TROPHY-U-01: A Phase II Open-Label Study of Sacituzumab Govitecan in Patients With Metastatic Urothelial Carcinoma Progressing After Platinum-Based Chemotherapy and Checkpoint Inhibitors

Vaccine approaches to treat urothelial cancer

Bladder cancer (BC) accounts for about 4% of all malignancies. Non-muscle-invasive BC, 75% of cases, is treated with transurethral resection and adjuvant intravesical instillation, while muscle-invasive BC warrants cisplatin-based perioperative chemotherapy. Although immune-checkpoint inhibitors, antibody drug conjugates and targeted agents have provided dramatic advances, metastatic BC remains a generally incurable disease and clinical trials continue to vigorously evaluate novel molecules. Cancer vaccines aim at activating the patient's immune system against tumor cells. Several means of delivering neoantigens have been developed, including peptides, antigen-presenting cells, virus, or nucleic acids. Various improvements are constantly being explored, such as adjuvants use and combination strategies. Nucleic acids-based vaccines are increasingly gaining attention in recent years, with promising results in other malignancies. However, despite the recent advantages, numerous obstacles persist. This review is aimed at describing the different types of cancer vaccines, their evaluations in UC patients and the more recent innovations in this field.

Recent developments and future directions of first-line systemic therapy combined with immunotherapy for advanced or metastatic urothelial carcinoma: a historical perspective on treatment evolution

Urothelial carcinoma presents significant treatment challenges, especially in advanced stages. Traditionally managed with platinum-based chemotherapy, the advent of immunotherapies, particularly immune checkpoint inhibitors, has revolutionized urothelial carcinoma treatment. This review explores the evolution of urothelial carcinoma management, focusing on the transition from immune checkpoint inhibitors monotherapy to innovative combination therapies. Pembrolizumab, following the KEYNOTE-045 trial, emerged as a pivotal ICI in pretreated metastatic urothelial carcinoma, outperforming traditional chemotherapy. However, limitations surfaced in untreated metastatic urothelial carcinoma patients, particularly in those with low PD-L1 expression, as evidenced by trials like IMvigor130 and KEYNOTE-361. These challenges led to the exploration of combination therapies, including immune checkpoint inhibitors with platinum-based chemotherapy, tyrosine kinase inhibitors, and antibody-drug conjugates. Notably, the CheckMate 901 trial demonstrated improved outcomes with a nivolumab-chemotherapy combination. A significant breakthrough was achieved with the combination of enfortumab vedotin, an antibody-drug conjugates, and pembrolizumab, setting a new standard in first-line treatment for locally advanced or metastatic urothelial carcinoma. Future directions involve further exploration of antibody-drug conjugates and immune checkpoint inhibitors, as seen in the TROPHY-U-01 and TROPiCS-4 trials. The review concludes that the locally advanced or metastatic urothelial carcinoma treatment landscape is rapidly evolving, with combination therapies offering promising avenues for improved patient outcomes, signaling a new era in urothelial carcinoma management.

New Therapeutic Horizons for Advanced or Metastatic Penile Cancer

Penile cancer is a rare malignancy with a poor prognosis. Studies with single-agent immune checkpoint inhibitors (ICIs) have demonstrated efficacy, but response rates are low. Studies combining ICIs with both chemotherapy and targeted therapy are ongoing. Up to 50% of penile cancer cases are associated with human papillomavirus (HPV). HPV-targeting therapies, such as HPV-targeting vaccines and T-cell receptor therapies, are an area of active investigation. Penile cancer cells also express cell surface antigens that may be targeted by the emerging class of antibody-drug conjugates.

A Phase 2 Study of Sitravatinib in Combination with Nivolumab in Patients with Advanced or Metastatic Urothelial Carcinoma

BACKGROUND AND OBJECTIVE

Checkpoint inhibitor therapy (CPI) has demonstrated survival benefits in urothelial carcinoma (UC); however, not all patients benefit from CPI due to resistance. Combining sitravatinib, a multitargeted receptor tyrosine kinase inhibitor of TYRO3, AXL, and MERTK (TAM) receptors and VEGFR2, with CPI may improve antitumor responses. Our objective was to assess the efficacy and safety of sitravatinib plus nivolumab in patients with advanced/metastatic UC.

METHODS

The 516-003 trial (NCT03606174) is an open-label, multicohort phase 2 study evaluating sitravatinib plus nivolumab in patients with advanced/metastatic UC enrolled in eight cohorts depending on prior treatment with CPI, platinum-based chemotherapy (PBC), or antibody-drug conjugate (ADC). Overall, 244 patients were enrolled and treated with sitravatinib plus nivolumab (median follow-up 14.1-38.2 mo). Sitravatinib (free-base capsules 120 mg once daily [QD] or malate capsule 100 mg QD) plus nivolumab (240 mg every 2 wk/480 mg every 4 wk intravenously).

KEY FINDINGS AND LIMITATIONS

The primary endpoint was objective response rate (ORR; RECIST v1.1). The secondary endpoints included progression-free survival (PFS) and safety. The Predictive probability design and confidence interval methods were used. Among patients previously treated with PBC, ORR, and median PFS were 32.1% and 3.9 mo in CPI-naïve patients (n = 53), 14.9% and 3.9 mo in CPI-refractory patients (n = 67), and 5.4% and 3.7 mo in CPI- and ADC-refractory patients (n = 56), respectively. Across all cohorts, grade 3 treatment-related adverse events (TRAEs) occurred in 51.2% patients and grade 4 in 3.3%, with one treatment-related death (cardiac failure). Immune-related adverse events occurred in 50.4% patients. TRAEs led to sitravatinib/nivolumab discontinuation in 6.1% patients.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Sitravatinib plus nivolumab demonstrated a manageable safety profile but did not result in clinically meaningful ORRs in patients with advanced/metastatic UC in the eight cohorts studied.

PATIENT SUMMARY

In this study, the combination of two anticancer drugs, sitravatinib and nivolumab, resulted in manageable side effects but no meaningful responses in patients with bladder cancer.

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.

The upregulation of POLR3G correlates with increased malignancy of bladder urothelium

Bladder cancer remains a significant health challenge due to its high recurrence and progression rates. This study aims to evaluate the role of POLR3G in the development and progression of bladder cancer and the potential of POLR3G to serve as a novel therapeutic target. We constructed a bladder cancer model in Wistar rats by administering N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN), which successfully induced a transition from normal mucosa to hyperplasia and ultimately to urothelial carcinoma. We observed a progressive upregulation of POLR3G expression during the bladder cancer development and progression. To investigate the functional role of POLR3G, we performed functional experiments in bladder cancer cell lines. The results demonstrated that knocking down POLR3G significantly inhibited cell proliferation, migration, and invasion. We further conducted RNA sequencing on POLR3G-knockdown bladder cancer cells, and Metascape was employed to perform the functional enrichment analysis of the differentially expressed genes (DEGs). Enrichment analysis revealed the enrichment of DEGs in the RNA polymerase and apoptotic cleavage of cellular proteins pathways, as well as their involvement in the Wnt and MAPK signaling pathways. The downregulation of Wnt pathway-related proteins such as Wnt5a/b, DVL2, LRP-6, and phosphorylated LRP-6 upon POLR3G knockdown was further confirmed by Western blotting, indicating that POLR3G might influence bladder cancer behavior through the Wnt signaling pathway. Our findings suggest that POLR3G plays a crucial role in bladder cancer progression and could serve as a potential therapeutic target. Future studies should focus on the detailed mechanisms by which POLR3G regulates these signaling pathways and its potential as a biomarker for early detection and prognosis of bladder cancer.

Biomarkers associated with survival in patients with platinum-refractory urothelial carcinoma treated with paclitaxel

BACKGROUND

Taxane- based chemotherapy is widely used in patients with platinum- and immunotherapy refractory, metastatic urothelial carcinoma (mUC). Outcomes are poor and biomarkers associated with outcome are lacking. We aim to identify cancer hallmarks associated with survival in patients receiving paclitaxel.

METHODS

Whole-transcriptome profiles were generated for a subset of patients enrolled in a randomised phase II study investigating paclitaxel and pazopanib in platinum refractory mUC (PLUTO, EudraCT 2011-001841-34). Estimates of gene expression were calculated and input into the Almac proprietary analysis pipeline and signature scores were calculated using ClaraT V3.0.0. Ten key gene signatures were assessed: Immuno-Oncology, Epithelial to Mesenchymal Transition, Angiogenesis, Proliferation, Cell Death, Genome Instability, Energetics, Inflammation, Immortality and Evading Growth. Hazard ratios were calculated using Cox regression model and Kaplan-Meier methods were used to estimate progression free survival (PFS) and overall survival (OS).

RESULTS

38 and 45 patients treated with paclitaxel or pazopanib were included. Patients with high genome instability expression treated with paclitaxel had significantly improved survival with a HR of 0.29 (95% CI: 0.14-0.61, p=0.001) and HR 0.34 (95% CI: 0.17-0.69, p=0.003) for PFS and OS, respectively. Similarly, patients with high evading growth suppressor expression treated with paclitaxel had improved PFS and OS with a HR of 0.35 (95% CI: 0.19-0.77, p=0.007) and HR 0.46 (95% CI: 0.23-0.91, p=0.026), respectively. No other gene signatures had significant impact on outcome. In both paclitaxel and pazopanib cohorts, angiogenesis activation was associated with worse PFS and OS, and VEGF targeted therapy did not improve outcomes.

CONCLUSION

High Genome-instability and Evading-growth suppressor biologies are associated with improved survival in patients with platinum refractory mUC receiving paclitaxel. These may refine mUC risk stratification and guide treatment decision in the future.

NECTIN4 Amplification Is Frequent in Solid Tumors and Predicts Enfortumab Vedotin Response in Metastatic Urothelial Cancer

PURPOSE

The anti-NECTIN4 antibody-drug conjugate enfortumab vedotin (EV) is approved for patients with metastatic urothelial cancer (mUC). However, durable benefit is only achieved in a small, yet uncharacterized patient subset. NECTIN4 is located on chromosome 1q23.3, and 1q23.3 gains represent frequent copy number variations (CNVs) in urothelial cancer. Here, we aimed to evaluate NECTIN4 amplifications as a genomic biomarker to predict EV response in patients with mUC.

MATERIALS AND METHODS

We established a NECTIN4-specific fluorescence in situ hybridization (FISH) assay to assess the predictive value of NECTIN4 CNVs in a multicenter EV-treated mUC patient cohort (mUC-EV, n = 108). CNVs were correlated with membranous NECTIN4 protein expression, EV treatment responses, and outcomes. We also assessed the prognostic value of NECTIN4 CNVs measured in metastatic biopsies of non-EV-treated mUC (mUC-non-EV, n = 103). Furthermore, we queried The Cancer Genome Atlas (TCGA) data sets (10,712 patients across 32 cancer types) for NECTIN4 CNVs.

RESULTS

NECTIN4 amplifications are frequent genomic events in muscle-invasive bladder cancer (TCGA bladder cancer data set: approximately 17%) and mUC (approximately 26% in our mUC cohorts). In mUC-EV, NECTIN4 amplification represents a stable genomic alteration during metastatic progression and associates with enhanced membranous NECTIN4 protein expression. Ninety-six percent (27 of 28) of patients with NECTIN4 amplifications demonstrated objective responses to EV compared with 32% (24 of 74) in the nonamplified subgroup (P < .001). In multivariable Cox analysis adjusted for age, sex, and Bellmunt risk factors, NECTIN4 amplifications led to a 92% risk reduction for death (hazard ratio, 0.08 [95% CI, 0.02 to 0.34]; P < .001). In the mUC-non-EV, NECTIN4 amplifications were not associated with outcomes. TCGA Pan-Cancer analysis demonstrated that NECTIN4 amplifications occur frequently in other cancers, for example, in 5%-10% of breast and lung cancers.

CONCLUSION

NECTIN4 amplifications are genomic predictors of EV responses and long-term survival in patients with mUC.

Trastuzumab-deruxtecan in solid tumors with HER2 alterations: from early phase development to the first agnostic approval of an antibody-drug conjugate

INTRODUCTION

Antibody-drug conjugates (ADCs) represent a revolutionary approach in the systemic treatment for both solid and hematologic tumors. Constituted by an antibody, a cytotoxic payload, and a linker, ADCs aim to selectively deliver cytotoxic agents to tumors while sparing normal tissues. Various ADCs have been tested and approved for multiple solid tumors so far, but if there is one that had a major impact on clinical practice, this is Trastuzumab-deruxtecan (T-DXd). Notably, T-DXd was approved for HER2-positive and HER2-low metastatic breast cancer (MBC), HER2-positive gastric cancer (GC), HER2-mutant non-small cell lung cancer (NSCLC) and HER2 3+ solid tumors. Moreover, it received Breakthrough Therapy Designation for HER2-positive colorectal cancer (CRC).

AREAS COVERED

We review preclinical and clinical data of T-DXd, focusing on early-phase ongoing trials exploring combination therapies to enhance the activity of T-DXd in HER2-expressing solid tumors.

EXPERT OPINION

The clinical use of T-DXd still raises questions about selection of patients, treatment duration, prioritization over other approved ADCs, and management of resistance. Concerns regarding the toxicity of T-DXd remain, particularly with combinations involving potentially toxic drugs. Advancements in biomarker identification and combination therapies offer promising avenues to enhance efficacy and overcome resistance to T-DXd, ultimately improving outcomes for patients with cancer.

Single-cell analysis of treatment-resistant prostate cancer: Implications of cell state changes for cell surface antigen-targeted therapies

Targeting cell surface molecules using radioligand and antibody-based therapies has yielded considerable success across cancers. However, it remains unclear how the expression of putative lineage markers, particularly cell surface molecules, varies in the process of lineage plasticity, wherein tumor cells alter their identity and acquire new oncogenic properties. A notable example of lineage plasticity is the transformation of prostate adenocarcinoma (PRAD) to neuroendocrine prostate cancer (NEPC)-a growing resistance mechanism that results in the loss of responsiveness to androgen blockade and portends dismal patient survival. To understand how lineage markers vary across the evolution of lineage plasticity in prostate cancer, we applied single-cell analyses to 21 human prostate tumor biopsies and two genetically engineered mouse models, together with tissue microarray analysis on 131 tumor samples. Not only did we observe a higher degree of phenotypic heterogeneity in castrate-resistant PRAD and NEPC than previously anticipated but also found that the expression of molecules targeted therapeutically, namely PSMA, STEAP1, STEAP2, TROP2, CEACAM5, and DLL3, varied within a subset of gene-regulatory networks (GRNs). We also noted that NEPC and small cell lung cancer subtypes shared a set of GRNs, indicative of conserved biologic pathways that may be exploited therapeutically across tumor types. While this extreme level of transcriptional heterogeneity, particularly in cell surface marker expression, may mitigate the durability of clinical responses to current and future antigen-directed therapies, its delineation may yield signatures for patient selection in clinical trials, potentially across distinct cancer types.

PD-L1 and nectin-4 expression and genomic characterization of bladder cancer with divergent differentiation

BACKGROUND

Bladder cancer with divergent differentiation (BCDD) comprises a heterogenous group of tumors with a poor prognosis, and differential expression of nectin-4 and programmed death ligand-1 (PD-L1) has been reported in BCDD. Importantly, nectin-4 expression in bladder cancer is associated with response to enfortumab vedotin, and PD-L1 expression is associated with responses to immune checkpoint inhibitors (ICIs).

METHODS

The authors conducted a retrospective review identifying 117 patients with advanced or metastatic BCDD who were treated at Winship Cancer Institute from 2011 to 2021. They performed immunohistochemistry staining for nectin-4 and PD-L1 expression by histologic subtype as well as genomic analysis of these patients, including RNA sequencing, whole-exome sequencing, and fusion detection analysis as well as a subgroup genomic analysis of patients with BCDD who received ICIs.

RESULTS

The results indicated that nectin-4 expression was highest in the groups who had the squamous and plasmacytoid subtypes, whereas the group that had the sarcomatoid subtype (70.8%) had the highest proportion of PD-L1-positive patients. Genomic analysis yielded several key findings, including a 50% RB1 mutation rate in patients who had small cell BCDD, targetable PIK3CA mutations across multiple subtypes of BCDD, and significantly higher expression of TEC in responders to ICIs.

CONCLUSIONS

In this study, the authors identified clinically relevant data on nectin-4 and PD-L1 expression in patients with rare bladder tumors. They also identified several novel findings in the genomic analysis that highlight the role of precision medicine in this population of patients. Larger, prospective studies are needed to validate these hypothesis-generating data.

Ocular side effects of anticancer agents used in the treatment of gynecologic cancers

The treatment landscape of gynecologic cancers has expanded in recent years to include targeted and immune-based therapies. These therapies often have ocular side effects not seen with conventional chemotherapies, some of which can cause significant visual impairment if not recognized in a timely fashion. Clinicians must know how to appropriately identify, mitigate, and treat these ocular adverse events. Management often involves working with an interdisciplinary team of eye specialists, and it is important to know when to refer patients for specialized care. Proactive identification of eye specialists, especially in rural and community settings where access to care can be limited, may be necessary. Here, we discuss the management of common ocular toxicities seen with novel anticancer agents used to treat gynecologic cancers.

A single-arm, multicenter, phase 2 clinical study of recombinant humanized anti-HER2 monoclonal antibody-MMAE conjugate (MRG002) in HER2-positive unresectable locally advanced or metastatic urothelial carcinoma

BACKGROUND

MRG002 is a novel HER2-targeted antibody-drug conjugate being investigated in the MRG002-006 trial to evaluate the efficacy and safety in HER2-positive urothelial carcinoma patients.

METHODS

This is an open-label, single-arm, multicenter phase II study. Eligibility criteria included: histologically confirmed HER2 IHC 2 + or 3 + UC, prior received ≥ 1 standard treatment. Patients in this study received MRG002 every 3 weeks until progressive disease or unacceptable toxicity. The primary endpoint was confirmed ORR per RECIST 1.1.

RESULTS

As of February 24, 2023, a total of 43 patients were enrolled. The median age was 60. 9 patients were dosed at 2.6 mg/kg and 34 patients were dosed at 2.2 mg/kg. At baseline, most patients (29/43) received ≥ 2 lines of treatment and 35 (81.4%) patients had prior ICI therapy. FISH test was performed in 41 patients and 9 (22.0%) were positive. By the cut-off date, 41 patients were evaluable and the ORR was 53% (95%CI：38.9%-67.5%), with 6.9% CR, and the DCR was 83.7% (95%CI：70.0%-91.9%). The median PFS and OS for the 43 patients were 7.0 months (95%CI：5.4-NE) and 14.9 months (95%CI：11.9-NE), respectively. The ORR was 77.8% in 9 patients with positive HER2 FISH results. Most common treatment-related AEs were anemia (51.2%), alopecia (44.2%) and neutropenia (39.5%); most were grade 1 or 2.

CONCLUSION

Preliminary results of MRG002 demonstrated a clinically meaningful response in pretreated HER-2 positive unresectable locally advanced or metastatic UC patients. MRG002 at 2.2 mg/kg was well tolerated with a manageable toxicity.

Pathology focused review of morphologic subtypes and molecular variants of urothelial carcinoma with an emphasis on clinical/treatment relevance

Urothelial carcinoma (UC) has significant morbidity, mortality, and remains the most financially costly carcinoma to manage and treat. This review will cover special morphologic features of UC that may be noted by the pathologist and any subsequent significance in terms of clinical management or treatment considerations as mentioned or recommended in the latest WHO 2022 classification of GU tumors. Many important potentially therapy altering morphologic findings can be consistently identified and reported on routine microscopic examination of hematoxylin and eosin (H&E) stained slides. Furthermore, there has been a rapid advancement of molecular diagnostics and tailored therapies throughout oncology, and we will briefly highlight some of these as they relate to the management of UC. We will actively attempt to limit the discussion of histologic descriptions or pathologic diagnostic criteria of these entities and focus rather on the recognition of their importance/implication for clinicians who must make clinical management decisions based upon these findings. Finally, the importance of open lines of communication with the pathologists who review clinical specimens as well as their practice and reporting methods cannot be overstated.

A Podcast on Platinum Eligibility and Treatment Sequencing in Platinum-Eligible Patients with Locally Advanced or Metastatic Urothelial Carcinoma

The treatment landscape for patients with advanced urothelial carcinoma continues to evolve. Enfortumab vedotin plus pembrolizumab has received Food and Drug Administration approval based on recent phase 3 trial data showing superior efficacy compared with first-line platinum-based chemotherapy; however, its distinct toxicity profile may make it less suitable for some patients, and availability in some countries may be limited by cost considerations. Consequently, platinum-based chemotherapy is expected to remain an important first-line treatment option. Choice of platinum regimen (cisplatin- or carboplatin-based) is informed by assessment of clinical characteristics, including performance status, kidney function, and presence of peripheral neuropathy or heart failure. For patients without disease progression after completing platinum-based chemotherapy, avelumab first-line maintenance treatment is recommended by international guidelines. For patients who have disease progression, pembrolizumab is the preferred approach. Additionally, following results from a recent phase 3 trial, nivolumab plus cisplatin-based chemotherapy has also received Food and Drug Administration approval and is an additional first-line treatment option for cisplatin-eligible patients. Later-line options for patients with advanced urothelial carcinoma, depending on prior treatment, may include enfortumab vedotin, erdafitinib (for patients with FGFR2/3 mutations or fusions/rearrangements), sacituzumab govitecan, and platinum rechallenge. For the small proportion of patients ineligible for any platinum-based chemotherapy (i.e., unsuitable for cisplatin or carboplatin), immune checkpoint inhibitor monotherapy with pembrolizumab or atezolizumab is a first-line treatment option, although approved agents vary between countries. In summary, this podcast discusses recent developments in the treatment landscape for advanced urothelial carcinoma, eligibility for platinum-based chemotherapy, potential first-line treatment options, and treatment sequencing. Supplementary file1 (MP4 246907 KB).

Trophoblast Cell Surface Antigen 2 Expression in Thymic Carcinoma: Brief Report

Introduction

Trophoblast cell surface antigen 2 (TROP2) is a transmembrane glycoprotein overexpressed in various cancer types. Although TROP2-targeting therapy is currently attracting attention, little is known about TROP2 expression in thymic carcinoma.

Methods

TROP2 gene expression in thymic epithelial tumors was analyzed using RNA-sequencing (RNA-seq) data for 122 cases obtained from The Cancer Genome Atlas. Immunohistochemistry (IHC) staining with anti-TROP2 antibody (SP295) was performed in 26 cases of thymic carcinoma tissues surgically resected at Juntendo University.

Results

RNA-seq data analysis from The Cancer Genome Atlas revealed that TACSTD2 (gene encoding TROP2) expression was significantly higher in thymic carcinoma than in thymoma (adjusted p = 6.64e-05). There was also a trend of increasing expression in the order of thymoma type B1, B2, B3, and thymic carcinoma. As for IHC in thymic carcinoma, TROP2 expression was localized to the membrane of cancer cells. Intensity 0, 1, and 2 was observed in six (23.1%), 11 (42.3%), and nine (34.6%) cases, respectively, leading to TROP2 positivity in 20 cases (76.9%). The median proportion of TROP2-positive tumor cells and the median H-score were 25.0% (range: 0%-100%) and 25.0 (range: 0-200), respectively. No relevant factors were identified in the analysis of TROP2 expression and patient background. Although not significant, high TROP2 expression (H-score ≥ 50) tended to be associated with shorter survival.

Conclusions

TROP2 expression in thymic carcinoma was confirmed by both RNA-seq and IHC, with high expression observed in IHC for intensity (76.9%) and proportion. TROP2 could be a potential target in thymic carcinoma.

Antibody-Drug Conjugates as Novel Therapeutic Agents for Non-Small Cell Lung Carcinoma with or without Alterations in Oncogenic Drivers

Antibody-drug conjugates (ADCs) are an emerging class of therapeutics for lung cancer, and several are currently in development for this malignancy. The structure of these molecules is based on an antibody that targets a protein on the lung cancer cell surface and a cytotoxic payload attached by a linker. Many protein targets, including TROP2, c-MET, CEACAM5, HER2, and HER3 have been identified. In metastatic non-small cell lung carcinoma (NSCLC) without alterations in oncogenic drivers, platinum-based chemotherapy and immune checkpoint inhibitors (ICIs) targeting the programmed death-1/programmed death-ligand 1 (PD1/PDL1) interaction are the standard first-line treatments. In patients with EGFR-mutated or ALK-rearranged NSCLC, tyrosine kinase inhibitors (TKIs) are recommended. However, although the prognosis of patients with metastatic NSCLC differs between such with and without alterations in oncogenic drivers, most patients eventually experience disease progression. A novel therapeutic class is needed in routine practice to overcome the mechanisms of resistance to ICIs and EGFR/ALK TKIs. Several ADCs have already been approved for other cancers, such as breast cancer and urothelial carcinoma. This review summarizes the knowledge about the efficacy and tolerance profiles of ADCs targeting TROP2, HER2, HER3, CEACAM5 and c-MET in metastatic NSCLC with and without alterations in oncogenic drivers.

C-Reactive Protein-Albumin Ratio Predicts Objective Response to Enfortumab Vedotin in Metastatic Urothelial Carcinoma

BACKGROUND

Enfortumab vedotin (EV), an antibody-drug conjugate that targets Nectin-4, is used for patients with metastatic urothelial carcinoma who have experienced progression on platinum-based chemotherapy and checkpoint inhibitors. Despite the widespread use of the drug, evidence remains scarce regarding clinical indicators that can predict the response to EV treatment.

OBJECTIVE

We aimed to explore the predictive value of clinical indicators derived from peripheral blood tests for treatment responses to EV.

METHODS

We utilized records of 109 patients with metastatic urothelial carcinoma treated by EV from our multi-institutional dataset. Receiver operating characteristic curve analyses for predicting objective responses including several indicators from blood examinations, such as C-reactive protein-albumin ratio (CAR), hemoglobin, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and lactate dehydrogenase, were performed. The optimal cutoff points were determined by the Youden index. Logistic regression analyses for achieving objective responses to EV treatment were performed among these indicators.

RESULTS

The median age of the cohort was 74 years, and the median follow-up duration was 10 months for the entire group. Median overall survival and progression-free survival from the initiation of EV were 12 and 6 months, respectively. The objective response rate and disease control rate were 48% and 70%, respectively. The receiver operating characteristic curve analysis aimed at predicting the achievement of an objective response to EV showed that the concordant index for the CAR was 0.774, significantly surpassing other indicators such as hemoglobin level, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and serum lactate dehydrogenase. The Youden index identified an optimal cutoff value of 1 for CAR (mg/L for C-reactive protein and g/dL for serum albumin level) in predicting the objective response to EV treatment. Using the cutoff value for the CAR, the cohort was divided into 32 patients (29%) with lower CAR and 77 patients (71%) with higher CAR. The objective response rate was observed to be 84% in the lower CAR group and 32% in the higher CAR group (p < 0.0001). A logistic regression analysis revealed that an Eastern Cooperative Oncology Group Performance Status ≥1 (p = 0.04) and a CAR ≥1 (p < 0.001) were identified as independent predictors for the objective response to EV.

CONCLUSIONS

The evaluation of the CAR from a concise blood examination at the initiation of EV could effectively predict the treatment response to EV in patients with metastatic urothelial carcinoma after the progression of platinum-based chemotherapy and checkpoint inhibitors.

Antibody-Drug Conjugates in Urothelial Cancer: From Scientific Rationale to Clinical Development

Antibody-drug conjugates (ADCs) have been a significant advancement in cancer therapy, particularly for urothelial cancer (UC). These innovative treatments, originally developed for hematological malignancies, use target-specific monoclonal antibodies linked to potent cytotoxic agents. This rational drug design efficiently delivers cancer cell-killing agents to cells expressing specific surface proteins, which are abundant in UC owing to their high antigen expression. UC is an ideal candidate for ADC therapy, as it enhances on-target efficacy while mitigating systemic toxicity. In recent years, considerable progress has been made in understanding the biology and mechanisms of tumor progression in UC. However, despite the introduction of immune checkpoint inhibitors, advanced UC is characterized by rapid progression and poor survival rates. Targeted therapies that have been developed include the anti-nectin 4 ADC enfortumab vedotin and the fibroblast growth factor receptor inhibitor erdafitinib. Enfortumab vedotin has shown efficacy in prospective studies in patients with advanced UC, alone and in combination with pembrolizumab. The anti-Trop-2 ADC sacituzumab govitecan has also demonstrated effectiveness in single-armed studies. This review highlights the mechanism of action of ADCs, their application in mono- and combination therapies, primary mechanisms of resistance, and future perspectives for their clinical use in UC treatment. ADCs have proven to be an increasingly vital component of the therapeutic landscape for urothelial carcinoma, filling a gap in the treatment of this progressive disease.

Advancements in First-Line Treatment of Metastatic Bladder Cancer: EV-302 and Checkmate-901 Insights and Future Directions

Advanced bladder cancer patients have historically failed to achieve prolonged duration of response to conventional chemotherapy and needed better first-line treatment regimens. The approval of nivolumab in combination with gemcitabine and cisplatin and pembrolizumab with antibody-drug conjugate enfortumab vedotin has revolutionized the first-line treatment of advanced bladder cancer in many countries. In this review, we summarize the intricate differences between the two landmark clinical trials that led to their incorporation into the current standard of care for advanced bladder cancer. We further discuss newer novel treatment options in the second and subsequent lines of treatment on progression, like immunotherapy in combination with other agents, including fibroblast growth factors receptor inhibitors, human epidermal growth factor inhibitors, antibody-drug conjugates, tyrosine kinase inhibitors, and novel antibodies. Finally, we discuss the integration of these novel therapies into current clinical practice amidst the rapidly evolving landscape of advanced bladder cancer treatment, aiming to enhance patient outcomes.

Dark force rising: Reawakening and targeting of fetal-like stem cells in colorectal cancer

Stem cells play pivotal roles in maintaining intestinal homeostasis, orchestrating regeneration, and in key steps of colorectal cancer (CRC) initiation and progression. Intriguingly, adult stem cells are reduced during many of these processes. On the contrary, primitive fetal programs, commonly detected in development, emerge during tissue repair, CRC metastasis, and therapy resistance. Recent findings indicate a dynamic continuum between adult and fetal stem cell programs. We discuss critical mechanisms facilitating the plasticity between stem cell states and highlight the heterogeneity observed upon the appearance of fetal-like states. We focus on therapeutic opportunities that arise by targeting fetal-like CRC cells and how those concepts can be translated into the clinic.

The combination of immune checkpoint inhibitors and antibody-drug conjugates in the treatment of urogenital tumors: a review insights from phase 2 and 3 studies

With the high incidence of urogenital tumors worldwide, urinary system tumors are among the top 10 most common tumors in men, with prostate cancer ranking first and bladder cancer fourth. Patients with resistant urogenital tumors often have poor prognosis. In recent years, researchers have discovered numerous specific cancer antigens, which has led to the development of several new anti-cancer drugs. Using protein analysis techniques, researchers developed immune checkpoint inhibitors (ICIs) and antibody-conjugated drugs (ADCs) for the treatment of advanced urogenital tumors. However, tumor resistance often leads to the failure of monotherapy. Therefore, clinical trials of the combination of ICIs and ADCs have been carried out in numerous centers around the world. This article reviewed phase 2 and 3 clinical studies of ICIs, ADCs, and their combination in the treatment of urogenital tumors to highlight safe and effective methods for selecting individualized therapeutic strategies for patients. ICIs activate the immune system, whereas ADCs link monoclonal antibodies to toxins, which can achieve a synergistic effect when the two drugs are combined. This synergistic effect provides multiple advantages for the treatment of urogenital tumors.

Advancing neoadjuvant therapies in resectable non-small cell lung cancer: implications for novel treatment strategies and biomarker discovery

The delivery of neoadjuvant and perioperative therapies for non-small cell lung cancer has been radically altered by significant advances and by the incorporation of targeted therapies as well as immune checkpoint inhibitors alone or alongside conventional chemotherapy. This evolution has been particularly notable in the incorporation of immunotherapy and targeted therapy into the treatment of resectable NSCLC, where recent FDA approvals of drugs such as nivolumab and pembrolizumab, in combination with platinum doublet chemotherapy, have led to considerable improvements in pathological complete response rates and the potential for enhanced long-term survival outcomes. This review emphasizes the growing importance of biomarkers in optimizing treatment selection and explores the impact of emerging studies that challenge existing treatment paradigms and investigate novel therapeutic combinations poised to redefine standard of care practices. Furthermore, the discussion extends to the unmet needs within perioperative treatment assessment and prognostication, highlighting the prospective value of biomarkers in evaluating treatment responses and prognosis.

Stereotactic body radiation therapy is beneficial for a subgroup of patients with urothelial cancer and solitary metastatic disease: a single institution real-world experience

BACKGROUND

Standard treatment options for patients with metastatic urothelial cancer (mUC) include systemic platinum-based chemotherapy, immunotherapy, antibody-drug-conjugates, and targeted therapy. Oligometastatic disease (OMD) may be an intermediate state between localized and generalized cancer. The best treatment strategy for OMD and oligoprogressive (OPD) disease is poorly studied in mUC but local stereotactic body radiation therapy (SBRT) could be an option to avoid or delay systemic treatment. The aim of this study was to assess the efficacy and feasibility of SBRT given in a real-world patient population.

METHODS

All patients with mUC treated with SBRT at Karolinska University Hospital, Stockholm, Sweden between 2009 and 2022 were included in this study. Baseline clinical characteristics, treatment data, SBRT dosimetry data and treatment outcome were collected retrospectively. The study endpoints were local control rate (LCR), progression-free-survival (PFS), overall survival (OS) and feasibility of SBRT.

RESULTS

In total 39 patients were treated with SBRT. The median follow-up was 25.6 months. The LCR was 82%. PFS and OS were 4.1 and 26.2 months, respectively. Treatment was well tolerated; all patients but one (treatment related pain) completed the planned SBRT. Number of metastases irradiated with SBRT was significantly associated with outcome; patients with only one irradiated lesion had more favourable PFS compared to individuals with 2 or more metastases (HR 4.12, 95% CI: 1.81-9.38, p = 0.001). A subgroup of patients (15%) achieved a sustained long-term survival benefit and never required systemic treatments after SBRT.

CONCLUSIONS

SBRT was well tolerated and associated with high LCR. A subpopulation of patients with single metastatic lesion achieved long-term OS and never required subsequent systemic treatment after SBRT. Prospective randomized studies are warranted to discover treatment predictive biomarkers and to investigate the role of SBRT in oligometastatic UC.

Efficacy and safety of antibody-drug conjugates in the treatment of urothelial cell carcinoma: a systematic review and meta-analysis of prospective clinical trials

Introduction: Urothelial carcinoma (UC) is a refractory disease for which achieving satisfactory outcomes remains challenging with current surgical interventions. Antibody-drug conjugates (ADCs) are a novel class of targeted therapeutics that have demonstrated encouraging results for UC. Although there is a limited number of high-quality randomized control trials (RCTs) examining the use of ADCs in patients with UC, some prospective non-randomized studies of interventions (NRSIs) provide valuable insights and pertinent information. We aim to assess the efficacy and safety of ADCs in patients with UC, particularly those with locally advanced and metastatic diseases. Methods: A systematic search was conducted across PubMed, Embase, the Cochrane Library, and Web of Science databases to identify pertinent studies. Outcomes, such as the overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), adverse events (AEs), and treatment-related adverse events (TRAEs), were extracted for further analyses. Results: Twelve studies involving 1,311 patients were included in this meta-analysis. In terms of tumor responses, the pooled ORR and DCR were 40% and 74%, respectively. Regarding survival analysis, the pooled median PFS and OS were 5.66 months and 12.63 months, respectively. The pooled 6-month PFS and OS were 47% and 80%, while the pooled 1-year PFS and OS were 22% and 55%, respectively. The most common TRAEs of the ADCs were alopecia (all grades: 45%, grades ≥ III: 0%), decreased appetite (all grades: 34%, grades ≥ III: 3%), dysgeusia (all grades: 40%, grades ≥ III: 0%), fatigue (all grades: 39%, grades ≥ III: 5%), nausea (all grades: 45%, grades ≥ III: 2%), peripheral sensory neuropathy (all grades: 37%, grades ≥ III: 2%), and pruritus (all grades: 32%, grades ≥ III: 1%). Conclusion: The meta-analysis in this study demonstrates that ADCs have promising efficacies and safety for patients with advanced or metastatic UC. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42023460232.

Trop2-targeted therapies in solid tumors: advances and future directions

Trophoblast cell surface antigen 2 (Trop2) is overexpressed in a range of solid tumors and participants in multiple oncogenic signaling pathways, making it an attractive therapeutic target. In the past decade, the rapid development of various Trop2-targeted therapies, notably marked by the advent of the antibody-drug conjugate (ADC), revolutionized the outcome for patients facing Trop2-positive tumors with limited treatment opinions, such as triple-negative breast cancer (TNBC). This review provides a comprehensive summary of advances in Trop2-targeted therapies, including ADCs, antibodies, multispecific agents, immunotherapy, cancer vaccines, and small molecular inhibitors, along with in-depth discussions on their designs, mechanisms of action (MOAs), and limitations. Additionally, we emphasize the clinical research progress of these emerging Trop2-targeted agents, focusing on their clinical application and therapeutic efficacy against tumors. Furthermore, we propose directions for future research, such as enhancing our understanding of Trop2's structure and biology, exploring the best combination strategies, and tailoring precision treatment based on Trop2 testing methodologies.

Application of the ESMO Magnitude of Clinical Benefit Scale to assess the clinical benefit of antibody drug conjugates in solid cancer: a systematic descriptive analysis of phase III and pivotal phase II trials

OBJECTIVE

The aim of this study was to assess the clinical benefit value of approved antibody drug conjugates (ADCs) for solid tumours using the European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS) V.1.1.

DESIGN

Systematic descriptive analysis.

DATA SOURCES

PubMed was searched for publications from 1 January 2000 to 18 October 2023.

ELIGIBILITY CRITERIA

We included the phase III randomised controlled trials or phase II pivotal trials leading to approval of ADCs in solid tumours.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and discrepancies were resolved by consensus in the presence of a third investigator.

RESULTS

ESMO-MCBS Scores were calculated for 16 positive clinical trials of eight ADCs, which were first approved by the US Food and Drug Administration (FDA), the European Medicines Agency (EMA), the China National Medical Products Administration and the Japanese Pharmaceuticals and Medical Devices Agency for solid cancers. Among 16 trials, 4 (25%) met the ESMO-MCBS benefit threshold grade, while 12 (75%) of the regimens did not meet the ESMO-MCBS benefit threshold grade. 5 (31%) of the 16 trials had no published scorecard on the ESMO website due to the approval by other jurisdictions but not by the FDA or EMA. Discrepancies between our results and the ESMO scorecard were observed in 4 (36%) of 11 trials, mostly owing to integration of more recent data.

CONCLUSIONS

ESMO-MCBS is an important tool for assessing the clinical benefit of cancer drugs, but not all drugs met the meaningful benefit threshold.

RC48-Antibody-Drug Conjugate in Metastatic Urothelial Carcinoma: A Multicenter Real-World Study in China

OBJECTIVES

RC48 is an antibody-drug conjugate (ADC) that targets HER2. In China, RC48 is approved for patients with HER-2-positive metastatic urothelial carcinoma (mUC) who have failed at least platinum-based chemotherapy. This study aimed to evaluate RC48 for mUC in a cohort of real-world patients.

MATERIALS AND METHODS

We retrospectively collected data from 103 mUC patients from 12 centers between July 2021 and August 2023 in China. RC48 alone or with immunotherapy was administered until disease progression, intolerable toxicity, death, or other reasons. The objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and incidence of treatment-related adverse events (TRAEs) were evaluated.

RESULTS

The median age of the patients was 68 years, and 68.0% were men. Twenty-nine (28.2%) patients received RC48 alone; 73 (70.9%) received RC48 combination therapy. The response rates were as follows: complete response in 2 (1.9%) patients, partial response in 50 (48.5%) patients, stable disease in 30 (29.1%) patients. The ORR was 50.5%. In patients with ≥80 years, Eastern Cooperative Oncology Group (ECOG) performance status ≥2 and creatinine clearance rate (CCr) <30 mL/min, the ORR was 75%, 48.6%, and 40.0%, respectively. The median PFS was 6 (3.9-8.1) months, and the median OS was not reached. The most reported TRAEs were peripheral sensory neuropathy (53.4%), alopecia (42.7%), asthenia (38.8%), decreased appetite (35.9%) and weight loss (35.9%) and TRAE did not increase in patients with poor condition or impaired renal function.

CONCLUSION

Administration of RC48 for real-world patients is both effective and safe. mUC patients can benefit from RC48-based therapy, regardless of their poor condition or impaired renal function.

Preclinical evidence for the use of anti-Trop-2 antibody-drug conjugate Sacituzumab govitecan in cerebral metastasized castration-resistant prostate cancer

PURPOSE

Improved survival rates have been observed in castration-resistant prostate cancer (CRPC) due to advancements in treatment options. However, individuals with brain metastases still have limited therapeutic options and an unfavorable prognosis. Therefore, there is an urgent need to explore new therapeutic avenues, such as antibody-drug conjugates (ADCs), which have demonstrated significant clinical activity against active brain metastases in solid tumors. Our objective was to determine the expression levels of the ADC targets Trop-2 and NECTIN-4 in cerebral metastasized CRPC (mCRPC).

METHODS

Immunohistochemical staining of Trop-2 and NECTIN-4 with evaluation of H-score was performed in CRPC brain metastases (n = 31). Additionally, we examined Trop-2 protein expression in prostate cancer cell lines and studied their responsiveness to the anti-Trop-2 ADC Sacituzumab govitecan (SG) in vitro.

RESULTS

Our analysis revealed that most patients exhibited moderate to strong Trop-2 expression [n = 27/31 with H-score ≥100, median H-score 220 (IQR 180-280)], while NECTIN-4 was absent in all cerebral metastases. Mechanistically, we demonstrated that the efficacy of SG depends on Trop-2 expression levels in vitro. Overexpression of Trop-2 in Trop-2-negative PC-3 cells led to sensitization to SG, whereas CRISPR-Cas9-mediated knockdown of Trop-2 in Trop-2-expressing DU-145 cells conferred resistance to SG.

CONCLUSION

The substantial expression of Trop-2 in cerebral metastases, along with our preclinical in vitro results, supports the efficacy of SG in treating cerebral mCRPC. Thus, our results extend the understanding of the potential of ADCs in prostate cancer treatment and provide an additional treatment strategy for the challenging subset of patients with cerebral metastases.

Current Advances in the Management of Nonurothelial Subtypes of Bladder Cancer

Urothelial cancer (UC) is the most common histology seen in bladder tumors. The 2022 WHO classification of urinary tract tumors includes a list of less common subtypes (formerly known as variants) for invasive UC which are considered high-grade tumors. This review summarizes the most recent advances in the management of selected nonurothelial subtypes of bladder cancer: squamous cell carcinoma, small cell carcinoma, sarcomatoid urothelial carcinoma, micropapillary carcinoma, plasmacytoid carcinoma, adenocarcinoma, and urachal carcinoma. The role of neoadjuvant and adjuvant chemotherapy has not been well characterized for most of these histologies, and prospective data are extremely limited. Participation in clinical trials is recommended in advanced disease.

Advancements in Urothelial Cancer Care: Optimizing Treatment for Your Patient

The standard treatment paradigm for muscle invasive bladder cancer has been neoadjuvant cisplatin-based chemotherapy followed by radical cystectomy. However, efforts are ongoing to personalize treatment by incorporating biomarkers to better guide treatment selection. In addition, bladder preservation strategies are aimed at avoiding cystectomy in well-selected patients. Similarly, in the metastatic urothelial cancer space, the standard frontline treatment option of platinum-based chemotherapy has changed with the availability of data from EV-302 trial, making the combination of enfortumab vedotin (EV) and pembrolizumab the preferred first-line treatment option. Here, we examine the optimization of treatment intensity and sequencing, focusing on the challenges and opportunities associated with EV/pembrolizumab therapy, including managing toxicities and exploring alternative dosing approaches. Together, these articles provide a comprehensive overview of contemporary strategies in bladder cancer management, highlighting the importance of individualized treatment approaches, ongoing research, and multidisciplinary collaboration to improve patient outcomes in this complex disease landscape.

Side effects of drug-antibody conjugates enfortumab-vedotin and sacituzumab-govitecan in targeted therapy in cancer

OBJECTIVE

Antibody-drug conjugates (ADC), enfortumab-vedotin (EV) and sacituzumab-govitecan are new drugs in the treatment of urologic tumors, whose safety profile has not been fully investigated. Therefore, the aim of our study was to evaluate adverse events related to both agents reported to VigiBase, the World Health Organization's global pharmacovigilance database.

METHODS

We employed Bayesian disproportionality analysis based on the information component (IC) to explore the safety profile associated with both therapies. Additionally, we used the proportional reporting ratio approach to examine the safety profile further.

RESULTS

We identified 41,752 reports connected to ADC therapy (EV: n=5359; SG: n=36,393). In the EV subgroup, most reports were associated with dermatologic (38.6%), neurologic adverse events (16.5%), or adverse laboratory assessments (19.4%). In contrast, reports in the SG subgroup were mainly associated with gastrointestinal adverse events (24.2%) and adverse laboratory assessments (39.0%). Adverse laboratory assessments in both cohorts were often based on haematotoxic adverse events.

CONCLUSION

We could provide a comprehensive real-world safety profile of EV and SG using a global pharmacovigilance database. Based on the safety signals explored in this study, further research regarding the impact of these side effects on patient outcomes is justified.

Assessing safety concerns of interstitial lung disease associated with antibody-drug conjugates: a real-world pharmacovigilance evaluation of the FDA adverse event reporting system

BACKGROUND

Antibody-drug conjugates have revolutionized cancer therapy due to their selectivity and efficacy. However, concerns have been raised regarding the potential effects of trastuzumab deruxtecan in interstitial lung diseases.

AIM

This study aimed to investigate the safety signals and time to onset of antibody-drug conjugates induced interstitial lung disease.

METHOD

We utilized the FDA Adverse Event Reporting System database (2004-2022) to identify interstitial lung disease safety signals in 13 FDA-approved antibody-drug conjugates. Disproportionality analysis was conducted to estimate the reporting odds ratios for interstitial lung disease.

RESULTS

Seven antibody-drug conjugates exhibited safety signals of interstitial lung disease: trastuzumab deruxtecan [reporting odds ratio, ROR (95% confidence intervals, CI) = 64.15 (57.07-72.10)], enfortumab vedotin [ROR (95% CI) = 5.24 (3.25-8.43)], trastuzumab emtansine [ROR (95% CI) = 3.62 (2.90-4.53)], brentuximab vedotin [ROR (95% CI) = 3.22 (2.49-4.17)], polatuzumab vedotin [ROR (95% CI) = 2.56 (1.59-4.12)], gemtuzumab ozogamicin [ROR (95% CI) = 2.53 (1.70-3.78)], and inotuzumab ozogamicin [ROR (95% CI) = 2.33 (1.21-4.49)]. Five antibody-drug conjugates with limited reports were excluded from further analysis: belantamab mafodotin, loncastuximab tesirine, mirvetuximab sorafenib, tisotumab vedotin, and moxetumomab pasudotox. Japan and the United States were the primary reporting countries.

CONCLUSION

This real-world study highlights high safety signals of interstitial lung disease associated with antibody-drug conjugates. Clinicians should be aware of these safety concerns and risk factors and implement early identification measures for their patients. Future research should prioritize comprehensively exploring the relationship between antibody-drug conjugates and lung diseases.

Antibody Drug Conjugates in Urological Cancers: A Review of the Current Landscape

PURPOSE OF REVIEW

Our review delves into the progress across urological malignancies and discusses ongoing challenges and future directions in antibody-drug conjugate (ADC) development, emphasising their transformative potential in cancer care.

RECENT FINDINGS

ADCs have advanced from hematologic to solid tumours, notably in breast cancer, and are now pivotal in metastatic urological cancers as both monotherapies and in combination regimens, underscored by the FDA's approval of enfortumab vedotin and sacituzumab govitecan for metastatic urothelial cancer. Progress in metastatic prostate cancer, particularly with ADCs targeting PSMA and STEAP1, is noteworthy, although renal cell cancer presents ongoing challenges. There is a continual search for agents in the metastatic, relapsed testicular cancer landscape. ADCs have emerged as a pivotal innovation in oncology, blending targeted antibody therapy with potent cytotoxic drugs, significantly advancing treatment options for urological malignancies.

Therapeutic Targets in Advanced Penile Cancer: From Bench to Bedside

Discovery of effective systemic therapies for patients with advanced penile cancer has been slow to occur. Comprehensive genomic profiling from several studies shed light on the molecular oncogenesis of penile squamous cell carcinoma (PSCC) and differences between HPV-related and unrelated tumors. While these two subsets of PSCC appear distinct in their biology, there are not yet specific treatment strategies recommended on that basis. Cell surface proteins have been identified that may potentially serve as drug targets for monoclonal antibodies or small molecule inhibitors. Here, we review some of the new biological insights regarding PSCC that could lead to improved therapies, as well as the related clinical trials recently completed or in progress. We conclude that antibody-drug conjugates are especially promising, as are the combinations of immune checkpoint inhibitors with other types of drugs.

Assessment of TROP2, CEACAM5 and DLL3 in metastatic prostate cancer: Expression landscape and molecular correlates

Therapeutic approaches targeting proteins on the surface of cancer cells have emerged as an important strategy for precision oncology. To capitalize on the potential impact of drugs targeting surface proteins, detailed knowledge about the expression patterns of the target proteins in tumor tissues is required. In castration-resistant prostate cancer (CRPC), agents targeting prostate-specific membrane antigen (PSMA) have demonstrated clinical activity. However, PSMA expression is lost in a significant number of CRPC tumors. The identification of additional cell surface targets is necessary to develop new therapeutic approaches. Here, we performed a comprehensive analysis of the expression heterogeneity and co-expression patterns of trophoblast cell-surface antigen 2 (TROP2), delta-like ligand 3 (DLL3), and carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) in CRPC samples from a rapid autopsy cohort. We show that DLL3 and CEACAM5 exhibit the highest expression in neuroendocrine prostate cancer (NEPC), while TROP2 is expressed across different CRPC molecular subtypes, except for NEPC. We further demonstrated that AR alterations were associated with higher expression of PSMA and TROP2. Conversely, PSMA and TROP2 expression was lower in RB1-altered tumors. In addition to genomic alterations, we show a tight correlation between epigenetic states, particularly histone H3 lysine 27 methylation (H3K27me3) at the transcriptional start site and gene body of TACSTD2 (encoding TROP2), DLL3, and CEACAM5, and their respective protein expression in CRPC patient-derived xenografts. Collectively, these findings provide insights into patterns and determinants of expression of TROP2, DLL3, and CEACAM5 with implications for the clinical development of cell surface targeting agents in CRPC.

Progress and Innovative Combination Therapies in Trop-2-Targeted ADCs

Precise targeting has become the main direction of anti-cancer drug development. Trophoblast cell surface antigen 2 (Trop-2) is highly expressed in different solid tumors but rarely in normal tissues, rendering it an attractive target. Trop-2-targeted antibody-drug conjugates (ADCs) have displayed promising efficacy in treating diverse solid tumors, especially breast cancer and urothelial carcinoma. However, their clinical application is still limited by insufficient efficacy, excessive toxicity, and the lack of biological markers related to effectiveness. This review summarizes the clinical trials and combination therapy strategies for Trop-2-targeted ADCs, discusses the current challenges, and provides new insights for future advancements.

The evolving treatment landscape of metastatic urothelial cancer

Cisplatin-based chemotherapy is currently the first-line standard of care for patients with metastatic urothelial cancer (mUC); however, up to 50% of patients are ineligible for cisplatin, necessitating alternative treatment options. Immune checkpoint inhibitors have been shown to be effective in cisplatin-ineligible patients. However, despite advances in the first-line setting, the prognosis remains poor, and challenges persist in selecting optimal therapies, treatment sequences and combination regimens. Maintenance therapy with avelumab revealed improved overall (OS) and progression-free survival (PFS) compared with best supportive care alone in patients with platinum-responsive mUC. Antibody-drug conjugates and targeted therapy with fibroblast growth factor receptor (FGFR) inhibitors have shown promise in selected patients, particularly in patients with metastatic disease that has progressed despite platinum-based chemotherapy. At the European Society of Medical Oncology Congress in 2023, groundbreaking results were presented from two phase III trials, EV-302/KEYNOTE-A39 and CheckMate 901, focusing on previously untreated mUC. In the former, the combination of enfortumab vedotin and pembrolizumab showed significant improvements in OS, PFS and overall response rate compared with chemotherapy alone; the combination of nivolumab with gemcitabine-cisplatin chemotherapy demonstrated a significant extension in median OS, PFS and overall response rate compared with chemotherapy alone. In addition, erdafitinib therapy resulted in significantly longer OS than chemotherapy among patients with mUC and FGFR alterations after previous treatment with immune checkpoint inhibitors. This comprehensive summary of the current treatment landscape for mUC incorporates clinical trial evidence and discussion of agents that are currently under investigation to provide support for clinical decision making and understanding of future therapeutic approaches.

Frequency and Nature of Genomic Alterations in ERBB2-Altered Urothelial Bladder Cancer

BACKGROUND

Human epidermal growth factor-2 (HER2) overexpression is an oncogenic driver in many solid tumors, including urothelial bladder cancer (UBC). In addition, activating mutations in the ERBB2 gene have been shown to play an oncogenic role similar to ERBB2 amplification.

OBJECTIVE

To describe and compare the frequency and nature of genomic alterations (GA) of ERBB2-altered (mutations, amplification) and ERBB2 wild-type UBC.

PATIENTS AND METHODS

Using a hybrid capture-based comprehensive profiling assay, 9518 UBC cases were grouped by ERBB2 alteration and evaluated for all classes of genomic alterations (GA), tumor mutational burden (TMB), microsatellite instability (MSI), genome-wide loss of heterozygosity (gLOH), and genomic mutational signature. PD-L1 expression was measured by immunohistochemistry (Dako 22C3). Categorical statistical comparisons were performed using Fisher's exact tests.

RESULTS

A total of 602 (6.3%) UBC cases featured ERBB2 extracellular domain short variant (SV) GA (ECDmut+), 253 (2.7%) cases featured ERBB2 kinase domain SV GA (KDmut+), 866 (9.1%) cases had ERBB2 amplification (amp+), and 7797 (81.9%) cases were ERBB2 wild-type (wt). European genetic ancestry of ECDmut+ was higher than ERBB2wt. Numerous significant associations were observed when comparing GA by group. Notably among these, CDKN2A/MTAP loss were more frequent in ERBB2wt versus ECDmut+ and amp+. ERBB3 GA were more frequent in ECDmut+ and KDmut+ than ERBB2wt. TERT GA were more frequent in ECDmut+, KDmut+, and amp+ versus ERBB2wt. TOP2A amplification was significantly more common in ECDmut+ and amp+ versus ERBB2wt, and TP53 SV GA were significantly higher in ERBB2 amp+ versus ERBB2wt. Mean TMB levels were significantly higher in ECDmut+, KDmut+, and amp+ than in ERBB2wt. Apolipoprotein B mRNA-editing enzyme, catalytic polypeptides (APOBEC) signature was more frequent in ECDmut+, KDmut+, and amp+ versus ERBB2wt. No significant differences were observed in PD-L1 status between groups, while gLOH-high status was more common in amp+ versus ERBB2wt. MSI-high status was more frequent in KDmut+ versus ERBB2wt, and in ERBB2wt than in amp+.

CONCLUSIONS

We noted important differences in co-occurring GA in ERBB2-altered (ECDmut+, KDmut+, amp+) versus ERBB2wt UBC, as well as higher mean TMB and higher APOBEC mutational signature in the ERBB2-altered groups. Our results can help refine future clinical trial designs and elucidate possible response and resistance mechanisms for ERBB2-altered UBC.

The potential roles of antibody-drug conjugates in head and neck squamous cell carcinoma

PURPOSE OF REVIEW

To summarize the actual antibody-drug conjugates (ADCs) tested for patients with advanced head and neck squamous cell carcinoma (HNSCC), outlining the results of safety and efficacy through published clinical trials.

RECENT FINDINGS

ADCs combine the specificity of mAbs with the cytotoxic drug (known as payload) via a chemical linker and it is designed to selectively deliver the ultratoxic payload directly to the target cancer cells. To date, various ADCs have been investigated in multiple solid malignancies and others are in clinical development. In this study, we provide an overview of the structure and biology of ADC and we review recent clinical experience with the ADC in patients with advanced HNSCC, followed by a brief discussion of the evolvement of ADC conception, drug resistance and future perspectives.

SUMMARY

ADC strategy is emerging as a potential active treatment in previously treated patients with advanced HNSCC. However, the recent improvement in the bioengineering of ADC and a better comprehension of sequencing and association strategies could provide more benefit to HNSCC patients in need of innovative therapy.

Durable Response to Enfortumab Vedotin Compared to Re-challenging Chemotherapy in Metastatic Urothelial Carcinoma After Checkpoint Inhibitors

BACKGROUND

Enfortumab vedotin (EV), an antibody-drug conjugate targeting Nectin-4, has been used for patients with metastatic urothelial carcinoma (mUC) after progressing on checkpoint inhibitors (CPIs). Re-challenging chemotherapy with platinum agents and continuing CPIs beyond progressive disease (PD) have often been chosen following PD on CPIs, and several studies indicate favorable treatment effects of re-challenging chemotherapy. There is little evidence for comparing EV and re-challenging chemotherapy in real-world clinical practice.

OBJECTIVE

The aim was to reveal the real-world treatment outcomes of EV, re-challenging chemotherapy, and continuing CPIs beyond PD in mUC patients.

PATIENTS AND METHODS

A multi-institutional dataset of 350 mUC patients treated with CPIs was utilized. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and duration of response (DOR) were evaluated to compare the treatment arms.

RESULTS

One hundred and nine mUC patients were treated with EV with a median follow-up of 6.4 months. The ORR and disease control rate (DCR) were 48% and 70%, respectively. The OS from PD on pembrolizumab exhibited significant differences among the three groups, with a median OS of 8, 14, and 29 months in continuing pembrolizumab beyond PD, re-challenging chemotherapy, and EV, respectively. When comparing the survival outcomes from the initiation of the treatment, there is neither a difference in OS (p = 0.124), PFS (p = 0.936), nor ORR (p = 0.816) between EV and re-challenging chemotherapy. Notably, the DOR in patients who achieved an objective response was significantly longer in the EV group than the re-challenging chemotherapy group (a median of 11 and 5 months, p = 0.049). For OS, the difference was not statistically significant (27 and 11 months in EV and re-challenging chemotherapy, respectively: p = 0.05).

CONCLUSIONS

A superior effect of EV on patient survival compared to re-challenging chemotherapy and continuing pembrolizumab beyond PD was observed in our real-world analysis, which is attributed to the durable DOR in EV treatment despite the similar ORR to re-challenging chemotherapy.

Updates on Urinary Bladder Tumors With Neuroendocrine Features

The most common neuroendocrine tumor in the urinary bladder is small cell carcinoma, which can be pure or mixed with components of urothelial or other histologic subtypes. Large cell neuroendocrine carcinoma of the bladder is rare and remains ill-defined but is increasingly recognized. Well-differentiated neuroendocrine tumor and paraganglioma can arise in the bladder but are very rare in this location. Recent advances in molecular characterization allowed for better classification and may offer improved stratification of these tumors.

Treatment Patterns and Attrition With Lines of Therapy for Advanced Urothelial Carcinoma in the US

Importance

The treatment paradigm for advanced urothelial carcinoma (aUC) has undergone substantial transformation due to the introduction of effective, novel therapeutic agents. However, outcomes remain poor, and little is known about current treatment approaches and attrition rates for patients with aUC.

Objectives

To delineate evolving treatment patterns and attrition rates in patients with aUC using a US-based patient-level sample.

Design, Setting, and Participants

This retrospective cohort study used patient-level data from the nationwide deidentified electronic health record database Flatiron Health, originating from approximately 280 oncology clinics across the US. Patients included in the analysis received treatment for metastatic or local aUC at a participating site from January 1, 2011, to January 31, 2023. Patients receiving treatment for 2 or more different types of cancer or participating in clinical trials were excluded from the analysis.

Main Outcomes and Measures

Frequencies and percentages were used to summarize the (1) treatment received in each line (cisplatin-based regimens, carboplatin-based regimens, programmed cell death 1 and/or programmed cell death ligand 1 [PD-1/PD-L1] inhibitors, single-agent nonplatinum chemotherapy, enfortumab vedotin, erdafitinib, sacituzumab govitecan, or others) and (2) attrition of patients with each line of therapy, defined as the percentage of patients not progressing to the next line.

Results

Of the 12 157 patients within the dataset, 7260 met the eligibility criteria and were included in the analysis (5364 [73.9%] men; median age at the start of first-line treatment, 73 [IQR, 66-80] years). All patients commenced first-line treatment; of these, only 2714 (37.4%) progressed to receive second-line treatment, and 857 (11.8%) advanced to third-line treatment. The primary regimens used as first-line treatment contained carboplatin (2241 [30.9%]), followed by PD-1/PD-L1 inhibitors (2174 [29.9%]). The PD-1/PD-L1 inhibitors emerged as the predominant choice in the second- and third-line (1412 of 2714 [52.0%] and 258 of 857 [30.1%], respectively) treatments. From 2019 onward, novel therapeutic agents were increasingly used in second- and third-line treatments, including enfortumab vedotin (219 of 2714 [8.1%] and 159 of 857 [18.6%], respectively), erdafitinib (39 of 2714 [1.4%] and 28 of 857 [3.3%], respectively), and sacituzumab govitecan (14 of 2714 [0.5%] and 34 of 857 [4.0%], respectively).

Conclusions and Relevance

The findings of this cohort study suggest that approximately two-thirds of patients with aUC did not receive second-line treatment. Most first-line treatments do not include cisplatin-based regimens and instead incorporate carboplatin- or PD-1/PD-L1 inhibitor-based therapies. These data warrant the provision of more effective and tolerable first-line treatments for patients with aUC.

The Safety and Efficacy of the Combination of Sacituzumab Govitecan and Palliative Radiotherapy-A Retrospective Multi-Center Cohort Study

Sacituzumab govitecan (SG) is a new treatment option for patients with metastatic triple-negative and hormone receptor-positive, HER2-negative breast cancer. This antibody-drug conjugate is currently approved as monotherapy. Palliative radiotherapy is frequently used to treat symptomatic metastases locally. Concurrent use of SG and irradiation was excluded in clinical trials of SG, and there are currently limited published data. We report here a systematic review, as well as a retrospective multi-center study of 17 patients with triple-negative breast cancer who received concurrent SG and radiotherapy. In these patients, concurrent use was found to be efficient, safe and well tolerated. There were no apparent differences in moderate or severe acute toxicity according to the timing of SG administration.

Sacituzumab Govitecan in Combination With Pembrolizumab for Patients With Metastatic Urothelial Cancer That Progressed After Platinum-Based Chemotherapy: TROPHY-U-01 Cohort 3

PURPOSE

Pembrolizumab is standard therapy for patients with metastatic urothelial cancer (mUC) who progress after first-line platinum-based chemotherapy; however, only approximately 21% of patients respond. Sacituzumab govitecan (SG) is a trophoblast cell surface antigen-2-directed antibody-drug conjugate with US Food and Drug Administration-accelerated approval to treat patients with locally advanced or mUC who previously received platinum-based chemotherapy and a checkpoint inhibitor (CPI). Here, we report the primary analysis of TROPHY-U-01 cohort 3.

METHODS

TROPHY-U-01 (ClinicalTrials.gov identifier: NCT03547973) is a multicohort, open-label phase II study. Patients were CPI-naïve and had mUC progression after platinum-based chemotherapy in the metastatic setting or ≤12 months in the (neo)adjuvant setting. Patients received 10 mg/kg of SG once on days 1 and 8 and 200 mg of pembrolizumab once on day 1 of 21-day cycles. The primary end point was objective response rate (ORR) per central review. Secondary end points included clinical benefit rate (CBR), duration of response (DOR) and progression-free survival (PFS) per central review, and safety.

RESULTS

Cohort 3 included 41 patients (median age 67 years; 83% male; 78% visceral metastases [29% liver]). With a median follow-up of 14.8 months, the ORR was 41% (95% CI, 26.3 to 57.9; 20% complete response rate), CBR was 46% (95% CI, 30.7 to 62.6), median DOR was 11.1 months (95% CI, 4.8 to not estimable [NE]), and median PFS was 5.3 months (95% CI, 3.4 to 10.2). The median overall survival was 12.7 months (range, 10.7-NE). Grade ≥3 treatment-related adverse events occurred in 61% of patients; most common were neutropenia (37%), leukopenia (20%), and diarrhea (20%).

CONCLUSION

SG plus pembrolizumab demonstrated a high response rate with an overall manageable toxicity profile in patients with mUC who progressed after platinum-based chemotherapy. No new safety signals were detected. These data support further evaluation of SG plus CPI in mUC.

Efficacy and Safety of Disitamab Vedotin in Patients With Human Epidermal Growth Factor Receptor 2-Positive Locally Advanced or Metastatic Urothelial Carcinoma: A Combined Analysis of Two Phase II Clinical Trials

PURPOSE

To evaluate the efficacy and safety of disitamab vedotin (DV, RC48-ADC), a novel humanized anti-human epidermal growth factor receptor 2 (HER2) antibody conjugated with monomethyl auristatin E, in patients with HER2-positive locally advanced or metastatic urothelial carcinoma (UC) refractory to standard or regular therapies.

PATIENTS AND METHODS

The data analyzed and reported are from two phase II, open-label, multicenter, single-arm studies (RC48-C005 and RC48-C009) in patients with HER2-positive (immunohistochemistry 3+ or 2+) locally advanced or metastatic UC who have progressed on at least one previous line of systemic chemotherapy. Patients received DV treatment (2 mg/kg IV infusion, once every 2 weeks). The primary end point was objective response rate (ORR) assessed by a blinded independent review committee (BIRC). Progression-free survival (PFS), overall survival (OS), and safety were also assessed.

RESULTS

One hundred and seven patients were enrolled in total. The overall confirmed ORR by BIRC was 50.5% (95% CI, 40.6 to 60.3). Consistent results were observed in prespecified subgroups including patients with liver metastasis and patients previously treated with anti-PD-1/L1 therapies. By the cutoff date of May 10, 2022, the median duration of response was 7.3 months (95% CI, 5.7 to 10.8). The median PFS and OS were 5.9 months (95% CI, 4.3 to 7.2) and 14.2 months (95% CI, 9.7 to 18.8), respectively. The most common treatment-related adverse events (TRAEs) were peripheral sensory neuropathy (68.2%), leukopenia (50.5%), AST increased (42.1%), and neutropenia (42.1%). Fifty-eight (54.2%) patients experienced grade ≥3 TRAEs, including peripheral sensory neuropathy (18.7%) and neutropenia (12.1%).

CONCLUSION

DV demonstrated a promising efficacy with a manageable safety profile in patients with HER2-positive locally advanced or metastatic UC who had progressed on at least one line of systemic chemotherapy.

Antibody-Drug Conjugates in the Treatment of Genitourinary Cancers: An Updated Review of Data

The treatment landscape of genitourinary cancers has significantly evolved over the past few years. Renal cell carcinoma, bladder cancer, and prostate cancer are the most common genitourinary malignancies. Recent advancements have produced new targeted therapies, particularly antibody-drug conjugates (ADCs), due to a better understanding of the underlying oncogenic factors and molecular mechanisms involved. ADCs function as a 'drug delivery into the tumor' system. They are composed of an antigen-directed antibody linked to a cytotoxic drug that releases cytotoxic components after binding to the tumor cell's surface antigen. ADCs have been proven to be extremely promising in the treatment of several cancer types. For GU cancers, this novel treatment has only benefited patients with metastatic urothelial cancer (mUC). The rest of the GU cancer paradigm does not have any FDA-approved ADC treatment options available yet. In this study, we have thoroughly completed a narrative review of the current literature and summarized preclinical studies and clinical trials that evaluated the utility, activity, and toxicity of ADCs in GU cancers, the prospects of ADC development, and the ongoing clinical trials. Prospective clinical trials, retrospective studies, case reports, and scoping reviews were included.

Lysine Methyltransferase 9 (KMT9) Is an Actionable Target in Muscle-Invasive Bladder Cancer

Novel treatment modalities are imperative for the challenging management of muscle-invasive and metastatic BC to improve patient survival rates. The recently identified KMT9, an obligate heterodimer composed of KMT9α and KMT9β, regulates the growth of various types of tumors such as prostate, lung, and colon cancer. While the overexpression of KMT9α was previously observed to be associated with aggressive basal-like MIBC in an analysis of patients' tissue samples, a potential functional role of KMT9 in this type of cancer has not been investigated to date. In this study, we show that KMT9 regulates proliferation, migration, and invasion of various MIBC cell lines with different genetic mutations. KMT9α depletion results in the differential expression of genes regulating the cell cycle, cell adhesion, and migration. Differentially expressed genes include oncogenes such as EGFR and AKT1 as well as mediators of cell adhesion or migration such as DAG1 and ITGA6. Reduced cell proliferation upon KMT9α depletion is also observed in Pten/Trp53 knockout bladder tumor organoids, which cannot be rescued with an enzymatically inactive KMT9α mutant. In accordance with the idea that the catalytic activity of KMT9 is required for the control of cellular processes in MIBC, a recently developed small-molecule inhibitor of KMT9 (KMI169) also impairs cancer cell proliferation. Since KMT9α depletion also restricts the growth of xenografts in mice, our data suggest that KMT9 is an actionable novel therapeutic target for the treatment of MIBC.

Single Cell Analysis of Treatment-Resistant Prostate Cancer: Implications of Cell State Changes for Cell Surface Antigen Targeted Therapies

Targeting cell surface molecules using radioligand and antibody-based therapies has yielded considerable success across cancers. However, it remains unclear how the expression of putative lineage markers, particularly cell surface molecules, varies in the process of lineage plasticity, wherein tumor cells alter their identity and acquire new oncogenic properties. A notable example of lineage plasticity is the transformation of prostate adenocarcinoma (PRAD) to neuroendocrine prostate cancer (NEPC)--a growing resistance mechanism that results in the loss of responsiveness to androgen blockade and portends dismal patient survival. To understand how lineage markers vary across the evolution of lineage plasticity in prostate cancer, we applied single cell analyses to 21 human prostate tumor biopsies and two genetically engineered mouse models, together with tissue microarray analysis (TMA) on 131 tumor samples. Not only did we observe a higher degree of phenotypic heterogeneity in castrate-resistant PRAD and NEPC than previously anticipated, but also found that the expression of molecules targeted therapeutically, namely PSMA, STEAP1, STEAP2, TROP2, CEACAM5, and DLL3, varied within a subset of gene-regulatory networks (GRNs). We also noted that NEPC and small cell lung cancer (SCLC) subtypes shared a set of GRNs, indicative of conserved biologic pathways that may be exploited therapeutically across tumor types. While this extreme level of transcriptional heterogeneity, particularly in cell surface marker expression, may mitigate the durability of clinical responses to novel antigen-directed therapies, its delineation may yield signatures for patient selection in clinical trials, potentially across distinct cancer types.

Advances in tumor microenvironment and underlying molecular mechanisms of bladder cancer: a systematic review

Bladder cancer is one of the most frequent malignant tumors of the urinary system. The prevalence of bladder cancer among men and women is roughly 5:2, and both its incidence and death have been rising steadily over the past few years. At the moment, metastasis and recurrence of advanced bladder cancer-which are believed to be connected to the malfunction of multigene and multilevel cell signaling network-remain the leading causes of bladder cancer-related death. The therapeutic treatment of bladder cancer will be greatly aided by the elucidation of these mechanisms. New concepts for the treatment of bladder cancer have been made possible by the advancement of research technologies and a number of new treatment options, including immunotherapy and targeted therapy. In this paper, we will extensively review the development of the tumor microenvironment and the possible molecular mechanisms of bladder cancer.