Efficacy and Safety of Blinatumomab for the Treatment of Relapsed/Refractory Acute Lymphoblastic Leukemia: A Systemic Review and Meta-Analysis

Impact of Minimal Residual Diseases Status and Depth of Response on Survival Outcomes in Blinatumomab-Treated Acute Lymphoblastic Leukemia: A Systematic Review and Meta-Analysis

OBJECTIVES

Acute lymphoblastic leukemia (ALL) is a common hematological malignancy that occurs due to blockage of B-lymphocyte maturation at an early stage of development and differentiation. The Food and Drug Administration approved blinotumomab to manage relapsed/refractory ALL (R/R ALL). This review aimed to determine the comparative efficacy of blinatumomab in treating R/R ALL.

METHODS

Two reviewers searched 3 electronic databases, PubMed, ScienceDirect, and CENTRAL, for all relevant articles published until July 2024. All the articles that met the inclusion criteria were included in the review.

RESULTS

Four hundred thirty-seven articles were found from the electronic search; however, only 21 articles met the inclusion criteria. A pooled analysis of the outcomes found that blinatumomab resulted in an improvement in both the OS (HR: 0.65; 95% CI: 0.51, 0.82; P =0.0003) and the DFS (HR: 0.57; 95% CI: 0.41, 0.80; P =0.001). Further analysis showed that the CR rate and MRD response of ALL patients to blinatumomab was 51.6% (95% CI: 48.5%, 54.6%; P =0.319) and 64.6% (95% CI: 53.4%, 74.3%; P =0.011), respectively. The safety analysis indicated that the incidence of serious AEs was comparable in patients receiving blinotumomab and those receiving standard chemotherapy (OR: 1.34; 95% CI; 0.91, 1.97; P =0.14).

CONCLUSIONS

The findings show that blinatumomab is superior to standard chemotherapy in improving the OS and DFS of patients with R/R ALL. Furthermore, it has a more favorable safety profile, making it an effective alternative to conventional chemotherapy for managing R/R ALL.

How I Investigate Measurable Residual Disease in B-Cell Precursor Acute Lymphoblastic Leukemia After Therapy With Bi-Specific Monoclonal Antibodies and 19CAR-T Cells

INTRODUCTION

Measurable residual disease (MRD) in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) following anti-CD19 targeted therapies requires specific strategies to identify residual blast cells due to loss or reduced CD19 expression that makes it inconsistent as a primitive marker for B-cell gating.

OBJECTIVE

Due to the increased access of BCP-ALL patients to therapies with CD3/CD19 bispecific T-cell engagers (BiTe) and CD19-targeted chimeric antigen receptor T-Cell (CAR-T), it is essential that flow cytometry laboratories are prepared to evaluate therapeutic responses.

MATERIAL AND METHODS

Here, validated strategies for MRD detection in the context of anti-CD19 therapies are described, accessible to flow cytometry laboratories according to their different facilities. The paper includes an 8-color flow cytometry (FC) strategy for BCP-ALL MRD based on alternative gating without the use of additional markers (Euroflow protocol), as well as other strategies using alternative markers to CD19, comprising 2 protocols using 8 colors, one using 10 colors and another 14 colors/15 markers.

CONCLUSION

Different strategies are needed to detect MRD without using CD19 for B-cell population gating after CD19-targeted therapies. However, it is essential that validated protocols are used according to the available resources to ensure reliable results for clinical decision-making.

The role of blinatumomab in adult acute B lymphoblastic leukaemia

Blinatumomab is a CD19 × CD3-directed bispecific T-cell engager that has become an essential backbone of acute B lymphoblastic leukaemia (BCP-ALL) treatment. It is used in relapsed/refractory disease, minimal residual disease (MRD), as well as in first-line treatment. Blinatumomab is particularly effective in MRD-positive BCP-ALL, inducing a high rate of deep molecular response, with very good overall tolerability. Very promising data are reported for the addition of blinatumomab to first-line therapy. This review focusses on new aspects of blinatumomab treatment in Philadelphia-negative BCP-ALL treatment in adult patients, including MRD-positive and relapsed/refractory disease, as well as reviewing recent clinical trials implementing blinatumomab into first-line therapy of BCP-ALL treatment.

Diagnosis and management of bispecific T cell-engaging antibody toxicity: A primer for emergency physicians

BACKGROUND

T-cell-engaging bispecific antibodies (BsAbs) are a newer type of immunotherapy designed to boost T-cell cytotoxicity. They are increasingly used in cancer treatment, with drugs currently being tested and authorized for treating both liquid and solid tumors. It's becoming more likely that emergency physicians and other acute care practitioners will treat patients experiencing adverse events related to bispecific antibodies, as these drugs are regularly given in the outpatient setting. Currently, BsAb-associated side effects are not routinely taught to Emergency Medicine residents, and a paucity of literature exists to guide currently practicing Emergency Medicine physicians and other acute care practitioners about these medications.

OBJECTIVE OF THE REVIEW

This review was written by emergency medicine physicians in collaboration with oncologists who routinely administer BsAbs to provide guidelines and an overview on diagnosis, treatment, and management strategies for adverse events related to bispecific antibodies.

DISCUSSION

Side effects related to BsAbs require a multidisciplinary treatment approach ideally with oncologists notified early when an adverse event is suspected. Symptom presentation is subtle with BsAb toxicity and the main adverse events to consider working up are cytokine release syndrome, immune effector cell neurotoxicity, and infection. The article also discusses unique side effects specific to FDA-approved drugs to treat leukemia, multiple myeloma, lymphoma, lung cancer, and melanoma given that this drug class has heterogeneous receptor-specific side effects.

Efficacy and safety of blinatumomab for the treatment of patients relapsing after allogeneic hematopoietic cell transplantation: a systemic review and meta-analysis

OBJECTIVE

We aim to evaluate the efficacy and safety of blinatumomab for the treatment of post-transplant relapse patients with acute lymphoblastic leukemia (ALL).

METHODS

The search was conducted using several databases including the PubMed, Cochrane Library, Embase, Chinese National Knowledge Infrastructure (CNKI) and Wanfang Data Knowledge Service Platform to collect clinical studies related to blinatumomab. The primary outcome measures were complete remission (CR), 1-year overall survival (OS), 2-year OS, median OS and adverse events (AEs). Grade ≥3 AEs were mainly analyzed for safety, including anemia, thrombocytopenia, neutropenia, encephalopathy, peripheral paresthesia, tremor and cytokine release syndrome (CRS).

RESULTS

A total of 7 studies, involving a total of 292 patients were included in the analysis. The analysis results showed CR rate of 48%, 1-year OS rate of 40% 2-year OS rate of 21%, median OS 7.47. For safety analysis, the incidence of grade ≥3 AEs, including the incidence of grade ≥3 anemic toxicity was 13% , the incidence of grade ≥3 thrombocytopenia toxicity was 7% , the incidence of grade ≥3 neutropenia toxicity 24%, the incidence of grade ≥3 encephalopathic toxicity was 4% , the incidence of grade ≥3 peripheral paresthesia toxicity 4%, the incidence of grade ≥3 tremor toxicity 8% , the incidence of grade ≥3 CRS toxicity was 4%.

CONCLUSION

Blinatumomab may be a safe and an effective treatment approach for post-transplant relapse patients with ALL, but its long-term efficacy is still a big challenge. In regard to Regarding AEs, serious CRS and neurological events were infrequent and manageable.

Engineered oncolytic virus expressing B7H3-targeting BiTE enhances antitumor T-cell immune response

BACKGROUND

Bispecific T-cell engagers (BiTEs) are recombinant bispecific proteins designed to stimulate polyclonal T-cell immunity. In recent years, B7H3, a pan-cancer antigen, has been considered a promising target for future immunotherapy. However, the B7H3-targeting BiTE faces the challenge of systemic toxicity. Oncolytic viruses (OVs) represent a new class of cancer immunotherapeutics and serve as an appropriate platform for locoregional delivery of therapeutic genes. In this study, we designed an oncolytic adenovirus (OAd) encoding BiTE targeting human B7H3. We hypothesized that OVs encoding B7H3 BiTE deliver this molecule persistently to the tumor site while mediating polyclonal T-cell activation and redirecting it to tumor cells.

METHODS

B7H3-targeting BiTE was constructed by linking a single-chain variable fragment (scFv) that recognizes human B7H3 to an scFv that recognizes human CD3. B7H3 BiTE was inserted into OAd to construct OAd-B7H3-BiTE. The function of the OV-delivered B7H3 BiTE was detected via co-culturing B7H3+ target cells and peripheral blood mononuclear cells. A humanized immune system mouse model was used to evaluate the therapeutic effects in vivo.

RESULTS

B7H3 is highly expressed in a high proportion of human malignancies. OV-delivered BiTEs bind to T cells and target cells. We observed a series of phenomena reflecting T-cell activation induced by OAd-B7H3-BiTE, including cell clustering, cell size, activation markers, cytokine secretion, and proliferation. Furthermore, T-cell activation was mirrored by the corresponding cytotoxicity against B7H3+ tumor cells. In vivo, B7H3 BiTE was persistently expressed in tumors and enhanced the antitumor T-cell immune response.

CONCLUSIONS

Using an OV for the local expression of B7H3 BiTE maximizes the local concentration of BiTE while reducing systemic exposure. OV also provides a relatively "hot" T-cell immune environment for the function of BiTE. Because of its capacity to activate polyclonal T cells, BiTE has the potential to redirect virus-specific T cells to tumors. Our study provides new opportunities for the exploitation of B7H3-BiTE-armed OVs as therapeutic agents for the treatment of B7H3-positive malignancies.

Hydrophilic biomaterials: From crosslinked and self-assembled hydrogels to polymer-drug conjugates and drug-free macromolecular therapeutics

This "Magnum Opus" accentuates my lifelong belief that the future of science is in the interdisciplinary approach to hypotheses formulation and problem solving. Inspired by the invention of hydrogels and soft contact lenses by my mentors, my six decades of research have continuously proceeded from the synthesis of biocompatible hydrogels to the development of polymer-drug conjugates, then generation of drug-free macromolecular therapeutics (DFMT) and finally to multi-antigen T cell hybridizers (MATCH). This interdisciplinary journey was inspiring; the lifetime feeling that one is a beginner in some aspects of the research is a driving force that keeps the enthusiasm high. Also, I wanted to illustrate that systematic research in one wide area can be a life-time effort without the need to jump to areas that are temporarily en-vogue. In addition to generating general scientific knowledge, hydrogels from my laboratory have been transferred to the clinic, polymer-drug conjugates to clinical trials, and drug-free macromolecular systems have an excellent potential for personalizing patient therapies. There is a limit to life but no limit to imagination. I anticipate that systematic basic research will contribute to the expansion of our knowledge and create a foundation for the design of new paradigms based on the comprehension of mechanisms of physiological processes. The emerging novel platform technologies in biomaterial-based devices and implants as well as in personalized nanomedicines will ultimately impact clinical practice.

Supportive care measures for bispecific T-cell engager therapies in haematological malignancies

PURPOSE OF REVIEW

Bispecific T-cell engager (TCE) therapies are revolutionising the treatment of several haematological malignancies, including B-cell acute lymphoblastic leukaemia, various subtypes of B-cell non-Hodgkin lymphoma, and multiple myeloma. Due to their unique mode of action in activating endogenous T cells, they are associated with several important early side effects, including cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome. In addition, TCEs can cause target-specific toxicities and carry a significant risk of infection.

RECENT FINDINGS

Currently, supportive care measures for TCEs have largely been inferred from other T-cell therapies, such as CAR-T (chimeric antigen receptor) therapy. Further research into TCE-specific supportive care measures is needed to improve the tolerability of these therapies for patients. A key question moving forward is understanding how to predict and minimise early toxicity (cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome). Associated infection risk is a significant cause of patient morbidity, therefore a better understanding of how to optimise TCE-dosing and prophylactic measures, such as intravenous immunoglobulin and antimicrobials, will be crucial to achieving an improved balance of toxicity and efficacy. Enabling early outpatient delivery of these therapies to select patients at lower risk of toxicity may also help to improve patient experience and quality of life.

SUMMARY

Here we review up-to-date guidance and literature on existing supportive care measures for bispecific TCE therapy-related toxicities. We highlight both unique and serious side effects of TCE therapies that require improved management strategies to enable more patients to benefit from these efficacious drugs.

The Evolving Landscape of Flowcytometric Minimal Residual Disease Monitoring in B-Cell Precursor Acute Lymphoblastic Leukemia

Detection of minimal residual disease (MRD) is a major independent prognostic marker in the clinical management of pediatric and adult B-cell precursor Acute Lymphoblastic Leukemia (BCP-ALL), and risk stratification nowadays heavily relies on MRD diagnostics. MRD can be detected using flow cytometry based on aberrant expression of markers (antigens) during malignant B-cell maturation. Recent advances highlight the significance of novel markers (e.g., CD58, CD81, CD304, CD73, CD66c, and CD123), improving MRD identification. Second and next-generation flow cytometry, such as the EuroFlow consortium's eight-color protocol, can achieve sensitivities down to 10-5 (comparable with the PCR-based method) if sufficient cells are acquired. The introduction of targeted therapies (especially those targeting CD19, such as blinatumomab or CAR-T19) introduces several challenges for flow cytometric MRD analysis, such as the occurrence of CD19-negative relapses. Therefore, innovative flow cytometry panels, including alternative B-cell markers (e.g., CD22 and CD24), have been designed. (Semi-)automated MRD assessment, employing machine learning algorithms and clustering tools, shows promise but does not yet allow robust and sensitive automated analysis of MRD. Future directions involve integrating artificial intelligence, further automation, and exploring multicolor spectral flow cytometry to standardize MRD assessment and enhance diagnostic and prognostic robustness of MRD diagnostics in BCP-ALL.

Neurologic Complications of Cancer Immunotherapy

Immunotherapy has revolutionized cancer treatment over the past decade. As it is increasingly introduced into routine clinical practice, immune-related complications have become more frequent. Accurate diagnosis and treatment are essential, with the goal of reduced patient morbidity. This review aims to discuss the various clinical manifestations, diagnosis, treatments, and prognosis of neurologic complications associated with the use of immune checkpoint inhibitors, adoptive T-cell therapies, and T-cell redirecting therapies. We also outline a suggested clinical approach related to the clinical use of these agents.