Blinatumomab in Pediatric Acute Lymphoblastic Leukemia-From Salvage to First Line Therapy (A Systematic Review)

The evolution of nutritional care in children and young people with acute lymphoblastic leukaemia: a narrative review

BACKGROUND

Acute lymphoblastic leukaemia (ALL) is the most common paediatric malignancy in the world. Advances in treatment protocols have resulted in survival rates of >80% in most high-income countries (HIC); however, children and young people (CYP) with ALL continue to face significant nutrition-related challenges during treatment.

METHODS

This narrative review outlines the changing landscape of treatment and survivorship for CYP with ALL and the advances in nutrition knowledge that call for changes to clinical nutrition practice.

RESULTS

The incidence of ALL has remained stable in HIC; however, there have been significant advances in survival over the past 30 years. Overweight and obesity are increasingly prevalent in CYP with ALL at diagnosis, during treatment and in survivorship. Coupled with poor diet quality, high-energy and saturated fat intakes, altered eating behaviours and inactivity, this necessitates the need for a shift in nutrition intervention. Undernutrition remains a concern for CYP with high-risk treatment protocols where oral or enteral nutrition support remains a cornerstone of maintaining nutrition status.

CONCLUSIONS

With improved treatment protocols and high survival rates, a shift to focusing on diet quality, prevention of excessive weight gain and obesity during treatment and survivorship is necessary.

A Comprehensive Review of the Mechanisms and Clinical Development of Monoclonal Antibodies in Cancer Therapy

Cancer is still the disease that ranks first in human mortality in the twenty-first century. In the last 20 years, the concept of molecular targeted therapy has come to the fore with the use of small molecule agents or signal transduction inhibitors that show anticancer effects for certain types of cancer. Monoclonal antibodies, which have a therapeutic effect, especially by providing signal transduction inhibition, are used clinically as first-line treatment in various types of cancer. Molecular targeted therapies are critical for eliminating the adverse effects and drug resistance problems that occur in traditional cancer treatments. This review summarizes current information on various targeted therapeutic agents, including the structure and classification of monoclonal antibodies, their production methods and mechanisms of action, the monoclonal antibodies used in clinical trials, the complement system mechanism and cancer relationship, and the relationship between complement-dependent cytotoxicity and monoclonal antibodies.

Aptamer sgc8-Modified PAMAM Nanoparticles for Targeted siRNA Delivery to Inhibit BCL11B in T-Cell Acute Lymphoblastic Leukemia

Introduction

T-cell acute lymphoblastic leukemia (T-ALL) is a malignant hematological disease with limited targeted therapy options. Overexpression of B-cell lymphoma/leukemia 11B is frequently observed in T-ALL and contributes to leukemogenesis. Knockdown of BCL11B inhibits T-ALL cell proliferation and induces apoptosis, making it a potential therapeutic target. However, the clinical application of siRNA therapies is hindered by challenges such as poor delivery efficiency and limited clinical outcomes.

Methods

We developed a targeted delivery system for BCL11B siRNA (siBCL11B) using generation 5 polyamidoamine (G5-PAMAM) dendrimers conjugated with the sgc8 aptamer, which specifically binds to the T-ALL cell membrane protein PTK7. This nanoparticle, designated G5-sgc8-siBCL11B, was designed to selectively deliver siRNA to T-ALL cells. In vitro and in vivo experiments were conducted to evaluate its therapeutic efficacy and safety.

Results

We demonstrate that sgc8-conjugated siBCL11B nanoparticles selectively and efficiently target BCL11B-overexpressing T-ALL cells, significantly inhibiting cell viability and promoting apoptosis while exhibiting minimal impact on the viability of normal T cells. In T-ALL mouse model studies, G5-sgc8-siBCL11B and G5-siBCL11B significantly inhibited the progression of T-ALL in vivo, extending the survival of mice compared to the control (CTR), G5, and G5-sgc8 groups. Although there was no significant difference in survival between the G5-sgc8-siBCL11B and G5-siBCL11B groups, a trend towards improved survival was observed (p = 0.0993).

Conclusion

The G5-sgc8-siBCL11B nanoparticle system demonstrated efficient delivery and significant therapeutic efficacy, highlighting its potential as a promising novel approach for the treatment of T-ALL.

Delivery of Care for Pediatric Patients Receiving Blinatumomab: A Children's Oncology Group Study

BACKGROUND

Blinatumomab is an immunotherapy agent used in pediatric oncology for the treatment of B-lineage acute lymphoblastic leukemia. Administration of blinatumomab, via continuous 28-day infusion cycles, can present multiple decision points and challenges related to patient care. Nurses are at the forefront of coordinating and delivering care for patients receiving blinatumomab.

OBJECTIVE

To describe the current state of practice across Children's Oncology Group (COG) member institutions regarding blinatumomab administration in both inpatient and home/outpatient settings.

METHODS

Between August and December 2021, a cross-sectional survey was used to determine current institutional practices related to blinatumomab administration. A single targeted respondent who was actively engaged in coordinating blinatumomab administration completed the survey on behalf of each COG institution.

RESULTS

Survey participation rate was 78% (150/192). During the first 28-day blinatumomab cycle, 71 institutions (53%) reported patient hospital stays between 73 hours and 7 days; 42 (31%) reported hospital stays ≤72 hours, and only 12 (9%) reported hospitalization for the full 28-day infusion. Small- to medium-size institutions were more likely to report longer hospitalizations ( P = .03). Most blinatumomab administration occurred in the outpatient setting, with low rates of unplanned clinic/emergency room visits.

CONCLUSIONS

The majority of COG institutions have navigated the complex coordination of care required for children to receive blinatumomab at home. Wide variations in practice were noted across institutions.

IMPLICATIONS FOR PRACTICE

This study describes current institutional practices surrounding administration of 28-day blinatumomab infusions in children with leukemia and offers a starting point for institutional benchmarking and standardization of practice.

Blinatumomab infusion interruptions in pediatric patients rarely lead to readmission

Blinatumomab is a bispecific T-cell engager administered as a 28-day continuous infusion. Infusions can be associated with interruptions requiring support from clinical staff, but the frequency of interventions with outpatient blinatumomab has not been characterized. This study is a single-center, retrospective review of patients who received blinatumomab between December 3, 2014 and October 31, 2021 to determine frequency and type of interventions. Forty patients received blinatumomab for 69 cycles. Clinical staff intervention was required in 31 (45%) cycles, only six (8.7%) cycles needed readmission. Management of outpatient blinatumomab infusions requires education and training of clinical staff and caregivers to quickly troubleshoot interruptions.

Inotuzumab ozogamicin combined with chemotherapy in pediatric B-cell precursor CD22+ acute lymphoblastic leukemia: results of the phase IB ITCC-059 trial

Inotuzumab ozogamicin (InO) is a CD22-directed antibody conjugated with calicheamicin. The phase IB of the ITCC-059 trial tested InO combined with chemotherapy in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Relapsed /refractory CD22+ BCP-ALL pediatric patients were enrolled. The primary objective was to establish the recommended phase II dose (RP2D). Secondary objectives included preliminary efficacy and tolerability. InO was combined with 1.5 mg/m2 of vincristine (days 3, 10, 17, 24), 20 mg/m2 of dexamethasone (2 5-day blocks, then amended), and intrathecal therapy. A rolling-6 design was used testing InO from 0.8 to 1.8 mg/m2/cycle. Between May 2020 and April 2022, 30 patients were treated, and 29 were evaluable for dose limiting toxicities (DLT). At 1.1 mg/m2/cycle, two of four patients had DLT (liver toxicity). InO was de-escalated to 0.8 mg/m2/cycle (N=6) without DLT while awaiting a protocol amendment to reduce dexamethasone dose to 10 mg/m2. Post amendment, InO was re-escalated to 1.1 mg/m2/cycle (N=6, 1 DLT), then to 1.4 mg/m2/ cycle (N=3, no DLT), and finally to 1.8 mg/m2/cycle (N=7, 1 DLT). Three additional patients were treated in an expansion cohort. The pooled response rate was 80% (24/30; 95% confidence interval [CI]: 61.4-92.3) and, among responders, 66.7% achieved minimal residual disease negativity. The RP2D of InO combined with vincristine, dexamethasone and intrathecal therapy was declared at 1.8 mg/m2/cycle (1.5 mg/m2/cycle after remission) in a fractioned schedule. This combination showed a response rate similar to the single agent cohorts of this trial, with liver toxicity issues at the initial higher dexamethasone dose (clinicaltrials gov. Identifier: NTR5736).

A Quality Approach to Blinatumomab Delivery in Pediatric Oncology: A Children's Oncology Group Study

Background: Blinatumomab is a promising immunotherapy agent that has been shown to improve survival outcomes in children diagnosed with relapsed B-lineage acute lymphoblastic leukemia. Expanded use of blinatumomab in the treatment of childhood cancer is expected; however, clinician perspectives regarding administering this agent in healthcare and home settings have not been explored. Method: Semistructured interviews were conducted with clinicians (N = 13) from pediatric institutions across the United States and Canada. Qualitative data were analyzed using a constant comparative analysis three-stage method. Results: Participants were primarily nurses (92%), female (77%), and had greater than 10 years of pediatric oncology experience. The selective code and overarching theme identified was "A quality approach to blinatumomab delivery in pediatric oncology." Clinicians described detailed processes that were created and implemented to promote a common goal of safe blinatumomab administration across the continuum of care. Clinicians shared how they engaged in planning activities and considered a variety of factors prior to and during blinatumomab administration. Clinicians also expressed a need to reflect and evaluate on previous patient experiences to create new or revise existing processes and workflows. Communication was also central to clinicians' work. Clinicians provided recommendations to assist others with blinatumomab administration and offered suggestions for items that could help with implementing future clinical trials containing similar agents. Discussion: Findings suggest nurses are pivotal to establishing processes which support safe administration of immunotherapies, such as blinatumomab, while also considering patient-specific needs and promoting quality of life.

Atypical Presentation of B-Cell Lymphoblastic Lymphoma: Solitary Scalp Mass in a Pediatric Patient

B-cell lymphoblastic lymphoma (B-LBL) is a subtype of non-Hodgkin lymphoma characterized by the proliferation of abnormal B-cell lymphoblasts in lymphoid tissues. Typical presentations include lymphadenopathy, mediastinal mass, and involvement of organs such as the liver and spleen, but extranodal sites can also be affected. A previously healthy 20-month-old male child presented to the pediatric surgery clinic with a two-month history of a painless, progressively enlarging mass on the scalp as well as postauricular mass consistent with an enlarged lymph node. Ultrasound of the mass near the vertex demonstrated a hypoechoic complex cystic lesion for which excision was indicated. Preoperatively, acute enlargement of the entire postauricular lymphatic chain was noted. Intraoperatively, the scalp mass was noted to be firm with calcified tissue and no identifiable cystic or infectious components. The mass and part of the overlying skin were excised. Pathologic evaluation was consistent with B-LBL. The patient was therefore referred to a pediatric oncologist for further evaluation and management. Bone marrow examination revealed greater than 25% blasts in the clot section, consistent with B-ALL. He was promptly initiated on induction therapy with maintenance chemotherapy to ensure continued remission. This case highlights the atypical presentation of B-cell lymphoblastic leukemia/lymphoma (B-ALL/LBL) as a scalp mass in a 20-month-old male. It underscores the importance of considering malignancy in the differential diagnosis of unusual masses. Prompt collaboration between pediatric surgeons and oncologists facilitates timely diagnosis and initiation of appropriate treatments for optimal outcomes.

Immune-inflammatory modulation by natural products derived from edible and medicinal herbs used in Chinese classical prescriptions

BACKGROUND

Edible and medicinal herbs1 (EMHs) refer to a class of substances with dual attribution of food and medicine. These substances are traditionally used as food and also listed in many international pharmacopoeias, including the European Pharmacopoeia, the United States Pharmacopoeia, and the Chinese Pharmacopoeia. Some classical formulas that are widely used in traditional Chinese medicine include a series of EMHs, which have been shown to be effective with obvious characteristics and advantages. Notably, these EMHs and Chinese classical prescriptions2 (CCPs) have also attracted attention in international herbal medicine research because of their low toxicity and high efficiency as well as the rich body of experience for their long-term clinical use.

PURPOSE

Our purpose is to explore the potential therapeutic effect of EMHs with immune-inflammatory modulation for the study of modern cancer drugs.

STUDY DESIGN

In the present study, we present a detailed account of some EMHs used in CCPs that have shown considerable research potential in studies exploring modern drugs with immune-inflammatory modulation.

METHODS

Approximately 500 publications in the past 30 years were collected from PubMed, Web of Science and ScienceDirect using the keywords, such as natural products, edible and medicinal herbs, Chinese medicine, classical prescription, immune-inflammatory, tumor microenvironment and some related synonyms. The active ingredients instead of herbal extracts or botanical mixtures were focused on and the research conducted over the past decade were discussed emphatically and analyzed comprehensively.

RESULTS

More than ten natural products derived from EMHs used in CCPs are discussed and their immune-inflammatory modulation activities, including enhancing antitumor immunity, regulating inflammatory signaling pathways, lowering the proportion of immunosuppressive cells, inhibiting the secretion of proinflammatory cytokines, immunosuppressive factors, and inflammatory mediators, are summarized.

CONCLUSION

Our findings demonstrate the immune-inflammatory modulating role of those EMHs used in CCPs and provide new ideas for cancer treatment in clinical settings.

Blinatumomab as postremission therapy replaces consolidation and substantial parts of maintenance chemotherapy and results in stable MRD negativity in children with newly diagnosed B-lineage ALL

The bispecific T cell-binding antibody blinatumomab (CD19/CD3) is widely and successfully used for the treatment of children with relapsed or refractory B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Here, we report the efficacy of a single course of blinatumomab instead of consolidation chemotherapy to eliminate minimal residual disease (MRD) and maintain stable MRD-negativity in children with primary BCP-ALL.Between February 2020 and November 2022, 177 children with non-high-risk BCP-ALL were enrolled in the ALL-MB 2019 pilot study (NCT04723342). Patients received the usual risk-adapted induction therapy according to the ALL-MB 2015 protocol. Those who achieved a complete remission at the end of induction (EOI) received treatment with blinatumomab immediately after induction at a dose of 5 μg/m2/day for 7 days and 21 days at a dose of 15 μg/m2/day, followed by 12 months of maintenance therapy. MRD was measured using multicolor flow cytometry (MFC) at the EOI, then immediately after blinatumomab treatment, and then four times during maintenance therapy at 3-month intervals.All 177 patients successfully completed induction therapy and achieved a complete hematological remission. In 174 of these, MFC-MRD was measured at the EOI. 143 patients (82.2%) were MFC-MRD negative and the remaining 31 patients had varying degrees of MFC-MRD positivity.MFC-MRD was assessed in all 176 patients who completed the blinatumomab course. With one exception, all patients achieved MFC-MRD negativity after blinatumomab, regardless of the MFC-MRD score at EOI. One adolescent girl with high MFC-MRD positivity at EOI remained MFC-MRD positive. Of 175 patients who had completed 6 months of maintenance therapy, MFC-MRD data were available for 156 children. Of these, 155 (99.4%) were MFC-MRD negative. Only one boy with t(12;21) (p13;q22)/ETV6::RUNX1 became MFC-MRD positive again. The remaining 174 children had completed the entire therapy. MFC-MRD was examined in 154 of them, and 153 were MFC-MRD negative. A girl with hypodiploid BCP-ALL showed a reappearance of MFC-MRD with subsequent relapse.In summary, a single 28-day course of blinatumomab immediately after induction, followed by 12 months of maintenance therapy, is highly effective in achieving MRD-negativity in children with newly diagnosed non-high risk BCP-ALL and maintaining MRD-negative remission at least during the treatment period.

Blinatumomab in Children with MRD-Positive B-Cell Precursor Acute Lymphoblastic Leukemia: A Report of 11 Cases

Background/Objectives: Relapsed B-cell acute lymphoblastic leukemia (B-ALL) remains an unresolved matter of concern regarding adverse outcomes. This case study aimed to evaluate the effectiveness of blinatumomab, with or without door lymphocyte infusion (DLI), in treating measurable residual disease (MRD)-positive B-ALL. Methods: All patients who received blinatumomab salvage therapy were included in this study. Eleven patients were included in the study. All patients were evaluated for MRD-negativity. Results: Before starting blinatumomab therapy, seven patients tested positive for MRD, three tested negative, and one had refractory disease. Hematopoietic cell transplantation (HCT) was reserved for five patients with persistent MRD. Six patients became MRD-negative and subsequent HCT was not performed. Only two patients relapsed; one patient died of relapse, and the other one received carfilzomib-based therapy and was MRD-negative thereafter. Nine patients were MRD-negative at a median follow-up of 28 months (15-52 months). Two of three MRD-positive post-transplant patients remained in complete molecular remission after preemptive DLI at the last follow-up date. In the first salvage, blinatumomab may achieve complete remission and bridging to HCT in pediatric patients with end-of-induction MRD-positive B-cell precursor ALL. Conclusions: The decision on how to treat post-transplant relapse continues to affect survival outcomes. Blinatumomab combined with DLI may extend the armamentarium of release options for high-risk pediatric patients. This approach is encouraging for high-risk ALL patients who are MRD-positive post-transplantation.

Spontaneous Remission of Acute Lymphoblastic Leukemia Following Candida tropicalis Fungemia

Spontaneous remission (SR) in acute lymphoblastic leukemia (ALL) is a poorly understood phenomenon that has been sporadically reported in medical literature for over a century, and the molecular and immunologic mechanisms of remission pose interesting clinical questions. Furthermore, the often-transient nature of these remissions poses a challenge to physicians in formulating an approach to treatment. We report on a rare case of Candida tropicalis sepsis in a three-year-old female with high-risk ALL who received less than two months of treatment prior to sepsis and subsequent SR.

The outcome of relapsed childhood acute lymphoblastic leukemia after allogeneic hematopoietic stem-cell transplantations: A single-center experience

In children with high-risk childhood acute leukemia who undergo allogeneic hematopoietic stem-cell transplantation (allo-HSCT), relapse is still the leading cause of treatment failure. The prognosis is poor, yet prospective studies have only limited data on risk factors and outcomes. We aimed to understand the outcomes and prognostic factors for patients with acute lymphoblastic leukemia (ALL) who relapsed following allo-HSCT. We analyzed retrospectively 46 children with childhood acute lymphoblastic leukemia who had relapsed after receiving their first alloHSCT. All these patients received salvage chemotherapy which consisted of fludarabine, cytarabine, and idarubicin before performing a second alloHSCT. The median follow-up of the 46 patients after the first transplantation was 366 days. The median time from first allo-HSCT to relapse was 278.4 ± 238.4 days. Forty-six patients received salvage chemotherapy before the second alloHSCT, and CR was achieved in 32 of 46 patients. However, only 17 (37%) of 46 patients received a second allo-HSCT, and 15 of 46 patients died from disease progression, infections, and bleeding. Twelve patients are still alive after the second allo-HSCT. Two-year overall survival (OS) was 38.9%. Local therapy was given to 10 (21.8%) patients, either as part of systemic therapy or alone. In multivariate analyses, the time of relapse and curative salvage therapy with a second allo-HSCT were identified as significant prognostic factors for OS. Children with leukemia who had relapsed after the first allo-HSCT received salvage chemotherapy. Our statistical analysis showed that the second HSCT could be beneficial for outcomes if patients relapsed beyond 180 days of the first allo-HSCT.

Immune therapies of B-cell acute lymphoblastic leukaemia in children and adults

B-cell acute lymphoblastic leukaemia (B-cell ALL) is a common haematologic cancer in children and adults. About 10 percent of children and 50 percent of adults fail to achieve a histological complete remission or subsequently relapse despite current anti-leukaemia drug therapies and/or haematopoietic cell transplants. Several new immune therapies including monoclonal antibodies and chimeric antigen receptor (CAR)-T-cells are proved safe and effective in this setting. We review data on US Food and Drug Administration (FDA)-approved immune therapies for B-cell ALL in children and adults including blinatumomab, inotuzumab ozogamicin, tisagenlecleucel, and brexucabtagene autoleucel. We also summarize pharmaco-dynamics, pharmaco-kinetics, and pharmaco-economics of these interventions.

Revolutionizing cancer treatment: comprehensive insights into immunotherapeutic strategies

Cancer, characterized by the uncontrolled proliferation of aberrant cells, underscores the imperative for innovative therapeutic approaches. Immunotherapy has emerged as a pivotal constituent in cancer treatment, offering improved prognostic outcomes for a substantial patient cohort. Noteworthy for its precision, immunotherapy encompasses strategies such as adoptive cell therapy and checkpoint inhibitors, orchestrating the immune system to recognize and selectively target malignant cells. Exploiting the specificity of the immune response renders immunotherapy efficacious, as it selectively targets the body's immune milieu. Diverse mechanisms underlie cancer immunotherapies, leading to distinct toxicity profiles compared to conventional treatments. A remarkable clinical stride in the anticancer resources is immunotherapy. Remarkably, certain recalcitrant cancers like skin malignancies exhibit resistance to radiation or chemotherapy, yet respond favorably to immunotherapeutic interventions. Notably, combination therapies involving chemotherapy and immunotherapy have exhibited synergistic effects, enhancing overall therapeutic efficacy. Understanding the pivotal role of immunotherapy elucidates its complementary value, bolstering the therapeutic landscape. In this review, we elucidate the taxonomy of cancer immunotherapy, encompassing adoptive cell therapy and checkpoint inhibitors, while scrutinizing their distinct adverse event profiles. Furthermore, we expound on the unprecedented potential of immunogenic vaccines to bolster the anticancer immune response. This comprehensive analysis underscores the significance of immunotherapy in modern oncology, unveiling novel prospects for tailored therapeutic regimens.

Case Report: CD19 and CD20 monoclonal antibodies with sequential chemotherapy for refractory acute B-lymphocytic leukemia in children

Objective

This paper observes the efficacy of chemotherapy combined with CD19 and CD20 monoclonal antibodies in clearing minimal residual disease (MRD) and bridging transplantation for refractory acute B-lymphoblastic leukemia (B-ALL) in children and reviews the literature.

Methods

A 4-year-old boy diagnosed with B-ALL in our hospital was treated with the SCCLG-ALL-2016 protocol. MRD and gene quantification decreased after induction but remained persistently positive, with poor efficacy. After this patient received three cycles of consolidation chemotherapy combined with blinatumomab and rituximab, MRD and fusion gene quantification became negative, and he received allogeneic hematopoietic stem cell transplantation (allo-HSCT).

Results

During the use of monoclonal antibodies, neurotoxicity, CRS, or other side effects did not occur. Before transplantation, MRD became negative, and the bone marrow had been in complete remission since transplantation (13 months).

Conclusion

Chemotherapy combined with blinatumomab for refractory B-ALL in children can bring a better remission rate for patients and is a means of bridging transplantation. Nevertheless, sequential CD20 monoclonal antibody therapy is the first report , and no adverse effects were observed in our case. It is well tolerated and can be used as one of the treatments for refractory B-ALL.

Recent advancement in targeted therapy and role of emerging technologies to treat cancer

Cancer is a complex disease that causes abnormal cell growth and spread. DNA mutations, chemical or environmental exposure, viral infections, chronic inflammation, hormone abnormalities, etc., are underlying factors that can cause cancer. Drug resistance and toxicity complicate cancer treatment. Additionally, the variability of cancer makes it difficult to establish universal treatment guidelines. Next-generation sequencing has made genetic testing inexpensive. This uncovers genetic mutations that can be treated with specialty drugs. AI (artificial intelligence), machine learning, biopsy, next-generation sequencing, and digital pathology provide personalized cancer treatment. This allows for patient-specific biological targets and cancer treatment. Monoclonal antibodies, CAR-T, and cancer vaccines are promising cancer treatments. Recent trial data incorporating these therapies have shown superiority in clinical outcomes and drug tolerability over conventional chemotherapies. Combinations of these therapies with new technology can change cancer treatment and help many. This review discusses the development and challenges of targeted therapies like monoclonal antibodies (mAbs), bispecific antibodies (BsAbs), bispecific T cell engagers (BiTEs), dual variable domain (DVD) antibodies, CAR-T therapy, cancer vaccines, oncolytic viruses, lipid nanoparticle-based mRNA cancer vaccines, and their clinical outcomes in various cancers. We will also study how artificial intelligence and machine learning help find new cancer treatment targets.

Short-course blinatumomab for refractory/relapse precursor B acute lymphoblastic leukemia in children

Objective

To evaluate the clinical efficacy and safety of a short course of blinatumomab in children with refractory or relapsed precursor B-cell acute lymphoblastic leukemia (R/R-BCP-ALL).

Methods

The clinical data of 33 R/R BCP-ALL children aged 0-18 years who underwent a short course of blinatumomab (14 days) between August 2021 and November 2022 were retrospectively collected and analyzed.

Results

Among 33 patients with BCP-ALL, 26 achieved complete remission (CR), with a total remission rate of 78.8% (26/33). The duration of remission was approximately 14 days. Of the 7 children without CR, 5 were still in remission at 28 days. In 11 patients with refractory disease and 22 with recurrence, the remission rates were 90.9% (10/11) and 72.7% (16/22), respectively. The overall survival (OS) rates of the 26 patients with CR and seven patients without CR were 96.1% and 57.1% (p = 0.002), respectively, and the disease-free survival (DFS) rates were 96.1% and 42.9% (p < 0.001), respectively. Among the 26 patients with CR, 15 underwent bridging hematopoietic stem cell transplantation (HSCT) and 11 did not receive HSCT; with OS rates of 93.3% and 100% (p = 0.40) and DFS rates of 93.3% and 100% (p = 0.400), respectively. The OS for all patients was 87.9% (29/33) and the DFS was 84.8% (28/33). There were 18 cases (54.5%) of cytokine release syndrome (CRS), 2 cases (6.1%) of severe CRS (all grade 3), 1 case (3.0%) of immune effector cell-associated neurotoxicity syndrome (ICANS), 0 cases (0%) of ICANS ≥ grade 3, and no deaths caused by treatment.

Conclusions

Short-term follow-up revealed a high R/R BCP-ALL remission rate in children treated with a short course of blinatumomab. The toxicity was low and controllable. No significant short-term survival benefits were observed after bridging HSCT with blinatumomab. In developing countries, a short course of blinatumomab can achieve satisfactory outcomes, while reducing household costs and saving medical resources.

Acute Lymphoblastic Leukemia Immunotherapy Treatment: Now, Next, and Beyond

Acute lymphoblastic leukemia (ALL) is a blood cancer that primarily affects children but also adults. It is due to the malignant proliferation of lymphoid precursor cells that invade the bone marrow and can spread to extramedullary sites. ALL is divided into B cell (85%) and T cell lineages (10 to 15%); rare cases are associated with the natural killer (NK) cell lineage (<1%). To date, the survival rate in children with ALL is excellent while in adults continues to be poor. Despite the therapeutic progress, there are subsets of patients that still have high relapse rates after chemotherapy or hematopoietic stem cell transplantation (HSCT) and an unsatisfactory cure rate. Hence, the identification of more effective and safer therapy choices represents a primary issue. In this review, we will discuss novel therapeutic options including bispecific antibodies, antibody-drug conjugates, chimeric antigen receptor (CAR)-based therapies, and other promising treatments for both pediatric and adult patients.

Pediatric Acute Lymphoblastic Leukemia Emerging Therapies-From Pathway to Target

Over the past 40 years, the 5-years-overall survival rate of pediatric cancer reached 75-80%, and for acute lymphoblastic leukemia (ALL), exceeded 90%. Leukemia continues to be a major cause of mortality and morbidity for specific patient populations, including infants, adolescents, and patients with high-risk genetic abnormalities. The future of leukemia treatment needs to count better on molecular therapies as well as immune and cellular therapy. Advances in the scientific interface have led naturally to advances in the treatment of childhood cancer. These discoveries have involved the recognition of the importance of chromosomal abnormalities, the amplification of the oncogenes, the aberration of tumor suppressor genes, as well as the dysregulation of cellular signaling and cell cycle control. Lately, novel therapies that have already proven efficient on relapsed/refractory ALL in adults are being evaluated in clinical trials for young patients. Tirosine kinase inhibitors are, by now, part of the standardized treatment of Ph+ALL pediatric patients, and Blinatumomab, with promising results in clinical trials, received both FDA and EMA approval for use in children. Moreover, other targeted therapies such as aurora-kinase inhibitors, MEK-inhibitors, and proteasome-inhibitors are involved in clinical trials that include pediatric patients. This is an overview of the novel leukemia therapies that have been developed starting from the molecular discoveries and those that have been applied in pediatric populations.

Blinatumomab Prior to CAR-T Cell Therapy-A Treatment Option Worth Consideration for High Disease Burden

The optimal bridging therapy before CAR-T cell infusion in pediatric relapsed or refractory B-cell precursor acute lymphoblastic leukemia (r/r BCP-ALL) still remains an open question. The administration of blinatumomab prior to CAR-T therapy is controversial since a potential loss of CD19+ target cells may negatively impact the activation, persistence, and, as a consequence, the efficacy of subsequently used CAR-T cells. Here, we report a single-center experience in seven children with chemorefractory BCP-ALL treated with blinatumomab before CAR-T cell therapy either to reduce disease burden before apheresis (six patients) or as a bridging therapy (two patients). All patients responded to blinatumomab except one. At the time of CAR-T cell infusion, all patients were in cytological complete remission (CR). Four patients had low positive PCR-MRD, and the remaining three were MRD-negative. All patients remained in CR at day +28 after CAR-T infusion, and six out of seven patients were MRD-negative. With a median follow-up of 497 days, four patients remain in CR and MRD-negative. Three children relapsed with CD19 negative disease: two of them died, and one, who previously did not respond to blinatumomab, was successfully rescued by stem cell transplant. To conclude, blinatumomab can effectively lower disease burden with fewer side effects than standard chemotherapeutics. Therefore, it may be a valid option for patients with high-disease burden prior to CAR-T cell therapy without clear evidence of compromising efficacy; however, further investigations are necessary.

Reliable Flow-Cytometric Approach for Minimal Residual Disease Monitoring in Patients with B-Cell Precursor Acute Lymphoblastic Leukemia after CD19-Targeted Therapy

We aimed to develop an antibody panel and data analysis algorithm for multicolor flow cytometry (MFC), which is a reliable method for minimal residual disease (MRD) detection in patients with B-cell precursor acute lymphoblastic leukemia (BCP-ALL) treated with CD19-directed therapy. The development of the approach, which was adapted for the case of possible CD19 loss, was based on the additional B-lineage marker expression data obtained from a study of primary BCP-ALL patients, an analysis of the immunophenotypic changes that occur during blinatumomab or CAR-T therapy, and an analysis of very early CD19-negative normal BCPs. We have developed a single-tube 11-color panel for MFC-MRD detection. CD22- and iCD79a-based primary B-lineage gating (preferably consecutive) was recommended. Based on patterns of antigen expression changes and the relative expansion of normal CD19-negative BCPs, guidelines for MFC data analysis and interpretation were established. The suggested approach was tested in comparison with the molecular techniques: IG/TR gene rearrangement detection by next-generation sequencing (NGS) and RQ-PCR for fusion-gene transcripts (FGTs). Qualitative concordance rates of 82.8% and 89.8% were obtained for NGS-MRD and FGT-MRD results, respectively. We have developed a sensitive and reliable approach that allows MFC-MRD monitoring after CD19-directed treatment, even in the case of possible CD19 loss.

One-point flow cytometric MRD measurement to identify children with excellent outcome after intermediate-risk BCP-ALL: results of the ALL-MB 2008 study

BACKGROUND

 Measurement of minimal residual disease (MRD) with multicolor flow cytometry (MFC) has become an important tool in childhood acute lymphoblastic leukemia (ALL), mainly to identify rapid responders and reduce their therapy intensity. Protocols of the Moscow-Berlin (MB) group use a comparatively low (for standard risk; SR) or moderate (for intermediate risk; ImR) treatment intensity from the onset, based on initial patient characteristics. Recently, we reported that 90% of SR patients-50% B cell precursor (BCP-ALL)-MFC-MRD negative at end of induction (EOI)-had 95% event-free survival (EFS).  METHODS: In the present study, we applied this method to children with initial ImR features.

RESULTS

 In study MB 2008, 1105 children-32% of BCP-ALL patients-were assigned to the ImR group. Of these, 227 were treated in clinics affiliated with MFC laboratories of the MB group network, and included in this MFC-MRD pilot study. A single-point MFC-MRD measurement at the EOI with the threshold of 0.01% identified 65% of patients-20% of all BCP-ALL patients-with EFS of 93.5%.

CONCLUSION

 Taking both studies together, the combination of clinical parameters and a one-point MRD measurement identifies 70% of BCP-ALL patients with an excellent outcome after low- or moderate-intensity therapy and avoids overtreatment of a significant proportion of patients.

B-lineage antigens that are useful to substitute CD19 for minimal residual disease monitoring in B cell precursor acute lymphoblastic leukemia after CD19 targeting

BACKGROUND

The potential loss of CD19 during targeted treatment of B cell precursor acute lymphoblastic leukemia (BCP-ALL) can hamper flow cytometric minimal residual disease (MRD) monitoring. In the current study, we present expression data for antigens that are candidates for CD19 substitution: surface CD22, CD24, CD10, and intracellular (i) CD79a.

METHODS

Bone marrow samples from 519 consecutive children (below 18 y.o.) with primary BCP-ALL were studied with a focus on expression of CD19, CD10, CD22, CD24, and iCD79a. As these antigens are planned to be used as substitutions for CD19 for primary B cell gating, only total expression on the leukemic population (≥95% cells) was considered appropriate.

RESULTS

It was found that each of these antigens is totally expressed in nearly 90% of patients. For each single marker, a subgroup of patients without complete positivity presented with BCP-ALL harboring diverse cytogenetic and molecular genetic aberrations. Based on expression data, we have developed algorithm of simultaneous application of these antigens for initial B-lineage compartment gating, that is applicable for nearly all patients after CD19 targeting.

CONCLUSION

We conclude that the addition of CD22, CD24, and iCD79a to the conventional antibody panel and their application together with CD10 allow for the identification of B-lineage compartment including residual tumor blasts, for MFC-MRD searching in virtually all patients with BCP-ALL after CD19-directed treatment.

Pediatric Hematopoietic Stem Cell Transplantation in Lithuania - 20 Years of Progress through Collaboration

Hematopoietic stem cell transplantation (HSCT) is a complex procedure that is curative for several fatal pediatric malignancies and non-malignant diseases. Despite its complexity, potential toxicity, and high costs HSCT has become a standard procedure worldwide for several decades. Pediatric HSCT programs encounter several specific challenges. The rarity and heterogeneity of primary diseases, result in an almost 10-fold inferior number of pediatric HSCT as compared to adults. In contrast to the adult programs, where autologous HSCT is more common, allogeneic HSCT (that is more complex) prevails in pediatric setting which is underpinned by a higher number of inborn disorders transplanted in early childhood.In Lithuania, the pediatric HSCT program (EBMT CIC* 508) was launched at Vilnius University Hospital Santaros Klinikos in February 2002. Currently, this is the only specialized pediatric HSCT center in Lithuania and in the Baltic countries. Since 2011 it is a reference center for Latvian children who need autologous or allogeneic transplantation.Here we summarize conference proceedings presented at the scientific event “Pediatric hematopoietic stem cell transplantation in Lithuania – 20 years of progress through collaboration”. The meeting held on September 22-23, 2022, in Vilnius and aimed at commemorating 20 years of the launch of the pediatric transplant program in Lithuania. The event pursued sharing the experience in the field of pediatric HSCT in the Baltic countries. Given a very small population in all three Baltic countries, Lithuania, Latvia, and Estonia face an additional challenge in maintaining sufficient transplant volume and gaining experience. Several distinguished speakers from USA, Denmark, Italy, Germany, Spain, UK and Ukraine shared their expertise in the field and emphasized the crucial role of national and international collaboration to achieve progress in the management of this very rare and complex procedure that offers cure for otherwise fatal pediatric conditions.

Immunotherapy for Pediatric Acute Lymphoblastic Leukemia: Recent Advances and Future Perspectives

Pediatric acute lymphoblastic leukemia (ALL) is the most common subtype of childhood leukemia, which is characterized by the abnormal proliferation and accumulation of immature lymphoid cell in the bone marrow. Although the long-term survival rate for pediatric ALL has made significant progress over years with the development of contemporary therapeutic regimens, patients are still suffered from relapse, leading to an unsatisfactory outcome. Since the immune system played an important role in the progression and relapse of ALL, immunotherapy including bispecific T-cell engagers and chimeric antigen receptor T cells has been demonstrated to be capable of enhancing the immune response in pediatric patients with refractory or relapsed B-cell ALL, and improving the cure rate of the disease and patients’ quality of life, thus receiving the authorization for market. Nevertheless, the resistance and toxicities associated with the current immunotherapy remains a huge challenge. Novel therapeutic options to overcome the above disadvantages should be further explored. In this review, we will thoroughly discuss the emerging immunotherapeutics for the treatment of pediatric ALL, as well as side-effects and new development.

Blinatumomab as a Bridge Therapy for Hematopoietic Stem Cell Transplantation in Pediatric Refractory/Relapsed Acute Lymphoblastic Leukemia

Simple Summary

Immunotherapies are modern treatment modalities, giving hope for improvements of frozen cure rates in many childhood malignancies. More intensive cytotoxic chemotherapy cycles didn’t improve cure rates, only increase number of adverse events. Blinatumomab, a bispecific CD3/CD19 antibody construct, has been successfully used in relapsed/refractory r/r B-cell precursor ALL (BCP-ALL) as a bridge to hematopoietic stem cell transplantation (HSCT). We retrospectively assessed the efficacy and toxicity of blinatumomab in 13 children with r/r BCP-ALL. The response rate in our cohort of patients was 85%, with subsequent feasible HSCT in 11 out of 13 children. Although our study had some limitations with regard to its retrospective design and limited patient population, it clearly showed blinatumomab as not only a feasible but also an effective therapeutic option in pretreated children with r/r BCP-ALL, with a tolerable toxicity profile, paving the way for an HSCT procedure. To date, this is the first retrospective study from Poland on efficacy and toxicity of blinatumomab therapy in children with r/r ALL.

Abstract

Despite the progress that has been made in recent decades in the treatment of pediatric acute leukemias, e.g., converting acute lymphoblastic leukemia (ALL) from a fatal to a highly curable disease, 15–20% of children still relapse. Blinatumomab, a bispecific CD3/CD19 antibody construct, has been successfully used in relapsed/refractory r/r B-cell precursor ALL (BCP-ALL) as a bridge to hematopoietic stem cell transplantation (HSCT). We retrospectively assessed the efficacy and toxicity of blinatumomab in 13 children with r/r BCP-ALL. Between 2017 and 2021, thirteen children, aged 1–18 years, with r/r BCP-ALL were treated with blinatumomab. Two patients were administered blinatumomab for refractory relapse without complete remission (CR), one due to primary refractory disease, and ten patients were in CR with minimal residual disease (MRD) ≥ 10⁻³. The response rate in our cohort of patients was 85%, with subsequent feasible HSCT in 11 out of 13 children. Ten children reached MRD negativity after the first blinatumomab administration. The three-year OS for the study patients was 85% (Mantel–Cox, p < 0.001) and median follow-up was 24.5 (range: 1–47). All responders proceeded to HSCT and are alive in CR, and MRD negative. Although our study had some limitations with regard to its retrospective design and limited patient population, it clearly showed blinatumomab as not only a feasible but also an effective therapeutic option in pretreated children with r/r BCP-ALL, with a tolerable toxicity profile, paving the way for an HSCT procedure.

Blinatumomab in Children and Adolescents with Relapsed/Refractory B Cell Precursor Acute Lymphoblastic Leukemia: A Real-Life Multicenter Retrospective Study in Seven AIEOP (Associazione Italiana di Ematologia e Oncologia Pediatrica) Centers

Five-year event-free survival in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL) currently exceeds 80-85%. However, 15-20% of patients still experience a relapsed/refractory disease. From 1 January 2015 to 31 December 2020, thirty-nine patients, 0-21 years old with r/r BCP-ALL were treated with blinatumomab with the aim of inducing remission (n = 13) or reducing MRD levels (n = 26) in the frame of different multiagent chemotherapy schedules, in seven AIEOP centers. Patients were treated in compassionate and/or off-label settings and were not enrolled in any controlled clinical trials. Treatment was well tolerated; 22 (56.4%) patients reported adverse events (AE) on a total of 46 events registered, of which 27 (58.7%) were ≤2 grade according to CTCAE. Neurological AEs were 18 (39.1%); only two patients required transient blinatumomab discontinuation. Complete remission (CR) rate was 46% for the 13 patients treated with ≥5% blasts and 81% PCR/FC MRD negativity in the 26 patients with blasts < 5%. Median relapse-free survival was 33.4 months (95% CI; 7.5-59.3); median overall survival was not reached over a mean follow-up of 16 months. In our study, as in other real-life experiences, blinatumomab proved to be effective and well-tolerated, able to induce a high rate of CR and MRD negativity.

Blinatumomab for treating pediatric B-lineage acute lymphoblastic leukemia: A retrospective real-world study

OBJECTIVES

Blinatumomab was shown to be safe and effective for consolidation therapy in B-cell acute lymphoblastic leukemia (B-ALL). This study aimed to investigate the effectiveness and safety of blinatumomab in pediatric B-ALL patients in a real-world setting.

METHODS

This was a retrospective, observational study that included patients who initiated blinatumomab treatment between October 1, 2020 and June 20, 2022. Patients with B-ALL diagnosis, age below 18 years, and at least one blinatumomab treatment cycle were included. Treatment-related toxicities were assessed.

RESULT

Totally 23 pediatric patients were included in this study, with a median age of 6 years (range, 2 to 11 years). Blinatumomab therapy was applied for MRD-positive (disease ≥0.01%, n = 3) or chemotherapy-ineligible (n = 20) B-ALL cases. The median follow-up time was 9 months, and all evaluable patients achieved complete molecular remission with undetectable MRD. Four relapsed B-ALL cases proceeded to hematopoietic stem cell transplantation (HSCT) without further bridging therapy, while the others underwent maintenance chemotherapy after blinatumomab treatment. Grade ≥3 febrile neutropenia, white blood cell decrease and seizure were observed in 57%, 48% and 4.3% of patients, respectively. One case discontinued therapy due to neurologic toxicities. Elevated cytokine levels were observed in 4 patients. In all 23 patients, increased T-cell and low B-cell counts (<10/μl) were detected during blinatumomab therapy.

CONCLUSION

These encouraging results suggest blinatumomab in pediatric B-ALL patients with MRD⁺ or chemotherapy-related toxicities is effective and safe in the short run, although long-term follow-up is still needed.