Brentuximab vedotin in T-cell lymphoma

Increased Non-Relapse Mortality in Older People With Allogeneic Hematopoietic Stem Cell Transplantation Using Fludarabine and Myeloablative Dose of Busulfan-Based Regimen

Fludarabine and myeloablative busulfan (FluBu4) in allogeneic hematopoietic stem cell transplantation (HSCT) for older people have not been adequately examined. This retrospective study analyzed data from a large-scale, nationwide database in Japan. Adult patients (> 15 years old, y/o) who received their first HSCT with FluBu4 for hematological malignancies were included. They were categorized into the younger (< 60 y/o, N = 1295) and the older group (≥ 60 y/o, N = 993). The 3-year overall survival (OS) rate after HSCT was significantly worse in the older group than in the other (p < 0.01, 39.9% vs. 48.5%). The 3-year non-relapse mortality (NRM) was significantly higher in the older group than in the other (p < 0.01, 30.9% vs. 23.0%), and the 3-year cumulative incidence of relapse was comparable between them. According to the multivariate analysis, age ≥ 60 years was significantly associated with poor OS and high NRM. In a subgroup analysis of the older group, the use of additional chemotherapeutic drugs to FluBu4 was significantly associated with poor OS and high NRM. Total body irradiation was significantly associated with high NRM and 1-year incidence of sinusoidal obstruction syndrome but not with OS. Thus, FluBu4 should be used with caution in older people.

Fludarabine Plus Myeloablative Dose of Busulfan Regimen Was Associated with High Nonrelapse Mortality in Allogeneic Hematopoietic Stem Cell Transplantation for Malignant Lymphoma: A Propensity Score-Matched Comparison Study with Fludarabine Plus High-Dose Melphalan

In recent years, there have been notable advancements in the treatment of malignant lymphoma. However, a certain percentage of patients are unlikely to achieve a cure through chemotherapy alone. Therefore, allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a crucial curative treatment for malignant lymphoma. FluBu4, comprising fludarabine (Flu) combined with a myeloablative dose of intravenous busulfan (Bu; 12.8 mg/kg in total), is a widely used conditioning regimen for allo-HSCT, but its usefulness in malignant lymphoma (ML) has not been fully investigated. The objective of this study was to evaluate the efficacy and safety of FluBu4 in allo-HSCT for lymphoma by comparing the outcomes of two conditioning regimens: FluBu4 and FluMel140. We used a Japanese national database from the Transplant Registry Unified Management Program to retrospectively analyze the first allo-HSCT for ML in patients aged ≥16 years. Allo-HSCT cases treated with posttransplant cyclophosphamide were excluded. Two groups, namely FluBu4 and FluMel140 were selected by propensity score matching (PSM) with a case ratio of 1:2. From 921 cases, 113 were selected by PSM for the FluBu4 group and 226 for the FluMel140 group. The median age was 54 (19 to 68) years, the median observation period of survivors was 33.8 months, and 145 (42.7%) had a history of autologous HSCT. There were no significant differences in patients' backgrounds between the two groups after PSM. Three-year overall survival (OS) was significantly worse for FluBu4 than for FluMel140 (28.0% versus 48.6%; P < .01). The 3-year cumulative relapse rate was comparable for FluBu4 and FluMel140 (40.1% versus 38.5%; P = .65). However, 3-year nonrelapse mortality was significantly higher for FluBu4 than for FluMel140 (35.3% versus 22.5%; P = .02). There was no significant difference between the two treatment groups in the cumulative incidence of acute graft-versus-host disease (aGVHD) at day 100 after allo-HSCT and the 3-year cumulative incidence of chronic GVHD. While the common and major cause of death was the relapse of lymphoma, aGVHD, and noninfectious lung complications were observed more frequently with FluBu4 than with FluMel140. One-year cumulative incidence of interstitial pneumonia was significantly higher for FluBu4 than for FluMel140 (5.3% versus 0.4%; P = .03). FluBu4 use was associated with worse nonrelapse mortality (NRM) and OS in allo-HSCT for ML compared with FluBu4 and FluMel140 adjusted by PSM. Patients treated with FluBu4 had a higher incidence of noninfectious pulmonary complications and an increased number of associated deaths. A higher rate of NRM in the patients treated with FluBu4 was particularly evident in patients aged ≥60, and its use should be avoided in this patient population.

Monoclonal antibodies - A repertoire of therapeutics

Antibodies are a class of biomolecules armed with extraordinary diversity, unmatched in the biological world by any other class of molecules. This characteristic feature equips antibodies to recognize, bind, and eliminate an infinite number of pathogens/antigens facilitated by their effector functions. The repertoire of natural binding specificities of antibodies (Abs) is greater than the calculated estimate of ∼1012 in humans, as a naive, single antigen-binding site may bind more than one antigen employing the plasticity in antigen-antibody interactions, potentiating Abs to fight infinite pathogenic insults and restrict the development of cancers. Additionally, advanced technological interventions, by allowing manipulation of the germline and acquired specificities of human/animal immunoglobulins (Ig) have contributed immensely to broaden their existing repertoire and scope of clinical applications. The available natural repertoire of Ig and Ig-like molecules in other animals, e.g., mice, horses, cows, pigs, rabbits, camels, llamas, etc., further diversified the source of unique antigen-binding specificities. The recombinant DNA technology, in association with hybridoma , transgenic, and phage display technologies, has helped create a parallel repertoire of unique antibody molecules [animal Abs, camelid heavy chain Abs (hcAbs), chimeric Abs, chimeric hcAbs, humanized Abs, humanized nanobody (Nb)-hcAbs, human Abs, etc.], monoclonal Ab (mAb) derived fragments [antigen-binding-fragment (Fab), single-chain-variable-fragment (scFv), variable-fragement (Fv), single-variable-domain of hcAbs (VHH), bispecific scFv, diabodies, triabodies, intrabodies, bispecific Fabs, tri-specific Fabs, etc.), and immunoconjugates generated by fusing/conjugating mAb fragments with enzyme, toxin, prodrug etc., molecules. The current chapter provides a detailed description of the natural and engineered antibody repertoires and discusses various strategies using which these molecules are being inducted as novel immunotherapeutics for treating a significant number of human diseases.

Therapeutic potential of brentuximab vedotin in breast cancer and lymphoma via targeted apoptosis and gene regulation

This study was designed to assess the effect of brentuximab vedotin on several breast cancer cell lines in terms of promoting apoptosis and managing cancer progression. Additionally, the study investigated the potential of repurposing this drug for new therapeutic reasons, beyond its original indications. The study evaluates the cytotoxic effects of Brentuximab vedotin across five cell lines: normal human skin fibroblasts (HSF), three breast cancer cell lines (MCF-7, MDA-MB-231, and T-47D), and histiocytic lymphoma (U-937). Brentuximab treatment was administered at four time points (0, 24, 48, and 72 h), with cell viability assessed at each interval. HSF cells, serving as controls, exhibited minimal viability loss (above 70%), indicating limited toxicity in normal fibroblasts. In contrast, MCF-7 and MDA-MB-231 cells demonstrated time-dependent reductions in viability, with a pronounced decline by 72 h, suggesting Brentuximab's efficacy in both ER-positive and triple-negative breast cancer. T-47D cells also showed decreased viability, though at a slower rate. U-937 cells exhibited the most substantial reduction, highlighting Brentuximab's potent activity against hematologic malignancies. Wound healing assays further revealed that Brentuximab significantly impaired the migration and healing capacity of cancer cells compared to untreated controls. Additionally, cell cycle analysis indicated G2/M phase arrest in cancer cells, particularly in MCF-7 and MDA-MB-231, while HSF cells remained largely unaffected. Apoptosis detection confirmed Brentuximab-induced cell death, with significant increases in late apoptosis in cancer lines, especially by 72 h. Gene expression analysis revealed upregulation of pro-apoptotic genes (BAX, Caspase 3, and Caspase 9) in cancer cells, alongside a decrease in anti-apoptotic BCL-2 expression. These findings suggest Brentuximab's selective cytotoxicity against cancer cells and its potential as an effective therapeutic agent, particularly in breast cancer and histiocytic lymphoma.

Antibody drug conjugates in the clinic

Antibody-drug conjugates (ADCs), chemotherapeutic agents conjugated to an antibody to enhance their targeted delivery to tumors, represent a significant advancement in cancer therapy. ADCs combine the precise targeting capabilities of antibodies and the potent cell-killing effects of chemotherapy, allowing for enhanced cytotoxicity to tumors while minimizing damage to healthy tissues. Here, we provide an overview of the current clinical landscape of ADCs, highlighting 11 U.S. Food and Drug Administration (FDA)-approved products and discussing over 500 active clinical trials investigating newer ADCs. We also discuss some key challenges associated with the clinical translation of ADCs and highlight emerging strategies to overcome these hurdles. Our discussions will provide useful guidelines for the future development of safer and more effective ADCs for a broader range of indications.

Synthesis and Reactivity of Masked Organic Sulfates

Nature offers a variety of structurally unique, sulfated endobiotics including sulfated glycosaminoglycans, sulfated tyrosine peptides, sulfated steroids/bile acids/catecholamines. Sulfated molecules display a large number of biological activities including antithrombotic, antimicrobial, anticancer, anti-inflammatory, and others, which arise from modulation of intracellular signaling and enhanced in vivo retention of certain hormones. These characteristics position sulfated molecules very favorably as drug-like agents. However, few have reached the clinic. Major hurdles exist in realizing sulfated molecules as drugs. This state-of-the-art has been transformed through recent works on the development of sulfate masking technologies for both alkyl (sulfated carbohydrates, sulfated steroids) and aryl (sTyr-bearing peptides/proteins, sulfated flavonoids) sulfates. This review compiles the literature on different strategies implemented for different types of sulfate groups. Starting from early efforts in protection of sulfate groups to the design of newer SuFEx, trichloroethyl, and gem-dimethyl-based protection technologies, this review presents the evolution and application of concepts in realizing highly diverse, sulfated molecules as candidate drugs and/or prodrugs. Overall, the newer strategies for sulfate masking and demasking are likely to greatly enhance the design and development of sulfated molecules as non-toxic drugs of the future.

Pharmacovigilance study of the association between peripheral neuropathy and antibody-drug conjugates using the FDA adverse event reporting system

Antibody-drug conjugates (ADCs) are among the fastest-growing classes of anticancer drugs, making it crucial to evaluate their potential for causing peripheral neuropathy. We analyzed data from the FAERS database (January 1, 2014, to June 30, 2023) using disproportionality and Bayesian methods. We identified 3076 cases of ADC-associated peripheral neuropathy. Our study revealed significant signals for all ADCs (ROR 1.82, 95% CI 1.76-1.89). ADCs with tubulin-binding payloads showed significant peripheral neuropathy signals (ROR 2.31, 95% CI 2.23-2.40), whereas those with DNA-targeting (ROR 0.48, 95% CI 0.39-0.59) and topoisomerase 1 inhibitor (ROR 0.56, 95% CI 0.48-0.66) payloads exhibited non-significant signals. Signals for peripheral sensory neuropathy were 4.83, 2.44, 2.74, and 2.21 (calculated based on IC025) for brentuximab vedotin, trastuzumab emtansine, enfortumab vedotin, and polatuzumab vedotin, while signals for peripheral motor neuropathy were 5.31, 0.34, 2.27, and 0.03, respectively. The median time to onset for all ADCs was 127 days (interquartile range 40-457). Tisotumab vedotin had the highest hospitalization rate at 26.67%, followed by brentuximab vedotin at 25.5%. Trastuzumab emtansine had the highest mortality rate ,with 80 deaths (11.96%) among 669 cases. Based on FAERS database, only ADCs with tubulin-binding payloads exhibited significant peripheral neuropathy signals. Brentuximab vedotin and enfortumab vedotin showed similar profiles for peripheral sensory neuropathy and motor neuropathy. Given the delayed time to onset and potentially poor outcomes, ADC-related peripheral neuropathy warrants significant attention.

New and developing first line pharmacotherapies for treating non-Hodgkin lymphoma

INTRODUCTION

Non-Hodgkin lymphomas (NHLs) encompass a wide range of diseases from precancerous states such as monoclonal B-cell lymphocytosis to the rapidly growing Burkitt lymphoma. In 2022, we witnessed two new classifications for these malignant lymphoid tumors: The World Health Organization (WHO) 5th edition Classification of Haematolymphoid Tumours and the International Consensus Classification of Mature Lymphoid Neoplasms (ICC).

AREAS COVERED

Given our improved understanding of the mechanisms underlying lymphomagenesis at the molecular level, several novel agents have been or are being actively developed, including targeted therapies and immunotherapies. Therefore, this review features new and developing first-line pharmacotherapies in NHL. It is organized by the mechanism of action of the drug with the relevant key trials highlighted.

EXPERT OPINION

We provide an overview of the development of curative combination chemotherapies for lymphomas, and then discuss the importance of working on a unified classification for these tumors. We discuss resistance to targeted therapies, particularly with the continuous use of Bruton tyrosine kinase inhibitors, how to sequence T-cell therapies (bispecific T-cell engagers and chimeric antigen receptor therapy), and the impact of financial toxicity. We also review possible strategies to increase cure rates at lower costs, with less toxicity, and while promoting global health.

Antibody-drug conjugates in cancer therapy: mechanisms and clinical studies

Antibody-drug conjugates (ADCs) consist of monoclonal antibodies that target tumor cells and cytotoxic drugs linked through linkers. By leveraging antibodies' targeting properties, ADCs deliver cytotoxic drugs into tumor cells via endocytosis after identifying the tumor antigen. This precise method aims to kill tumor cells selectively while minimizing harm to normal cells, offering safe and effective therapeutic benefits. Recent years have seen significant progress in antitumor treatment with ADC development, providing patients with new and potent treatment options. With over 300 ADCs explored for various tumor indications and some already approved for clinical use, challenges such as resistance due to factors like antigen expression, ADC processing, and payload have emerged. This review aims to outline the history of ADC development, their structure, mechanism of action, recent composition advancements, target selection, completed and ongoing clinical trials, resistance mechanisms, and intervention strategies. Additionally, it will delve into the potential of ADCs with novel markers, linkers, payloads, and innovative action mechanisms to enhance cancer treatment options. The evolution of ADCs has also led to the emergence of combination therapy as a new therapeutic approach to improve drug efficacy.

Updates on the mechanisms of toxicities associated with monoclonal antibodies targeting growth factor signaling and immune cells in cancer

Monoclonal antibody (mAb)-based immunotherapy currently is considered to be an optimal therapeutic approach to cancer treatment, either in combination with surgery, radiation, and/or chemotherapy or alone. Various solid tumors and hematological malignancies have been characterized by distinct molecular targets, which could be utilized as innovative anticancer agents. Notably, receptor tyrosine kinases, including HER2, EGFR, VEGFR, and PDGFR, which act as receptors for growth factors, serve as crucial target proteins, expanding their role in the cancer therapeutic market. In contrast to conventional anticancer agents that directly target cancer cells, the advent of immunotherapy introduces novel approaches, such as immune checkpoint blockers (ICBs) and mAbs targeting surface antigens on immune cells in hematological malignancies and lymphomas. While these immunotherapies have mitigated the acquired resistance observed in traditional targeted therapies, they also exhibit diverse toxicities. Herein, this review focuses on describing the well-established toxicities and newly proposed mechanisms of monoclonal antibody toxicity in recent studies. Understanding these molecular mechanisms is indispensable to overcoming the limitations of mAbs-based therapies, facilitating the development of innovative anticancer agents, and uncovering novel indications for cancer treatment in the future.

Anaplastic Lymphoma Kinase (ALK)-Negative Anaplastic Large Cell Non-Hodgkin Lymphoma as a Rare Differential Diagnosis of Lung Cancer: A Case Report

Anaplastic large cell lymphomas (ALCL) are a group of sporadic malignancies that generally have an aggressive clinical course, especially the subtype of anaplastic lymphoma kinase (ALK)-negative ALCL. The appropriate diagnostic study modalities must be chosen to make an accurate diagnosis and promptly initiate specific treatment. We present the clinical case of a 72-year-old male patient with dyspnea on small efforts accompanied by diaphoresis and a weight loss of 10 kg in two months. Physical examination revealed adenopathy in the cervical region and bilateral pleural effusion. The pleural and lung biopsies revealed poorly differentiated metastatic adenocarcinomas. A multidisciplinary analysis was carried out; the typical clinical-radiographic presentation of adenocarcinoma was ruled out with immunohistochemistry, thus determining a diagnosis of ALK-negative anaplastic large cell non-Hodgkin's lymphoma. This case represented a diagnostic and therapeutic challenge since it is a rare entity with a poor prognosis, and there are only a few studies about the choice of appropriate chemotherapy in these patients.

Therapeutic Antibodies in Medicine

Antibody engineering has developed into a wide-reaching field, impacting a multitude of industries, most notably healthcare and diagnostics. The seminal work on developing the first monoclonal antibody four decades ago has witnessed exponential growth in the last 10-15 years, where regulators have approved monoclonal antibodies as therapeutics and for several diagnostic applications, including the remarkable attention it garnered during the pandemic. In recent years, antibodies have become the fastest-growing class of biological drugs approved for the treatment of a wide range of diseases, from cancer to autoimmune conditions. This review discusses the field of therapeutic antibodies as it stands today. It summarizes and outlines the clinical relevance and application of therapeutic antibodies in treating a landscape of diseases in different disciplines of medicine. It discusses the nomenclature, various approaches to antibody therapies, and the evolution of antibody therapeutics. It also discusses the risk profile and adverse immune reactions associated with the antibodies and sheds light on future applications and perspectives in antibody drug discovery.

Cutaneous Lymphoma and Antibody-Directed Therapies

The introduction of monoclonal antibodies such as rituximab to the treatment of cancer has greatly advanced the treatment scenario in onco-hematology. However, the response to these agents may be limited by insufficient efficacy or resistance. Antibody–drug conjugates are an attractive strategy to deliver payloads of toxicity or radiation with high selectivity toward malignant targets and limited unwanted effects. Primary cutaneous lymphomas are a heterogeneous group of disorders and a current area of unmet need in dermato-oncology due to the limited options available for advanced cases. This review briefly summarizes our current understanding of T and B cell lymphomagenesis, with a focus on recognized molecular alterations that may provide investigative therapeutic targets. The authors reviewed antibody-directed therapies investigated in the setting of lymphoma: this term includes a broad spectrum of approaches, from antibody–drug conjugates such as brentuximab vedotin, to bi-specific antibodies, antibody combinations, antibody-conjugated nanotherapeutics, radioimmunotherapy and, finally, photoimmunotherapy with specific antibody–photoadsorber conjugates, as an attractive strategy in development for the future management of cutaneous lymphoma.

Anti-CD30 antibody-drug conjugate therapy in lymphoma: current knowledge, remaining controversies, and future perspectives

CD30 is overexpressed in several lymphoma types, including classic Hodgkin lymphoma (cHL), some peripheral T-cell lymphomas (PTCL), and some cutaneous T-cell lymphomas. The antibody-drug conjugate brentuximab vedotin targets CD30-positive cells and has been evaluated for the treatment of various lymphoma entities. This narrative review summarizes 10 years of experience with brentuximab vedotin for the treatment of CD30-positive lymphomas, discusses novel therapies targeting CD30 in development, and highlights remaining controversies relating to CD30-targeted therapy across lymphoma types. The collective body of evidence for brentuximab vedotin demonstrates that exploitation of CD30 can provide sustained benefits across a range of different CD30-positive lymphomas, in both clinical trials and real-world settings. Preliminary experience with brentuximab vedotin in combination with immune checkpoint inhibitors for relapsed/refractory cHL is encouraging, but further exploration is required. The optimal use of brentuximab vedotin for first-line therapy of PTCL remains to be determined. Further research is required on brentuximab vedotin treatment in high-risk patient populations, and in rare lymphoma subtypes, for which no standard of care exists. Novel therapies targeting CD30 include chimeric antigen receptor therapies and bispecific antibody T-cell engagers, which may be expected to further improve outcomes for patients with CD30-positive lymphomas in the coming years.

Gene Expression Signatures for the Accurate Diagnosis of Peripheral T-Cell Lymphoma Entities in the Routine Clinical Practice

PURPOSE

Peripheral T-cell lymphoma (PTCL) includes heterogeneous clinicopathologic entities with numerous diagnostic and treatment challenges. We previously defined robust transcriptomic signatures that distinguish common PTCL entities and identified two novel biologic and prognostic PTCL-not otherwise specified subtypes (PTCL-TBX21 and PTCL-GATA3). We aimed to consolidate a gene expression-based subclassification using formalin-fixed, paraffin-embedded (FFPE) tissues to improve the accuracy and precision in PTCL diagnosis.

MATERIALS AND METHODS

We assembled a well-characterized PTCL training cohort (n = 105) with gene expression profiling data to derive a diagnostic signature using fresh-frozen tissue on the HG-U133plus2.0 platform (Affymetrix, Inc, Santa Clara, CA) subsequently validated using matched FFPE tissues in a digital gene expression profiling platform (nCounter, NanoString Technologies, Inc, Seattle, WA). Statistical filtering approaches were applied to refine the transcriptomic signatures and then validated in another PTCL cohort (n = 140) with rigorous pathology review and ancillary assays.

RESULTS

In the training cohort, the refined transcriptomic classifier in FFPE tissues showed high sensitivity (> 80%), specificity (> 95%), and accuracy (> 94%) for PTCL subclassification compared with the fresh-frozen-derived diagnostic model and showed high reproducibility between three independent laboratories. In the validation cohort, the transcriptional classifier matched the pathology diagnosis rendered by three expert hematopathologists in 85% (n = 119) of the cases, showed borderline association with the molecular signatures in 6% (n = 8), and disagreed in 8% (n = 11). The classifier improved the pathology diagnosis in two cases, validated by clinical findings. Of the 11 cases with disagreements, four had a molecular classification that may provide an improvement over pathology diagnosis on the basis of overall transcriptomic and morphological features. The molecular subclassification provided a comprehensive molecular characterization of PTCL subtypes, including viral etiologic factors and translocation partners.

CONCLUSION

We developed a novel transcriptomic approach for PTCL subclassification that facilitates translation into clinical practice with higher precision and uniformity than conventional pathology diagnosis.

Harnessing the Potential of Chimeric Antigen Receptor T-Cell Therapy for the Treatment of T-Cell Malignancies: A Dare or Double Dare?

Historical standard of care treatments of T-cell malignancies generally entailed the use of cytotoxic and depleting approaches. These strategies are, however, poorly validated and record dismal long-term outcomes. More recently, the introduction and approval of chimeric antigen receptor (CAR)-T cell therapy has revolutionized the therapy of B-cell malignancies. Translating this success to the T-cell compartment has so far proven hazardous, entangled by risks of fratricide, T-cell aplasia, and product contamination by malignant cells. Several strategies have been utilized to overcome these challenges. These include the targeting of a selective cognate antigen exclusive to T-cells or a subset of T-cells, disruption of target antigen expression on CAR-T constructs, use of safety switches, non-viral transduction, and the introduction of allogeneic compounds and gene editing technologies. We herein overview these historical challenges and revisit the opportunities provided as potential solutions. An in-depth understanding of the tumor microenvironment is required to optimally harness the potential of the immune system to treat T-cell malignancies.

Adverse Renal Effects of Anticancer Immunotherapy: A Review

Modern oncological therapy utilizes various types of immunotherapy. Immune checkpoint inhibitors (ICIs), chimeric antigen receptor T cells (CAR-T) therapy, cancer vaccines, tumor-targeting monoclonal antibodies (TT-mAbs), bispecific antibodies and cytokine therapy improve patients' outcomes. However, stimulation of the immune system, beneficial in terms of fighting against cancer, generates the risk of harm to other cells in a patient's body. Kidney damage belongs to the relatively rare adverse events (AEs). Best described, but still, superficially, are renal AEs in patients treated with ICIs. International guidelines issued by the European Society for Medical Oncology (ESMO) and the American Society of Clinical Oncology (ASCO) cover the management of immune-related adverse events (irAEs) during ICI therapy. There are fewer data concerning real occurrence and possible presentations of renal adverse drug reactions of other immunotherapeutic methods. This implies the need for the collection of safety data during ongoing clinical trials and in the real-life world to characterize the hazard related to the use of new immunotherapies and management of irAEs.

CD30+ Lymphoproliferative Disorders as Potential Candidates for CD30-Targeted Therapies

CONTEXT.—

In the early 1980s, a monoclonal antibody termed Ki-1 was developed against a cell line derived from a patient with Hodgkin lymphoma. This antibody detected a limited number of benign activated lymphocytes in lymphoid tissue, whereas in Hodgkin lymphoma it appeared to be nearly specific for Reed-Sternberg cells and their mononuclear variants. Subsequent studies showed that Ki-1 expression defined a new type of lymphoma that was later designated anaplastic large cell lymphoma with or without anaplastic large cell kinase expression/translocation. In the past 30 years, numerous new lymphoma entities have been defined, many of which are variably positive for CD30. Many virally transformed lymphoproliferative disorders are also frequently positive for CD30.

OBJECTIVE.—

To illustrate the broad spectrum of CD30+ hematologic malignancies and to provide an update of CD30-targeted therapies.

DATA SOURCES.—

Personal experiences and published works in PubMed.

CONCLUSIONS.—

Because of its low expression in normal tissue, CD30 was studied as a therapeutic target for many years. However, the first functional humanized antibody against CD30 was developed only about 10 years ago. Brentuximab vedotin is a humanized anti-CD30 antibody linked to a cytotoxin, and was approved by the US Food and Drug Administration in 2012 for treating refractory Hodgkin lymphoma and anaplastic large cell lymphoma. Since then, the list of Food and Drug Administration-approved CD30-targeted hematologic malignancies has grown. Recently, the therapies using tumor antigen-specific chimeric antigen receptor T cells targeting CD30 have incited a great deal of enthusiasm and are studied in clinical trials.

Antibody-Drug Conjugate Targets, Drugs and Linkers

Antibody-drug conjugates offer the possibility of directing powerful cytotoxic agents to a malignant tumor while sparing normal tissue. The challenge is to select an antibody target expressed exclusively or at highly elevated levels on the surface of tumor cells and either not all or at low levels on normal cells. The current review explores 78 targets that have been explored as antibody-drug conjugate targets. Some of these targets have been abandoned, 9 or more are the targets of FDA-approved drugs, and most remain active clinical interest. Antibody-drug conjugates require potent cytotoxic drug payloads, several of these small molecules are discussed, as are the linkers between the protein component and small molecule components of the conjugates. Finally, conclusions regarding the elements for the successful antibody-drug conjugate are discussed.

Stepping forward in antibody-drug conjugate development

Antibody-drug conjugates (ADCs) are cancer therapeutic agents comprised of an antibody, a linker and a small-molecule payload. ADCs use the specificity of the antibody to target the toxic payload to tumor cells. After intravenous administration, ADCs enter circulation, distribute to tumor tissues and bind to the tumor surface antigen. The antigen then undergoes endocytosis to internalize the ADC into tumor cells, where it is transported to lysosomes to release the payload. The released toxic payloads can induce apoptosis through DNA damage or microtubule inhibition and can kill surrounding cancer cells through the bystander effect. The first ADC drug was approved by the United States Food and Drug Administration (FDA) in 2000, but the following decade saw no new approved ADC drugs. From 2011 to 2018, four ADC drugs were approved, while in 2019 and 2020 five more ADCs entered the market. This demonstrates an increasing trend for the clinical development of ADCs. This review summarizes the recent clinical research, with a specific focus on how the in vivo processing of ADCs influences their design. We aim to provide comprehensive information about current ADCs to facilitate future development.

CAR-T cell therapy in T-cell malignancies: Is success a low-hanging fruit?

Chimeric antigen receptor T-cell (CAR-T) therapy has been prosperous in the treatment of patients with various types of relapsed/refractory (R/R) B-cell malignancies including diffuse large B-cell lymphoma (DLBCL), B-cell acute lymphoblastic leukemia (B-ALL), follicular lymphoma (FL), mantle cell lymphoma (MCL), and multiple myeloma (MM). However, this type of therapy has faced serious hindrances in combating T-cell neoplasms. R/R T-cell malignancies are generally associated with poor clinical outcomes, and the available effective treatment approaches are very limited. CAR-T therapy of T-cell malignancies has unique impediments in comparison with that of B-cell malignancies. Fratricide, T-cell aplasia, and product contamination with malignant T cells when producing autologous CAR-Ts are the most important challenges of CAR-T therapy in T-cell malignancies necessitating in-depth investigations. Herein, we highlight the preclinical and clinical efforts made for addressing these drawbacks and also review additional potent stratagems that could improve CAR-T therapy in T-cell malignancies.

CAR-T cell therapy in T-cell malignancies: Is success a low-hanging fruit?

Chimeric antigen receptor T-cell (CAR-T) therapy has been prosperous in the treatment of patients with various types of relapsed/refractory (R/R) B-cell malignancies including diffuse large B-cell lymphoma (DLBCL), B-cell acute lymphoblastic leukemia (B-ALL), follicular lymphoma (FL), mantle cell lymphoma (MCL), and multiple myeloma (MM). However, this type of therapy has faced serious hindrances in combating T-cell neoplasms. R/R T-cell malignancies are generally associated with poor clinical outcomes, and the available effective treatment approaches are very limited. CAR-T therapy of T-cell malignancies has unique impediments in comparison with that of B-cell malignancies. Fratricide, T-cell aplasia, and product contamination with malignant T cells when producing autologous CAR-Ts are the most important challenges of CAR-T therapy in T-cell malignancies necessitating in-depth investigations. Herein, we highlight the preclinical and clinical efforts made for addressing these drawbacks and also review additional potent stratagems that could improve CAR-T therapy in T-cell malignancies.

Enfortumab vedotin - next game-changer in urothelial cancer

Introduction: The therapeutic landscape of metastatic urothelial carcinoma (mUC) becomes increasingly dense: standard therapy remains cisplatin-based chemotherapy, followed by immunotherapy with checkpoint inhibitors as maintenance or second-line. New directions include erdafitinib, a fibroblast growth factor receptor (FGFR) inhibitor in patients with corresponding mutations in FGFR2/3 receptor. Enfortumab vedotin (EV) is an antibody-drug conjugate targeting nectin-4 and is conjugated with monomethyl auristatin E (MMAE). It received FDA approval based on phase I/II data recently and thus represents an alternative to established third-line chemotherapies with vinflunine, paclitaxel, or docetaxel.Areas covered: The aim of this review was to evaluate the added value of Enfortumab vedotin in the therapeutic landscape of mUC. Current therapeutic options and alternatives for the affected patients are described, followed by a detailed description of the characteristics and available results of EV. Ongoing studies are explained, the present significance of the substance is assessed and its further future potential is outlined.Expert opinion Enfortumab vedotin has shown encouraging efficacy and a good tolerability in phase I/II trials, especially in heavily pretreated patients and patients with liver metastases. It appears to outperform third-line chemotherapies; ongoing studies will show the future potential of EV in treatment sequence.

Convergent synthesis of hydrophilic monomethyl dolastatin 10 based drug linkers for antibody-drug conjugation

We report a modular approach to synthesize maleimido group containing hydrophilic dolastatin 10 (Dol10) derivatives as drug-linkers for the syntheses of antibody-drug conjugates (ADCs). Discrete polyethylene glycol (PEG) moieties of different chain lengths were introduced as part of the linker to impart hydrophilicity to these drug linkers. The synthesis process involved construction of PEG maleimido derivatives of the tetrapeptide intermediate (N-methylvaline-valine-dolaisoleucine-dolaproine), which were subsequently coupled with dolaphenine to generate the desired drug linkers. The synthetic method reported in this manuscript circumvents the use of highly cytotoxic Dol10 in its native form. By using trastuzumab (Herceptin®) as the antibody we have synthesized Dol10 containing ADCs. The presence of a discrete PEG chain in the drug linkers resulted in ADCs free from aggregation. The effect of PEG chain length on the biological activities of these Dol10 containing ADCs was investigated by in vitro cytotoxicity assays. ADCs containing PEG₆ and PEG₈ spacers exhibited the highest level of in vitro anti-proliferative activity against HER2-positive (SK-BR-3) human tumor cells. ADCs derived from Herceptin® and PEG₈-Dol10, at a dose of 10 mg kg^-1, effectively delayed the tumor growth and prolonged the survival time in mice bearing human ovarian SKOV-3 xenografts.