimers of integrin α6 (CD49f) with integrin β1 (CD29) or β4 (CD104) are major functional receptors for laminin. Higher CD49f expression is reportedly associated with a poorer response to induction therapy in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Moreover, a xenograft mouse model transplanted with primary BCP-ALL cells revealed that neutralized antibody against CD49f improved survival after chemotherapy. Considering the poor outcomes in Philadelphia chromosome (Ph)-positive ALL treated with conventional chemotherapy without tyrosine kinase inhibitors, we sought to investigate an involvement of the laminin adhesion. Ph-positive ALL cell lines expressed the highest levels of CD49f among the BCP-ALL cell lines with representative translocations, while CD29 and CD104 were ubiquitously expressed in BCP-ALL cell lines. The association of Ph-positive ALL with high levels of CD49f gene expression was also confirmed in two databases of childhood ALL cohorts. Ph-positive ALL cell lines attached to laminin and their laminin-binding properties were disrupted by blocking antibodies against CD49f and CD29 but not CD104. The cell surface expression of CD49f, but not CD29 and CD104, was downregulated by imatinib treatment in Ph-positive ALL cell lines, but not in their T315I-acquired sublines. Consistently, the laminin-binding properties were disrupted by the imatinib pre-treatment in the Ph-positive ALL cell line, but not in its T315I-acquired subline. BCR::ABL1 plays an essential role in the laminin adhesion of Ph-positive ALL cells through upregulation of CD49f.

Central role of the mTORC1 pathway in glucocorticoid activity against B-ALL cells

Glucocorticoids (GCs), such as dexamethasone and prednisone, are crucial components of B-cell precursor acute lymphoblastic leukemia (B-ALL) therapies. However, the molecular basis of GC-induced cell death remains elusive. Here we show that GC suppresses mTORC1 (mechanistic target of rapamycin complex 1) signaling and that, conversely, oncogenic activation of mTORC1 confers resistance to GC. Our genome-wide CRISPR/Cas9 dropout screens reveal that depletion of components of either the GATOR1 (Gap Activity TOward Rags 1) or TSC (Tuberous Sclerosis Complex) complexes, both negative regulators of mTORC1 signaling, significantly attenuates B-ALL cell sensitivity to dexamethasone. Dexamethasone primarily induces B-ALL cell death by downregulating mTORC1 activity, thus promoting autophagy and impairing protein synthesis. Dexamethasone treatment failed to suppress mTORC1 activity in B-ALL cells expressing mutant glucocorticoid receptors lacking DNA-binding capacity, suggesting that dexamethasone transcriptionally represses mTORC1 activity. RNA-sequencing analysis identified multiple dexamethasone target genes that negatively regulate mTORC1 activity. Our findings suggest that GC sensitivity is significantly influenced by oncogenic stimuli and/or growth factors that activate the PI3K-AKT-mTORC1 pathway. This is consistent with the frequent GC resistance found in Ph and Ph-like ALLs.

[Clinical Characteristics of CD4-CD56+ Blastic Plasmacytoid Dendritic Cell Neoplasm].

To explore the clinical manifestations, pathological features, immunophenotype, as well as diagnosis, treatment and prognosis of patients with CD4-CD56+ blastic plasmacytoid dendritic cell neoplasm (BPDCN), in order to further understand the rare disease. The clinical data, laboratory examinations and treatment regimens of two patients with CD4-CD56+ BPDCN in the First Affiliated Hospital of Wannan Medical College were retrospectively analyzed. The two patients were both elderly males with tumor involved in skin, bone marrow, lymph nodes, etc. Immunohistochemical results of skin lesions showed that both CD56 and CD123 were positive, while CD4, CD34, TdT, CD3, CD20, MPO and EBER were negative. Flow cytometry of bone marrow demonstrated that CD56, CD123, and CD304 were all positive, while specific immune markers of myeloid and lymphoid were negative. Two patients were initially very sensitive to acute lymphoblastic leukemia or lymphomatoid chemotherapy regimens, but prone to rapid relapse. The overall survival of both patients was 36 months and 4 months, respectively. CD4-CD56+ BPDCN is very rare and easily misdiagnosed as other hematological tumors with poor prognosis. Acute lymphoblastic leukemia or lymphomatoid therapy should be used first to improve the poor prognosis.

Abstract 4002: Investigating CAR-T cell efficacy and activation in the disseminated NALM6-luc human B-cell acute lymphoblastic leukemia model

Abstract Introduction: Chimeric Antigen Receptor T (CAR-T) cell therapy has emerged as a promising approach for treating hematological malignancies, particularly B-cell acute lymphoblastic leukemia (B-ALL). This study aimed to delve into the activation dynamics and therapeutic efficacy of CD19 CAR-T cells in a disseminated NALM6-luc human B-ALL murine model. Experimental design: NALM6-Luc-mCh-Puro cells were implanted intravenously in female NSG (NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ) mice. Animals were treated with CD19 CAR-T cells alone and in combination with ibrutinib. The anti-tumor activity was assessed, and the persistence and activation of CAR-T cells in the blood were evaluated using flow cytometry. Additionally, ddPCR analysis was employed to quantify CAR copy numbers, providing insights into the T-cell persistence over time. Results: Treatment with CD19 CAR-T cells exhibited notable anti-cancer activity and that activity was enhanced in combination with ibrutinib, in line with other reports. The increased time to progression was noted as 69.2% for the CAR-T group and 138.4% for the combination of CAR-T and ibrutinib compared to control. Flow cytometry analysis showed that CAR-T cells persisted in the blood throughout the study. The mean CAR-T absolute cell count for both CAR-T and CAR-T plus ibrutinib treated groups increased from 2 cell/µL blood on Day 0 to 11 and 51 cells/µL of blood, respectively, by Day 39. The progressive increase of PD-1+ and LAG-3+ percentage cells correlates positively with tumor burden, indicating a dynamic link between biomarker upregulation and the presence of tumor cells in mice. ddPCR analysis revealed an initial CAR copy decrease in all groups, followed by gradual increase in tumor-bearing mice treated with CD19 CAR-T cells, with a dramatic increase observed by Day 39. Results from CAR-T treated and CAR-T plus ibrutinib treated groups were comparable, showing mean copy numbers per ng of DNA increasing from less than 1 on day 4 to 17.9 and 23.3, respectively, on day 39. Importantly, no changes were noted in non-tumor implanted mice, emphasizing the tumor dependency for CAR-T cell expansion. Conclusion: This study emphasizes the marked anti-cancer activity of CD19 CAR-T cells in the NALM6-Luc-mCh-Puro B-ALL murine model. Comprehensive analysis of CAR-T cell persistence and activation, including insights from ddPCR, provides a robust understanding of therapeutic response dynamics. The observed in vivo anti-cancer efficacy aligns with the persistence of CAR-T cells revealed by flow cytometry and the dynamic expansion captured through ddPCR analysis. Our results indicate ddPCR and flow cytometry as complementary and independent methods for assessing the systemic CAR-T cell persistence, contributing to optimizing therapy for B-cell acute lymphoblastic leukemia. Citation Format: Prashant Pandey, David Draper, Sheri Barnes, Yewei Xing, Derrik Germain, Lauren Kucharczyk, Roys Stacey. Investigating CAR-T cell efficacy and activation in the disseminated NALM6-luc human B-cell acute lymphoblastic leukemia model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4002.

The relationship between hematologic malignancies on male hypogonadism: a scoping review.

The associated symptoms of hypogonadism have been reported in patients with various types of cancer. However, the prevalence and significance of hypogonadism among certain hematologic malignancies have not been completely summarized in recent literature. In this review we aimed to examine the current literature on hypogonadism in patients with hematologic malignancies, with emphasis on leukemias, lymphomas, and multiple myeloma (MM). This review included relevant studies published before July 2023 that were retrieved through a search of PubMed using the keywords "hematologic cancer," "hematologic malignancy," blood cancer," "leukemia," "lymphoma," "hypogonadism," "multiple myeloma," and "testosterone." The search yielded 214 studies, of which 21 met the inclusion criteria. Commonly reported findings were that patients who had received hematopoietic stem cell therapy for acute lymphoblastic leukemia and acute myelogenous leukemia as children had laboratory-confirmed hypogonadism as adults. However, the impact of these diseases on hypogonadal symptoms was variable in these studies.Studies reporting on lymphoma and hypogonadism had mixed results, with some studies finding that the degree of cytotoxic chemotherapy was associated with hypogonadism, while others showed no correlation. Regardless, multiple studies found that hypogonadism secondary to lymphoma treatment and symptoms of hypogonadism had no apparent association.The most comprehensive assessment of the frequency of hypogonadism in an MM cohort found that 74% of 561 MM patients were classified as hypogonadal compared to 33% of patients in a control population. Testosterone supplementation was found to lower interleukin-6 levels, which could potentially help manage some of the adverse effects of MM, including decreased bone mineral density. There is a relationship between hematologic malignancies and hypogonadism, which is likely multifactorial. In this review we established that the most plausible factors are related to the secondary effects of gonadotoxic treatments and/or systemic inflammatory responses to the diseases.

Germline variants in patients developing second malignant neoplasms after therapy for pediatric acute lymphoblastic leukemia—a case-control study

Germline variants in patients developing second malignant neoplasms after therapy for pediatric acute lymphoblastic leukemia—a case-control study

CD99 tumor associated antigen is a potential target for antibody therapy of T-cell acute lymphoblastic leukemia.

Monoclonal antibodies (mAbs) are an effective drug for targeted immunotherapy in several cancer types. However, so far, no antibody has been successfully developed for certain types of cancer, including T-cell acute lymphoblastic leukemia (T-ALL). T-ALL is an aggressive hematologic malignancy. T-ALL patients who are treated with chemotherapeutic drugs frequently relapse and become drug resistant. Therefore, antibody-based therapy is promising for T-ALL treatment. To successfully develop an antibody-based therapy for T-ALL, antibodies that induce death in malignant T cells but not in nonmalignant T cells are required to avoid the induction of secondary T-cell immunodeficiency. In this review, CD99 tumor associated antigen, which is highly expressed on malignant T cells and lowly expressed on nonmalignant T cells, is proposed to be a potential target for antibody therapy of T-ALL. Since certain clones of anti-CD99 mAbs induce apoptosis only in malignant T cells, these anti-CD99 mAbs might be a promising antibody drug for the treatment of T-ALL with high efficiency and low adverse effects. Moreover, over the past 25 years, many clones of anti-CD99 mAbs have been studied for their direct effects on T-ALL. These outcomes are gathered here.

Effects of allopurinol on 6-mercaptopurine metabolism in unselected patients with pediatric acute lymphoblastic leukemia: a prospective phase II study.

Allopurinol can be used in maintenance therapy (MT) for pediatric acute lymphoblastic leukemia (ALL) to mitigate hepatic toxicity in patients with skewed 6- mercaptopurine metabolism. Allopurinol increases the erythrocyte levels of thioguanine nucleotides (e-TGN), which is the proposed main mediator of the antileukemic effect and decreases methyl mercaptopurine (e-MeMP) levels, associated with hepatotoxicity. We investigated the effects of allopurinol in thiopurine methyltransferase (TPMT) wild-type patients without previous clinical signs of skewed 6MP metabolism. Fifty-one patients from Sweden and Finland were enrolled in this prospective beforeafter trial during ALL MT. Mean e-TGN increased from 280 nmol/mmol Hb after 12 weeks of standard MT to 440 after 12 weeks of MT with addition of allopurinol 50 mg/m2 (p.

Enhanced potency of immunotherapy against B-cell precursor acute lymphoblastic leukemia by combination of an Fc-engineered CD19 antibody and CD47 blockade.

CD19-directed immunotherapy has become a cornerstone in the therapy of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). CD19-directed cellular and antibody-based therapeutics have entered therapy of primary and relapsed disease and contributed to improved outcomes in relapsed disease and lower therapy toxicity. However, efficacy remains limited in many cases due to a lack of therapy response, short remission phases, or antigen escape. Here, BCP-ALL cell lines, patient-derived xenograft (PDX) samples, human macrophages, and an in vivo transplantation model in NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) mice were used to examine the therapeutic potency of a CD19 antibody Fc-engineered for improved effector cell recruitment (CD19-DE) and antibody-dependent cellular phagocytosis (ADCP), in combination with a novel modified CD47 antibody (Hu5F9-IgG2σ). For the in vivo model, only samples refractory to CD19-DE monotherapy were chosen. Hu5F9-IgG2σ enhanced ADCP by CD19-DE in various BCP-ALL cell line models with varying CD19 surface expression and cytogenetic backgrounds, two of which contained the KMT2A-AFF1 fusion. Also, the antibody combination was efficient in inducing ADCP by human macrophages in pediatric PDX samples with and adult samples with and without KMT2A-rearrangement in vitro. In a randomized phase 2-like PDX trial using seven KMT2A-rearranged BCP-ALL samples in NSG mice, the CD19/CD47 antibody combination proved highly efficient. Our findings support that the efficacy of Fc-engineered CD19 antibodies may be substantially enhanced by a combination with CD47 blockade. This suggests that the combination may be a promising therapy option for BCP-ALL, especially in relapsed patients and/or patients refractory to CD19-directed therapy.

Assessment on the use of allopurinol to improve safety and efficacy of mercaptopurine in pediatric patients with Acute Lymphoblastic Leukemia and Lymphoma during maintenance therapy.

Mercaptopurine is an important component of acute lymphoblastic leukemia (ALL) and lymphoma (LLy) maintenance therapy. The 6-thioguanine nucleosides (6-TGN) are believed to be the primary contributor to myelosuppression and immunosuppressive effects, while 6-methylmercaptopurine (6-MMPN) is believed to be responsible for several toxicities including hepatotoxicity, pancreatitis, and hypoglycemia. Previous reports suggest the addition of allopurinol may reduce these toxicities. To assess the use of allopurinol to improve both safety and efficacy of mercaptopurine in pediatric patients with ALL and LLy during maintenance therapy. Secondary objectives included evaluating patient tolerability and skewed metabolism. In addition, we also analyzed mercaptopurine daily dose reduction upon allopurinol initiation. The primary endpoint was time within goal ANC prior to and after initiation of allopurinol. Secondary endpoints included; improvement in selective toxicities (hepatotoxicity, pancreatitis, and hypoglycemia) and 6-MMPN to 6-TGN ratio prior to and after allopurinol initiation. In addition, an exploratory endpoint assessing mercaptopurine daily dose reduction prior to and after allopurinol initiation was included. Sixteen patients met inclusion criteria and 15 (94%) of which were included in this study. Median percent of maintenance days within goal ANC prior to and after initiation of allopurinol was 27.8 (IQR 22.6-44.9) and 41.6 (IQR 20.2-58.2) respectively. All patients experienced selective toxicities; 15 (100%) hepatotoxicity, 1 (7%) pancreatitis, and 3 (20%) hypoglycemia. Improvement of toxicities was seen in 13/15 (87%), 1/1 (100%), and 2/3 (67%) respectively. Average 6-MMPN:6-TGN ratio prior to allopurinol initiation was 304:1 and after, allopurinol initiation improved to 15:1, resulting in a 95% reduction. Average mercaptopurine dose prior to and after allopurinol initiation decreased by about 56% (63 to 28 mg/m2 /day). Results suggest that the use of allopurinol in pediatric patients with ALL and LLy receiving mercaptopurine during maintenance therapy is both safe and effective.

Increase in peg-asparaginase clearance as a predictor for inactivation in patients with acute lymphoblastic leukemia

Asparaginase is an essential component of acute lymphoblastic leukemia (ALL) therapy, yet its associated toxicities often lead to treatment discontinuation, increasing the risk of relapse. Hypersensitivity reactions include clinical allergies, silent inactivation, or allergy-like responses. We hypothesized that even moderate increases in asparaginase clearance are related to later inactivation. We therefore explored mandatory monitoring of asparaginase enzyme activity (AEA) in patients with ALL aged 1–45 years treated according to the ALLTogether pilot protocol in the Nordic and Baltic countries to relate mean AEA to inactivation, to build a pharmacokinetic model to better characterize the pharmacokinetics of peg-asparaginase and assess whether an increased clearance relates to subsequent inactivation. The study analyzed 1631 real-time AEA samples from 253 patients, identifying inactivation in 18.2% of the patients. This inactivation presented as mild allergy (28.3%), severe allergy (50.0%), or silent inactivation (21.7%). A pharmacokinetic transit compartment model was used to describe AEA-time profiles, revealing that 93% of patients with inactivation exhibited prior increased clearance, whereas 86% of patients without hypersensitivity maintained stable clearance throughout asparaginase treatment. These findings enable prediction of inactivation and options for either dose increments or a shift to alternative asparaginase formulations to optimize ALL treatment strategies.

Chemotherapy-related toxicities follow a typical pattern in children treated for acute lymphoblastic leukaemia.

Acute lymphoblastic leukaemia (ALL) therapy has been associated with a significant burden of toxicities. The aim of this study was to describe the full spectrum of toxic effects associated with childhood ALL. Toxicity-related data were collected from the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL-2008 toxicity registry, in which data on 19 clinically relevant toxicities were registered during ALL treatment, and from patient medical records. All patients treated according to the NOPHO ALL-2008 protocol in Oulu University Hospital between 2008 and 2020 were included in the study. The cohort consisted of 73 patients, 38 of whom were male. Mean age at diagnosis was 6.6 ± 4.2 (range 1.4-16.0) years. All but one of the patients developed at least one treatment-related toxicity and more than half had multiple toxicities. Female sex and older age were associated with a higher tendency towards toxicity. The most common toxicity was vincristine-induced peripheral neuropathy, which was observed in 70 patients. Most toxicities were moderate or severe, but even mild toxicities often affected leukaemia treatment. Moderate and severe treatment-related toxicities are common, and most toxicities occur in a typical pattern in relation to the treatment phases.

Genomic analysis of venous thrombosis in children with acute lymphoblastic leukemia from diverse ancestries.

Venous thrombosis is a common adverse effect of modern therapy for acute lymphoblastic leukemia (ALL). Prior studies to identify risks of thrombosis in pediatric ALL have been limited by genetic screens of pre-identified genetic variants or genome- wide association studies (GWAS) in ancestrally uniform populations. To address this, we performed a retrospective cohort evaluation of thrombosis risk in 1,005 children treated for newly diagnosed ALL. Genetic risk factors were comprehensively evaluated from genome-wide single nucleotide polymorphism (SNP) arrays and were evaluated using Cox regression adjusting for identified clinical risk factors and genetic ancestry. The cumulative incidence of thrombosis was 7.8%. In multivariate analysis, older age, T-lineage ALL, and non-O blood group were associated with increased thrombosis while non-low-risk treatment and higher presenting white blood cell count trended toward increased thrombosis. No SNP reached genome-wide significance. The SNP most strongly associated with thrombosis was rs2874964 near RFXAP (G risk allele; P=4x10-7; hazard ratio [HR] =2.8). In patients of non-European ancestry, rs55689276 near the α globin cluster (P=1.28x10-6; HR=27) was most strongly associated with thrombosis. Among GWAS catalogue SNP reported to be associated with thrombosis, rs2519093 (T risk allele, P=4.8x10-4; HR=2.1), an intronic variant in ABO, was most strongly associated with risk in this cohort. Classic thrombophilia risks were not associated with thrombosis. Our study confirms known clinical risk features associated with thrombosis risk in children with ALL. In this ancestrally diverse cohort, genetic risks linked to thrombosis risk aggregated in erythrocyte-related SNP, suggesting the critical role of this tissue in thrombosis risk.

Study of the Application of CAR-T Cell Therapy in Acute Lymphocytic Leukemia

Currently, the acute lymphocytic leukemia (ALL), which is a severe blood cancer that mostly found in children, can applied with the most updated CAR-T cell therapy for the cure. ALL incidence rate is around fifteen in one hundred thousand people, which is just lower than the incidence rate of Chronic Lymphocytic Leukemia. And the ALL occupied one-fifth of the leukemia cases. With the application of CAR-T cell therapy, ALL can be cured with higher long-term survival rate. But the CAR-T cell therapy brings some negative impact towards patient body like Cytokine Release Syndrome (CRS). The limitations and adverse actions of the therapy needs to be overcome or minimized to achieve the best prospect of treating patients. In this paper, the first part will briefly introduce present situations of ALL and the CAR-T cell therapy, and the following parts will explain mechanism of CAR-T cell therapy, limitations of the therapy on this disease, and future development of the therapy.

Determinants of outcomes and advances in CD19-directed chimeric antigen receptor therapy for B-cell acute lymphoblastic leukemia.

Relapsed and refractory B-cell acute lymphoblastic leukemia (B-ALL) is an aggressive B-cell neoplasm associated with poor outcomes. Conventional multiagent chemotherapy and bispecific antibody therapy may induce remission; however, relapse rates remain high and overall survival is poor. Chimeric antigen receptor T-cell (CAR-T) therapy provides durable, deep complete remission, and long-term cures in relapsed and refractory B-ALL. However, with this new treatment modality, 10%-30% of patients do not achieve remission, and over 50% experience relapse after therapy. Currently, there are two approved CD19-specific CAR-T cell constructs in B-ALL, Tisagenlecleucel and Brexucabtagene Autoleucel by the United States Food and Drug Administration, and the European Medicines Agency (EMA). In this review, we discuss patients, disease, and CAR-T predictors of outcomes in B-ALL. We describe the two approved CD19-directed CAR-T cell products, review the current literature, and discuss factors associated with high risks of therapy failure and future direction in CAR-T cell therapy for B-ALL.

Assessing Risk Classification in Medication-Induced Diabetes during Induction Therapy in Pediatric Acute Lymphoblastic Leukemia

Medication-induced diabetes (MID) is common during induction therapy for pediatric acute lymphoblastic leukemia (ALL) and has potentially significant negative consequences. Reported risk factors for MID are variable with limited data comparing patients treated with standard-risk (SR) vs. high-risk (HR) regimens. This study aims to evaluate the incidence and risk factors for MID during induction in patients with ALL from the Maritimes over a 20-year period. We performed a retrospective single-center study of 262 patients (142 males, 120 females) diagnosed with ALL at IWK Health in Halifax, Nova Scotia, Canada, from 2000 to 2019. Older age, higher body mass index, greater central nervous system status, Trisomy 21, and prednisone steroid type were risk factors associated with MID in our cohort. HR patients developed significantly more complications than SR patients including MID and infection. Screening for MID should be routine during ALL induction treatment, particularly in those with HR disease.

Hybrid Email and Outpatient Clinics to Optimize Maintenance Therapy in Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia treatment includes an outpatient (OP)-based 2-year maintenance therapy (MT). Over an 8-year period, patients were transited from only OP to a hybrid e-clinic/OP-clinic model. Electronic and patient-held medical records of acute lymphoblastic leukemia patients 1 to 18 years old during MT were used to analyze demographics, drug doses, treatment response and cost. A survey evaluated family satisfaction with the hybrid service. Four hundred and seventy-eight children, all with at least 1 year of MT from March 13, 2014 to March 24, 2022 were grouped into 4 treatment eras, representing the transition from all OP (era 1) to the current hybrid MT practice (era 4). Cohort demographics were similar across all eras. With transition to era 4, OP visits decreased to a third (16 to 18/48 visits). Practice optimization in era 2 resulted in higher MT dose intensity in subsequent eras (era 1: median 82% [interquartile range, 63 to 97]; era 2: 93% [73 to 108]; era 3: 88% [68 to 106]; era 4: 90% [74 to 114], P <0·0001), with no differences in absolute neutrophil count or neutropenia-related toxicity ( P =0.8). The hybrid service reduced MT expenses by ~50% and families (133/156, 85%) reported being very satisfied. Our experience indicates that a hybrid model is feasible, effective and less burdensome for patients and families.