Real-world use, dose intensity, and adherence to enfortumab vedotin in locally advanced or metastatic urothelial cancer

BACKGROUND

Enfortumab vedotin (EV) monotherapy is approved for the treatment of advanced urothelial cancer as later-line therapy (post-immunotherapy and -platinum-chemotherapy) and as earlier-line therapy (cisplatin-ineligible, at least 1 prior therapy). We examined real-world EV monotherapy use, dose intensity and adherence across 280 US cancer clinics.

METHODS

This postmarketing study used data from a nationwide (United States) deidentified patient-level electronic health record-derived database. Included were patients with advanced urothelial cancer initiating EV on or after December 19, 2019 (date of accelerated approval). We summarized characteristics of EV users using descriptive statistics and computed metrics of EV use, EV dose intensity, and EV treatment adherence.

RESULTS

We identified 416 advanced urothelial cancer patients initiating EV monotherapy. More than half of patients (55.3%) received EV as later-line therapy (3L+), and nearly half (44.7%) received EV as earlier line therapy (1 or 2L). Dosing frequency (mean [SD] 2.4 [0.5] treatments per 28 day cycle) and dose (1.1 [0.2] mg/kg) were lower than label indication guidelines (1.25 mg/kg, Day 1, 8, 15 of a 28 day cycle). Only 58.8% of patients received an average of >2 treatments per 28-day cycle.

CONCLUSIONS

Among patients with advanced urothelial cancer treated with EV monotherapy in contemporary practice, EV dosing frequency, and dosage was lower in clinical practice than recommended in the product labeling. Further research is required to understand clinical factors and outcomes associated with the differences observed.

Peripheral neuropathy and nerve electrophysiological changes with enfortumab vedotin in patients with advanced urothelial carcinoma: a prospective multicenter cohort study

BACKGROUND

Enfortumab vedotin is a novel antibody-drug conjugate used as a third-line therapy for the treatment of urothelial cancer. We aimed to elucidate the effect of enfortumab vedotin-related peripheral neuropathy on its efficacy and whether enfortumab vedotin-induced early electrophysiological changes could be associated with peripheral neuropathy onset.

METHODS

Our prospective multicenter cohort study enrolled 34 patients with prior platinum-containing chemotherapy and programmed cell death protein 1/ligand 1 inhibitor-resistant advanced urothelial carcinoma and received enfortumab vedotin. The best overall response, progression-free survival, overall survival, and safety were assessed. Nerve conduction studies were also performed in 11 patients.

RESULTS

The confirmed overall response rate and disease control rate were 52.9% and 73.5%, respectively. The median overall progression-free survival and overall survival were 6.9 and 13.5 months, respectively, during a median follow-up of 8.6 months. The patients with disease control had significantly longer treatment continuation and overall survival than did those with uncontrolled disease. Peripheral neuropathy occurred in 12.5% of the patients. The overall response and disease control rates were 83.3% and 100%, respectively: higher than those in patients without peripheral neuropathy (p = 0.028 and p = 0.029, respectively). Nerve conduction studies indicated that enfortumab vedotin reduced nerve conduction velocity more markedly in sensory nerves than in motor nerves and the lower limbs than in the upper limbs, with the sural nerve being the most affected in the patients who developed peripheral neuropathy (p = 0.011).

CONCLUSION

Our results indicated the importance of focusing on enfortumab vedotin-induced neuropathy of the sural nerve to maximize efficacy and improve safety.

Biomarkers of Response to Anti-NECTIN4 Antibody-Drug Conjugate Enfortumab Vedotin in Urothelial Cancer

Initial studies indicated that NECTIN4 expression is widespread in metastatic urothelial cancer (mUC), which led to approval of the anti-NECTIN4 antibody-drug conjugate (ADC) enfortumab vedotin (EV) for unselected patients with mUC. However, the recent literature suggests that there has been overestimation of membranous NECTIN4 expression in UC, which is a prerequisite for EV binding. It is well established from the development of Her2-targeting ADCs that treatment response is strongly dependent on membranous expression level of the relevant target antigen. In this context, it has been demonstrated that membranous NECTIN4 expression correlates with EV responses and outcomes. Another promising biomarker could be NECTIN4 copy number alteration, a genomic alteration that occurs in approximately 25% of mUC cases, which is associated with strong membranous NECTIN4 expression. Patients with NECTIN4 amplification exhibit an objective response rate of >90% to EV monotherapy and long-term survival. Given the heterogeneous expression of NECTIN4 in UC, future biomarker research is essential for the development of biomarker-driven mUC treatment strategies to further improve outcomes for patients with mUC. PATIENT SUMMARY: We reviewed current evidence on biomarkers for predicting response to enfortumab vedotin (EV) treatment for metastatic urinary tract cancer (mUC). Studies to date have shown that patients with high levels of the protein NECTIN4 on their cancer cells respond well to EV. This information has the potential to guide future treatment strategies for mUC.

Comparison of the efficacy of enfortumab vedotin between patients with metastatic urothelial carcinoma who were treated with avelumab or pembrolizumab: real-world data from a multi-institutional study in Japan

OBJECTIVES

Enfortumab vedotin (EV) is a novel antibody-drug conjugate approved for metastatic urothelial carcinoma (UC) refractory to prior treatment with immune checkpoint inhibitors (ICIs). However, the difference in efficacy of EV after each ICIs and prognostic factors are not well known. We aimed to compare the efficacy of EV in patients with metastatic UC who were treated with avelumab or pembrolizumab and to identify the prognostic factors.

METHODS

The records of 100 patients with advanced metastatic UC who received EV after the administration of either avelumab or pembrolizumab were retrospectively collected from five academic hospitals in Japan.

RESULTS

The median follow-up period was 6.7 months. The median overall survival (OS) and progression-free survival (PFS) in the EV after avelumab/pembrolizumab group were not reached/14.7 months (p = 0.17) and 10.4/5.2 months (p = 0.039), respectively. The objective response rates (ORR) were 66.6% and 46.8% in EV after avelumab and EV after pembrolizumab groups, respectively (p = 0.14). Multivariate analysis identified histological variants, liver metastasis, low serum albumin levels, and high serum CRP level as significant poor prognostic factors. The median OS and PFS of cachexia patients with both low serum albumin levels and high serum CRP levels were 6.0 months and 0.93 months, respectively.

CONCLUSION

PFS was superior in patients treated with EV after avelumab to EV after pembrolizumab. However, OS showed no significant difference between the two groups. Because the prognosis of patients with cachexia is extremely poor, the initiation of EV should be discussed in these patients.

Enfortumab-vedotin use for urothelial carcinoma in two patients on hemodialysis

Enfortumab vedotin (EV) is a novel treatment option for patients with advanced/metastatic urothelial carcinoma who have progressed after chemotherapy and immunotherapy. Two patients at two different New England tertiary cancer care centers were treated with EV while concurrently receiving hemodialysis (HD), where a complete response to EV in both patients was noted. The use of EV in patients requiring HD is extrapolated from the available pharmacokinetic and pharmacodynamic literature on monoclonal antibodies in patients requiring HD. There is a paucity of data for the use of antibody-drug conjugates like EV in patients needing dialysis.

Quality of Life with Monoclonal Antibody Therapies for Locally Advanced or Metastatic Urothelial Carcinoma: A Systematic Review

CONTEXT

Monoclonal antibody (mAb) therapies have improved the prognosis for locally advanced or metastatic urothelial cancers (la/mUC) but little is known about health-related quality of life (HRQoL) with this mode of treatment.

OBJECTIVE

To conduct a systematic review of changes in HRQoL global health and domain scores in patients with la/mUC receiving mAb therapies.

EVIDENCE ACQUISITION

MEDLINE and the American Society of Clinical Oncology and European Society for Medical Oncology meeting databases were searched from January 2015 to June 18, 2022 in accordance with the Preferred Reported Items for Systematic Reviews and Meta-Analyses guidelines. Data were updated on February 3, 2023. Eligible studies were prospective trials assessing HRQoL in patients with la/mUC treated with mAbs. Patients treated for local disease or with radiotherapy or chemotherapy alone were excluded. Meta-analyses, reviews, and case reports were excluded. The validity of randomized trials was assessed using the Risk-of-Bias-2 (RoB2) tool and the strength of outcome evidence was rated using the Grading of Recommendations Assessment, Development and Evaluation approach. The data were analyzed via qualitative synthesis of the evidence.

EVIDENCE SYNTHESIS

Of the 1066 studies identified, nine were included (2364 patients); eight were interventional trials and one was an observational study. The mean change in global health score ranged from -2.8 to 1.9. Constipation, fatigue and pain symptoms, and emotional, physical, role and social functioning improved with treatment in at least two studies. No study demonstrated a significant improvement in global health score. Eight studies reported stability. In the RANGE trial, the global health score decreased. Only two studies had high internal validity according to RoB2 assessment. The HRQoL domain certainty was low, with moderate certainty only for the pain symptom domain. Disease- and treatment-related symptoms, tumor shrinkage, and disease recurrence were correlated to HRQoL.

CONCLUSIONS

Patient HRQoL with mAb therapies for la/mUC did not worsen over time. HRQoL is influenced by several factors related to treatment, tumor characteristics, and the patient's health condition. Evidence was moderate at best and further studies are needed.

PATIENT SUMMARY

We reviewed the evidence on health-related quality-of-life for patients with advanced bladder cancer treated with antibody therapies. We found that quality of life does not worsen on treatment, and sometimes improves. We conclude that these treatments do not negatively affect quality of life, but further studies are needed to draw solid conclusions.

Nectin-4 is frequently expressed in primary salivary gland cancer and corresponding lymph node metastases and represents an important treatment-related biomarker

Many locally advanced and metastatic salivary gland carcinomas (SGC) lack therapeutic targets. Enfortumab vedotin, an antibody-drug conjugate binding to Nectin-4, recently gained FDA approval for third-line urothelial carcinoma. Therefore, the aim of this study was to assess the expression of Nectin-4 in primary SGC and corresponding lymph node metastases and to correlate it with clinicopathological data. Immunohistochemical staining for Nectin-4 was performed for patients who had undergone surgery with curative intent for primary SGC of the parotid or submandibular gland in a tertiary referral center between 1990 and 2019. One hundred twenty-two primary SGC and twenty corresponding lymph node metastases were included. Nectin-4 was expressed in 80.3% of primary SGC with a mean Histo(H-)score of 61.2 and in 90.0% of lymph node metastases with a mean H-score of 75.6. A moderate or high Nectin-4 expression was found in 25.9% of salivary duct carcinomas (SaDu) and in 30.7% of adenoid cystic carcinomas (ACC). SaDu patients with a lower T-stage (p = 0.04), no loco-regional lymph node metastases (p = 0.049), no vascular invasion (p = 0.04), and no perineural spread (p = 0.03) showed a significantly higher mean Nectin-4 H-score. There was a statistical tendency towards a more favorable disease-free survival among SaDu patients with a higher Nectin-4 expression (p = 0.09). Nectin-4 is expressed in SGC and therefore represents a potential therapeutic target, especially in entities with a high rate of local recurrence and metastatic spread such as SaDu and ACC.

Antibody-drug conjugates for urothelial carcinoma

The standard of care for advanced urothelial carcinoma includes platinum chemotherapy and immunotherapy. Antibody-drug conjugates (ADCs), originally developed for hematologic malignancies, involve potent cytotoxic agents linked to antibodies that recognize tumor-specific antigens; this rational drug design allows for more on-target efficacy, while mitigating systemic toxicity. Herein, we review the emerging landscape of ADCs in urothelial carcinoma. The anti-Nectin-4 ADC enfortumab vedotin has demonstrated efficacy in prospective studies in patients with advanced urothelial carcinoma in several settings either alone or in combination with pembrolizumab. The anti-Trop-2 ADC sacituzumab govitecan has also shown efficacy in single-armed studies. Both conjugates have full or accelerated approval from the Food and Drug Administration. Common adverse events include rash and neuropathy for enfortumab vedotin and myelosuppression and diarrhea for sacituzumab govitecan. Several anti-human epidermal growth factor receptor 2 ADCs are in clinical trials, and in localized bladder cancer, the anti-epithelial cell adhesion molecule ADC oportuzumab monatox is being studied in patients refractory to intravesical bacillus calmette-guerin therapy. Antibody-drug conjugates for urothelial carcinoma are approved and emerging as therapies for patients with advanced urothelial carcinoma, filling a prior void for treatment of progressive disease. Ongoing studies are also evaluating these agents in the neoadjuvant and adjuvant settings.

Drug extravasation with Enfortumab vedotin

INTRODUCTION

Enfortumab vedotin is an antibody drug conjugate approved for management of pretreated locally advanced or metastatic urothelial carcinoma, which is associated with a rare risk of drug extravasation and soft tissue reactions.

CASE REPORT

We report two cases of EV extravasation with subsequent development of bullae and cellulitis.

MANAGEMENT AND OUTCOME

They were both treated for cellulitis and had conservative management without surgical intervention and were able to resume treatment with Enfortumab vedotin without subsequent adverse events.

DISCUSSION

We propose that EV acts as a vesicant upon extravasation, highlight measures to prevent extravasation events, and encourage appropriate measures when dealing such as attempt of aspiration, removal of catheter, application of compresses, and thorough documentation with photographic evidence.

Efficacy and Tolerability of Enfortumab Vedotin for Metastatic Urothelial Carcinoma: Early Experience in the Real World

BACKGROUND/AIM

This study retrospectively investigated the impact of enfortumab vedotin (EV) monotherapy on the oncological outcome, safety profile, and health-related quality of life (HRQoL) in patients with metastatic urothelial carcinoma.

PATIENTS AND METHODS

We assessed 26 consecutive patients who had received EV monotherapy after failure of platinum-based chemotherapy and immune checkpoint blockade therapy at our single institution from December 2021 to January 2023. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), incidence of adverse events (AEs), and EORTC QLQ-C30 as an HRQoL instrument were evaluated.

RESULTS

The ORR and DCR were 57.7% and 80.8%, respectively. EV was effective regardless of the patient and tumor characteristics, including the efficacy of previous systemic therapy, performance status, number of Bellmunt risk factors, and presence of variant histology. With a median follow-up time of 7.5 months, the median durations of PFS and OS were 5.4 months and 10.3 months, respectively. Grade ≥3 AEs included neutropenia (15.4%), fatigue (7.7%), appetite loss (7.7%), rash (3.8%), febrile neutropenia (3.8%), hyperglycemia (3.8%), and interstitial pneumonia (3.8%). AEs resulting in withdrawal of EV, interruption of EV, and dose reduction occurred in two (7.7%), nine (34.6%), and 13 patients (50.0%), respectively. The EORTC QLQ-C30 scores from baseline to post-EV introduction remained stable.

CONCLUSION

EV monotherapy demonstrated promising anti-tumor activity and tolerability in patients with metastatic urothelial carcinoma.

Physiologically based pharmacokinetic model to predict drug-drug interactions with the antibody-drug conjugate enfortumab vedotin

Enfortumab vedotin is an antibody-drug conjugate (ADC) comprised of a Nectin-4-directed antibody and monomethyl auristatin E (MMAE), which is primarily eliminated through P-glycoprotein (P-gp)-mediated excretion and cytochrome P450 3A4 (CYP3A4)-mediated metabolism. A physiologically based pharmacokinetic (PBPK) model was developed to predict effects of combined P-gp with CYP3A4 inhibitor/inducer (ketoconazole/rifampin) on MMAE exposure when coadministered with enfortumab vedotin and study enfortumab vedotin with CYP3A4 (midazolam) and P-gp (digoxin) substrate exposure. A PBPK model was built for enfortumab vedotin and unconjugated MMAE using the PBPK simulator ADC module. A similar model was developed with brentuximab vedotin, an ADC with the same valine-citrulline-MMAE linker as enfortumab vedotin, for MMAE drug-drug interaction (DDI) verification using clinical data. The DDI simulation predicted a less-than-2-fold increase in MMAE exposure with enfortumab vedotin plus ketoconazole (MMAE geometric mean ratio [GMR] for maximum concentration [Cmax], 1.15; GMR for area under the time-concentration curve from time 0 to last quantifiable concentration [AUClast], 1.38). Decreased MMAE exposure above 50% but below 80% was observed with enfortumab vedotin plus rifampin (MMAE GMR Cmax, 0.72; GMR AUClast, 0.47). No effect of enfortumab vedotin on midazolam or digoxin systemic exposure was predicted. Results suggest that combination enfortumab vedotin, P-gp, and a CYP3A4 inhibitor may result in increased MMAE exposure and patients should be monitored for potential adverse effects. Combination P-gp and a CYP3A4 inducer may result in decreased MMAE exposure. No exposure change is expected for CYP3A4 or P-gp substrates when combined with enfortumab vedotin.ClinicalTrials.gov identifier Not applicable.

Novel ADCs and combination therapy in urothelial carcinoma: latest updates from the 2023 ASCO-GU Cancers Symposium

Antibody-drug conjugates (ADCs) combine the cytotoxicity of small-molecule drugs with antibody targeting. Due to their precise and powerful effect, they have become a new hotspot and an important trend in the research and development of anti-tumor antibody drugs. Every year, exciting new developments and innovations in the treatment of urological tumors are introduced at the American Society of Clinical Oncology-Genitourinary (ASCO-GU) Cancers Symposium. In this article, we summarize some of the most impressive advances in new clinical trials and clinical data on ADCs in the 2023 ASCO-GU Cancers Symposium for the treatment of urothelial carcinoma.

Enfortumab Vedotin in Metastatic Urothelial Carcinoma: Survival and Safety in a European Multicenter Real-world Patient Cohort

Background

Treatment options for patients with urothelial cancer (UC) refractory to platinum and immunotherapy are limited and survival is short. Enfortumab vedotin (EV) is a monoclonal anti-NECTIN4 antibody conjugated to monomethyl auristatin. It was recently approved because of superior survival in comparison to standard-of-care (SOC) chemotherapy. Real-world patients, however, often have worse characteristics than patients included in clinical trials.

Objective

To analyze the efficacy and safety of EV in a cohort of real-world patients.

Design setting and participants

Retrospective data were collected from 23 hospitals and private practices for patients with metastatic and previously treated UC who received EV either when reimbursed by their insurance company before European Medicines Agency (EMA) approval, within a compassionate use program, or as SOC treatment after EMA approval. Imaging and therapy management were in accordance with local standards.

Outcome measurements and statistical analysis

Adverse events (AEs) were reported according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 criteria. Objective responses were evaluated according to Response Evaluation Criteria in Solid Tumors version 1.1. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.

Results and limitations

The median age for the 125 eligible patients was 66 yr (range 31-89). The Eastern Cooperative Oncology Group performance status (ECOG PS) was 0-1 for 76.0%, 2-4 for 13.6%, and unknown for 10.4% of patients. EV was administered in the fourth or later line for 44.8% of patients. The overall response rate was 41.6% (partial response 39.2%, complete response 2.4%). Median OS was 10.0 months (mo) (95% confidence interval 7.20-12.80) and median PFS was 5.0 mo (95% confidence interval 4.34-5.67). For patients with ECOG PS of 0-1, median OS was 14 mo. Any-grade AEs were observed in 67.2% and CTCAE grade ≥3 AEs in 30.4%. The most common AEs were peripheral sensory neuropathy and skin toxicity. Three fatal events (pneumonia, pneumonitis) occurred. Limitations include the retrospective design and short follow-up.

Conclusions

Administration of EV for real-world patients was feasible with an acceptable toxicity profile. No new safety signals were reported. Antitumor activity in our cohort was comparable to data previously reported for trials. In summary, our results support the use of EV in patients with metastatic UC.

Patient summary

Enfortumab vedotin is a medication that improved the survival of patients with bladder cancer in comparison to standard chemotherapy in clinical trials. However, patients included in clinical trials are highly selected and results for toxicities and improvements in survival do not always transfer to the real-world setting. We analyzed data for 125 patients who were treated with enfortumab vedotin. Our results are comparable to the outcomes from clinical trials regarding the safety and efficacy of this treatment.

[Antibody-drug conjugates as new therapeutic agents in uro-oncology]

Antibody-drug conjugates represent a new class of therapeutic agents that are already being used in the field of uro-oncology. They consist of an antibody directed against a specific tumour antigen linked to a cytotoxic substance ("payload") which acts after internalisation into the tumour cell and its release. Currently, approval in the European Union is restricted to enfortumab vedotin which is directed against nectin‑4 and carries the microtubule-inhibiting active ingredient monomethyl auristatin E (MMAE). Enfortumab vedotin is approved for locally advanced or metastatic urothelial carcinoma in the third line of therapy after platinum-based chemotherapy and after therapy with a programmed cell death (ligand) 1 (PD-[L]1) immune checkpoint inhibitor. However, an expansion of the indication of enfortumab vedotin as monotherapy and in combination with PD-(L)1 immune checkpoint inhibitors, as well as approval of other antibody-drug conjugates is expected in the future. This could sustainably change the therapy sequence in urothelial carcinoma. Currently, several clinical trials are recruiting in different therapeutic settings. This article presents the new substance class of antibody-drug conjugates, their mechanism of action, their representatives and clinical studies, and points out practice-relevant side effects and how to deal with them.

Enfortumab Vedotin-related Cutaneous Toxicity and Radiographic Response in Patients with Urothelial Cancer: A Single-center Experience and Review of the Literature

Enfortumab vedotin (EV) is an antibody-drug conjugate approved for the treatment of refractory advanced urothelial cancer. Cutaneous toxicity is well described but has not been correlated with response. In this retrospective single-center study, data from patients treated with more than one dose of EV between December 2017 and June 2022 were analyzed. Of 56 patients with a median age of 69 yr, 41 (73.2%) were male and 27 (48.2%) had any-grade skin toxicity. For all 51 patients evaluable by physician-assessed Response Evaluation Criteria in Solid Tumors (RECIST) criteria, the response rate was 41.2%. For those with cutaneous toxicity, the response rate was 57.7%; for those without cutaneous toxicity, it was 24.0% (p = 0.0145). All three patients with complete response experienced cutaneous toxicity, and two of these responses remain durable 5 and 24 mo off EV. The median starting weight and body mass index (BMI) were, respectively, 80.86 kg and 26.53 kg/m² among patients with cutaneous toxicity, and 69.37 kg and 23.29 kg/m² in patients without (p = 0.0129 and 0.0014, respectively). In this small dataset, EV-related cutaneous toxicity was more common in patients with higher weight and BMI at baseline, and was associated with disease response. Confirmation in prospective trials may confirm this association and lead to an important clinical biomarker of response.

Patient summary

We evaluated patients with urothelial cancer who were treated at our institution with enfortumab vedotin (EV). We found that patients who experienced the common side effect of any type of skin toxicity, such as rash or itching, were more likely to have improvement in their cancer from EV treatment than those who did not experience skin toxicity. Patients with higher weight and body mass index when starting EV tended to have more skin toxicity. We conclude that presence of skin toxicity might help doctors make decisions about how to manage the care of patients with EV in the future.

Antibody-Drug-Conjugates (ADC): A Novel Treatment Option in Urothelial Carcinoma

Antibody drug conjugates (ADC) are a new class of agents that have been expanding the spectrum of treatment options in metastatic urothelial carcinoma only recently. Preliminary data suggest that these compounds may have the potential even to replace current standard treatments as platinum-based chemotherapies. To this end, current and future preclinical and translational evaluation of novel treatment strategies should consider these novel compounds in addition to current standard options as well. In this context, the following article will provide an overview of this new class of agents, starting with general information on molecular structure and mode of action, clinical use of ADCs in urothelial carcinoma, and ending with considerations for designing preclinical and translational experiments implementing ADCs.

Two Cases of Exacerbation of Asthma during Treatment with Enfortumab Vedotin

Enfortumab vedotin is an antibody-drug conjugate against nectin-4 that is recently being used in the management of patients with urothelial carcinoma. The common adverse events include rashes, peripheral neuropathy, and hyperglycemia. Only a few cases of associated respiratory symptoms have been reported. Herein, we describe 2 patients with advanced urothelial carcinoma who experienced asthma exacerbation after initiating enfortumab vedotin treatment. Both patients improved with inhalation therapy. Since nectin-4 is expressed in the tracheal epithelium, its association with asthma is likely. This study highlights that clinicians should caution patients with a history of asthma against the worsening of respiratory symptoms when enfortumab vedotin is administered.

Complete Response to Enfortumab Vedotin in a Hemodialysis Patient with Metastatic Urothelial Carcinoma: A Case Report

Enfortumab vedotin (EV) is an antibody-drug conjugate and a promising agent for metastatic urothelial carcinoma (mUC). However, evaluations in end-stage renal disease patients undergoing hemodialysis are unreported. Here, we report such a case. A 74-year-old woman with mUC, on hemodialysis for complete urinary tract extirpation, was diagnosed with multiple pulmonary metastases after treatment with gemcitabine-carboplatin followed by pembrolizumab. As third-line therapy, she received a standard dose of EV. She achieved complete response after 2 cycles without grade 3 or higher adverse events, demonstrating the utility of EV in this setting.

TROP2 Expression Across Molecular Subtypes of Urothelial Carcinoma and Enfortumab Vedotin-resistant Cells

Sacituzumab govitecan (SG) is an antibody-drug conjugate (ADC) targeting TROP2, which has recently been approved for treatment-refractory metastatic urothelial cancer (UC). However, the variability of TROP2 expression across different bladder cancer (BC) subtypes, as well as after enfortumab vedotin (EV) exposure, remains unknown. Using gene expression data from four clinical cohorts with >1400 patient samples of muscle-invasive BC and a BC tissue microarray, we found that TROP2 mRNA and protein are highly expressed across basal, luminal, and stroma-rich subtypes, but depleted in the neuroendocrine subtype. In addition, TROP2 mRNA levels are correlated with NECTIN4 mRNA but are more highly expressed than NECTIN4 mRNA in patient cohorts and BC cell lines. Moreover, CRISPR/Cas9-mediated knockdown of TROP2 demonstrates that its expression is one factor governing SG sensitivity. After prolonged EV exposure, cells can downregulate NECTIN4, leading to EV resistance, but retain TROP2 expression and remain sensitive to SG, suggesting nonoverlapping resistance mechanisms to these ADCs. While our findings warrant further validation, they have significant implications for biomarker development, patient selection, and treatment sequencing in the clinic as well as clinical trial design and stratification for metastatic BC patients. PATIENT SUMMARY: In this report, we investigated the expression levels of the drug target TROP2 across different molecular subtypes of bladder cancer in multiple patient cohorts and cell lines. We found high levels of TROP2 in most subtypes except in the neuroendocrine subtype. Overall, TROP2 gene expression is higher than NECTIN4 gene expression, and cells resistant to enfortumab vedotin (EV), a NECTIN4-targeting antibody-drug conjugate, remain sensitive to sacituzumab govitecan (SG). Our findings suggest that SG may be effective across most bladder cancer subtypes, including the bladder cancers previously treated with EV.

Enfortumab vedotin-related pneumonitis is more common than expected and could lead to acute respiratory failure

PURPOSE

To analyse the incidence of pneumonitis related to enfortumab vedotin (EV) in patients with metastatic urothelial cell carcinoma (mUC).

METHODS

Patients with mUC who participated in two EV clinical trials in South Korea were analysed for the incidence and clinical course of EV-related pneumonitis through retrospective, independent review. The clinical characteristics and radiologic attributes of potential pneumonitis were identified and reviewed by the participating investigators and pulmonologists.

RESULTS

Between October 2018 and January 2020, 64 patients were enrolled in the EV-201 and EV-301 trials across eight institutions in South Korea and were treated with EV. Among them, 18 (28.1%) developed all-grade EV-related pneumonitis, from which 2 (11.1%) patients died. The median time between the last dosing of immunotherapy and the start of EV was 5.6 weeks (range, 0.71-143.1). The median time from the start of EV treatment to the onset of pneumonitis was 13 weeks (range, 2.7-51.0). Of the patients who developed pneumonitis, 7 (38.9%) were clinically asymptomatic. The most common radiologic finding was organising pneumonia (66.7%).

CONCLUSIONS

Although we could not rule out the relationship with prior immunotherapy administration, EV-related pneumonitis occurred in approximately 25% of the patients who had received EV in two prospective clinical trials, from which two died. Clinicians should closely monitor patients who have experienced immunotherapy treatment failure for the development of pneumonitis. A delay between initiating EV after termination of immunotherapy should be considered with caution.

An update on antibody-drug conjugates in urothelial carcinoma: state of the art strategies and what comes next

In recent years, considerable progress has been made in increasing the knowledge of tumour biology and drug resistance mechanisms in urothelial cancer. Therapeutic strategies have significantly advanced with the introduction of novel approaches such as immune checkpoint inhibitors and Fibroblast Growth Factor Receptor inhibitors. However, despite these novel agents, advanced urothelial cancer is often still progressive in spite of treatment and correlates with a poor prognosis. The introduction of antibody–drug conjugates consisting of a target-specific monoclonal antibody covalently linked to a payload (cytotoxic agent) is a novel and promising therapeutic strategy. In December 2019, the US Food and Drug Administration (FDA) granted accelerated approval to the nectin-4-targeting antibody–drug conjugate, enfortumab vedotin, for the treatment of advanced or metastatic urothelial carcinomas that are refractory to both immune checkpoint inhibitors and platinum-based treatment. Heavily pre-treated urothelial cancer patients reported a significant, 40% response to enfortumab vedotin while other antibody–drug conjugates are currently still under investigation in several clinical trials. We have comprehensively reviewed the available treatment strategies for advanced urothelial carcinoma and outlined the mechanism of action of antibody–drug conjugate agents, their clinical applications, resistance mechanisms and future strategies for urothelial cancer.

Nectin-4: a Novel Therapeutic Target for Skin Cancers

OPINION STATEMENT

Nectin-4 is a tumor-associated antigen that is highly expressed on various cancer cells, and it has been further proposed to have roles in tumor development and propagation ranging from cellular proliferation to motility and invasion. Nectin-4 blockade reduces tumor proliferation and induces apoptosis in several malignancies. Nectin-4 has been used as a potential target in antibody-drug conjugate (ADC) development. Enfortumab vedotin, an ADC against Nectin-4, has demonstrated efficacy against solid tumor malignancies. Enfortumab vedotin has received US Food and Drug Administration approval for treating urothelial cancer. Furthermore, the efficacy of ADCs against Nectin-4 against solid tumors other than urothelial cancer has been demonstrated in preclinical studies, and clinical trials examining the effects of enfortumab vedotin are ongoing. Recently, Nectin-4 was reported to be highly expressed in several skin cancers, including malignant melanoma, cutaneous squamous cell carcinoma, and extramammary Paget's disease, and involved in tumor progression and survival in retrospective studies. Nectin-4-targeted therapies and ADCs against Nectin-4 could therefore be novel therapeutic options for skin cancers. This review highlights current knowledge on Nectin-4 in malignant tumors, the efficacy of enfortumab vedotin in clinical trials, and the prospects of Nectin-4-targeted agents against skin cancers.

Outcomes of metastatic urothelial carcinoma following discontinuation of enfortumab-vedotin

BACKGROUND

Enfortumab vedotin (EV) is approved to treat metastatic urothelial carcinoma (mUC) following platinum and PD1/L1 inhibitors. Since the outcomes and patterns of therapy of patients following discontinuation of EV are unknown, we conducted a retrospective study to assess this issue.

METHODS

Data were retrospectively obtained from patients with mUC following discontinuation of EV after prior platinum-based chemotherapy and PD1/L1 inhibitors. Objective response rate (ORR) was evaluated in those who received therapy post-EV. Statistical analyses were performed to describe the overall survival (OS) and compare patient characteristics and outcomes of those who did or did not receive treatment post-EV.

RESULTS

Data were available for 63 patients from 6 institutions: 46 (73%) were male and median age was 68 years (range 43-83). The median OS was 32 weeks. Thirty-two patients (51%) received therapy after EV. The OS of those who did vs. did not receive post-EV therapy was significantly different (median 43.1 vs. 16.9 weeks, P = .015). Longer duration of prior EV therapy was associated with receipt of post-EV therapy (P = .0437) as well as OS in both the treated (P = .045) and untreated groups (P = .012). Objective response was observed in 3 of 32 patients (9.4%) who received therapy post-EV.

CONCLUSION

Outcomes of patients with mUC following discontinuation of EV are dismal and only 51% received therapy after discontinuation of EV. This study identifies benchmarks for the interpretation of activity of new agents following EV and raises the hypothesis for duration of EV as a potential prognostic factor following discontinuation of EV.

New and topics: enfortumab vedotin mechanisms of response and resistance in urothelial cancer - What do we understand so far?

Enfortumab vedotin (EV) was FDA approved in December 2019 for platinum- and checkpoint-refractory urothelial cancer based on an exceptional 44% response rate, and is currently approved for use after platinum and checkpoint inhibitor therapy. Enfortumab is an antibody-drug conjugate that targets Nectin-4, which is widely expressed in urothelial cancer. Despite this ample target, clinical benefit is not achieved by all patients, and mechanisms of treatment resistance are undescribed. Herein we summarize what is known to date regarding coorelative findings and subgroup analysis and EV response, including novel biopsy data in patients with tumor progression post EV.

Enfortumab vedotin to treat urothelial carcinoma

The antibody-drug conjugate enfortumab vedotin is a fully humanized monoclonal antibody targeting Nectin-4 linked to a microtubule-disrupting agent, monomethyl auristatin E, via a protease-cleavable maleimidocaproyl valine-citrulline linker. In this article, we provide a comprehensive review of the preclinical and clinical activity of enfortumab vedotin, which has been recently approved in the U.S. for the treatment of adult patients with locally advanced or metastatic urothelial carcinoma who have previously received a programmed cell death protein 1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) inhibitor as well as platinum-containing chemotherapy in the neoadjuvant/adjuvant, locally advanced or metastatic setting. Enfortumab vedotin is the first antibody-drug conjugate approved for patients with urothelial carcinoma.

Enfortumab Vedotin, a fully human monoclonal antibody against Nectin 4 conjugated to monomethyl auristatin E for metastatic urothelial Carcinoma

Introduction: The conventional management of most patients with metastatic urothelial carcinoma (UC) is platinum-based chemotherapy followed by immunotherapy. Erdafitinib is an option in post-platinum patients with activating mutations in fibroblast growth factor receptor (FGFR)-3 and -2. Salvage therapy with taxanes or vinflunine has demonstrated minimal efficacy. Enfortumab Vedotin (EV), a monoclonal antibody-drug conjugate (ADC) targeting nectin-4 is under investigation in patients with advanced UC. Areas covered: This review describes the epidemiology and unmet needs of patients with metastatic UC and is focused specifically on heavily treated patients. We explore the rationale for targeting nectin 4 and the clinical development of EV; efficacy and safety data from the completed phase I and II studies are examined. Ongoing trials to definitively assess clinical outcomes in comparison to current therapy and trials exploring EV in combination are also highlighted. Expert opinion: There is an unmet need for new therapies in most patients with advanced UC and who progress after platinum and immunotherapy. EV has shown promising efficacy and safety in this population in phase 1 and 2 trials including those with poor prognostic factors such as liver metastases. Ongoing trials exploring this agent in combination will continue to advance the treatment of UC.