Molecular residual disease detection in resected, muscle-invasive urothelial cancer with a tissue-based comprehensive genomic profiling-informed personalized monitoring assay

Introduction

Circulating tumor DNA (ctDNA) detection postoperatively may identify patients with urothelial cancer at a high risk of relapse. Pragmatic tools building off clinical tumor next-generation sequencing (NGS) platforms could have the potential to increase assay accessibility.

Methods

We evaluated the widely available Foundation Medicine comprehensive genomic profiling (CGP) platform as a source of variants for tracking of ctDNA when analyzing residual samples from IMvigor010 (ClinicalTrials.gov identifier NCT02450331), a randomized adjuvant study comparing atezolizumab with observation after bladder cancer surgery. Current methods often involve germline sampling, which is not always feasible or practical. Rather than performing white blood cell sequencing to filter germline and clonal hematopoiesis (CH) variants, we applied a bioinformatic approach to select tumor (non-germline/CH) variants for molecular residual disease detection. Tissue-informed personalized multiplex polymerase chain reaction-NGS assay was used to detect ctDNA postsurgically (Natera).

Results

Across 396 analyzed patients, prevalence of potentially actionable alterations was comparable with the expected prevalence in advanced disease (13% FGFR2/3, 20% PIK3CA, 13% ERBB2, and 37% with elevated tumor mutational burden ≥10 mutations/megabase). In the observation arm, 66 of the 184 (36%) ctDNA-positive patients had shorter disease-free survival [DFS; hazard ratio (HR) = 5.77; 95% confidence interval (CI), 3.84-8.67; P < 0.0001] and overall survival (OS; HR = 5.81; 95% CI, 3.41-9.91; P < 0.0001) compared with ctDNA-negative patients. ctDNA-positive patients had improved DFS and OS with atezolizumab compared with those in observation (DFS HR = 0.56; 95% CI, 0.38-0.83; P = 0.003; OS HR = 0.66; 95% CI, 0.42-1.05). Clinical sensitivity and specificity for detection of postsurgical recurrence were 58% (60/103) and 93% (75/81), respectively.

Conclusion

We present a personalized ctDNA monitoring assay utilizing tissue-based FoundationOne® CDx CGP, which is a pragmatic and potentially clinically scalable method that can detect low levels of residual ctDNA in patients with resected, muscle-invasive bladder cancer without germline sampling.

Precision Medicine in Bladder Cancer: Present Challenges and Future Directions

Bladder cancer (BC) is characterized by significant histopathologic and molecular heterogeneity. The discovery of molecular pathways and knowledge of cellular mechanisms have grown exponentially and may allow for better disease classification, prognostication, and development of novel and more efficacious noninvasive detection and surveillance strategies, as well as selection of therapeutic targets, which can be used in BC, particularly in a neoadjuvant or adjuvant setting. This article outlines recent advances in the molecular pathology of BC with a better understanding and deeper focus on the development and deployment of promising biomarkers and therapeutic avenues that may soon make a transition into the domain of precision medicine and clinical management for patients with BC.

Emerging monoclonal antibody therapies in the treatment of metastatic urothelial carcinoma

INTRODUCTION

The treatment landscape for advanced-stage, unresectable or metastatic urothelial carcinoma (mUC) has shifted dramatically over a short period of time, with new therapeutic agents available for clinical use. However, despite these recent advances in the field, mUC continues to be a disease with significant morbidity and mortality and remains generally incurable. While platinum-based therapy remains the backbone of therapy, many patients are ineligible for chemotherapy or have failed initial chemotherapy treatment. In post-platinum treated patients, immunotherapy and antibody drug conjugates have provided incremental advances, but agents with better therapeutic index guided by precision medicine are needed.

AREAS COVERED

This article covers the available monoclonal antibody therapies in mUC excluding immunotherapy and antibody drug conjugates. Included are a review of data utilizing monoclonal antibodies targeting VEG-F, HER-2, FGFR, and KIR-2 in the setting of mUC. A literature search from 6/2022- 9/2022 was performed utilizing PubMed with key terms including urothelial carcinoma, monoclonal antibody, VEG-F, HER-2, FGFR.

EXPERT OPINION

Often used in combination with immunotherapy or other therapeutic agents, monoclonal antibody therapies have exhibited efficacy in mUC in early trials. Upcoming clinical trials will further explore their full clinical utility in treating mUC patients.

Concurrent durvalumab and radiation therapy (DUART) followed by adjuvant durvalumab in patients with localized urothelial cancer of bladder: results from phase II study, BTCRC-GU15-023

BACKGROUND

Patients with bladder cancer (BC) who are cisplatin ineligible or have unresectable disease have limited treatment options. Previously, we showed targeting programmed death-ligand 1 (PD-L1) with durvalumab (durva) and radiation therapy (RT) combination was safe in BC. We now report results from a phase II study evaluating the toxicity and efficacy of durva and RT in localized BC.

METHODS

This is a single-arm, multi-institutional phase II study; N=26. Enrolled patients had pure or mixed urothelial BC (T2-4 N0-2 M0) with unresectable tumors and were unfit for surgery or cisplatin ineligible. Patients received durva concurrently with RT ×7 weeks, followed by adjuvant durva × 1 year.

PRIMARY ENDPOINTS

(A) progression-free survival (PFS) at 1 year and (B) disease control rate (DCR) post adjuvant durva. Key secondary endpoints: (A) complete response (CR) post durvaRT (8 weeks), (B) overall survival (OS), (C) PFS and (D) toxicity. Correlative studies included evaluation of baseline tumor and blood (baseline, post durvaRT) for biomarkers.

RESULTS

Median follow-up was 27 months. Evaluable patients: 24/26 post durvaRT, 22/26 for DCR post adjuvant durva, all patients for PFS and OS. Post adjuvant durva, DCR was seen in 72.7%, CR of 54.5%. 1-year PFS was 71.5%, median PFS was 21.8 months. 1-year OS was 83.8%, median OS was 30.8 months. CR at 8 weeks post durvaRT was 62.5%. Node positive (N+) patients had similar median PFS and OS. DurvaRT was well tolerated. Grade ≥3 treatment-related adverse events: anemia, high lipase/amylase, immune-nephritis, transaminitis, dyspnea (grade 4-COPD/immune), fatigue, rash, diarrhea and scleritis. No difference in outcome was observed with PD-L1 status of baseline tumor. Patients with CR/PR or SD had an increase in naïve CD4 T cells, a decrease in PD-1+CD4 T cells at baseline and an increase in cytokine-producing CD8 T cells, including interferon gamma (IFNγ) producing cells, in the peripheral blood.

CONCLUSION

Durva with RT followed by adjuvant durva was safe with promising efficacy in localized BC patients with comorbidities, including N+ patients. Larger randomized studies, like S1806 and EA8185, are needed to evaluate the efficacy of combining immunotherapy and RT in BC.

TRIAL REGISTRATION NUMBER

NCT02891161.

A multi-omic single cell sequencing approach to develop a CD8 T cell specific gene signature for anti-PD1 response in solid tumors

Immune checkpoint blockade (ICB) has led to durable clinical responses in multiple cancer types. However, biomarkers that identify which patients are most likely to respond to ICB are not well defined. Many putative biomarkers developed from a small number of samples often fail to maintain their predictive status in larger validation cohorts. We show across multiple human malignancies and syngeneic murine tumor models that neither pretreatment T cell receptor (TCR) clonality nor changes in clonality after ICB correlate with response. Dissection of tumor infiltrating lymphocytes pre- and post-ICB by paired single-cell RNA sequencing and single-cell TCR sequencing reveals conserved and distinct transcriptomic features in expanded TCR clonotypes between anti-PD1 responder and nonresponder murine tumor models. Overall, our results indicate a productive anti-tumor response is agnostic of TCR clonal expansion. Further, we used single-cell transcriptomics to develop a CD8⁺ T cell specific gene signature for a productive anti-tumor response and show the response signature to be associated with overall survival (OS) on nivolumab monotherapy in CheckMate-067, a phase 3 clinical trial in metastatic melanoma. These results highlight the value of leveraging single-cell assays to dissect heterogeneous tumor and immune subsets and define cell-type specific transcriptomic biomarkers of ICB response.

Putative Biomarkers of Clinical Benefit With Pembrolizumab in Advanced Urothelial Cancer: Results from the KEYNOTE-045 and KEYNOTE-052 Landmark Trials

PURPOSE

In an exploratory analysis, we investigated the association between programmed death ligand 1 (PD-L1), tumor mutational burden (TMB), T-cell-inflamed gene expression profile (TcellinfGEP), and stromal signature with outcomes of pembrolizumab in urothelial carcinoma (UC).

PATIENTS AND METHODS

Patients with advanced UC received first-line pembrolizumab 200 mg every 3 weeks in the single-arm phase II KEYNOTE-052 trial (NCT02335424) and salvage pembrolizumab 200 mg every 3 weeks or chemotherapy (paclitaxel/docetaxel/vinflunine) in the randomized phase III KEYNOTE-045 trial (NCT02256436). The association of each biomarker (continuous variable) with objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) was evaluated using logistic regression (ORR) and Cox PH (PFS, OS), adjusted for ECOG PS; nominal P values were calculated without multiplicity adjustment (one-sided, pembrolizumab; two-sided, chemotherapy). Significance was prespecified at α = 0.05.

RESULTS

In KEYNOTE-052, PD-L1, TMB, and TcellinfGEP were significantly associated with improved outcomes; stromal signature was significantly associated with worse outcomes. In KEYNOTE-045, although findings for TMB and TcellinfGEP with pembrolizumab were consistent with those of KEYNOTE-052, PD-L1 was not significantly associated with improved outcomes, nor was stromal signature associated with worse outcomes with pembrolizumab; chemotherapy was not associated with outcomes in a consistent manner for any of the biomarkers. Hazard ratio (HR) estimates at prespecified cutoffs showed an advantage for pembrolizumab versus chemotherapy regardless of PD-L1 or TMB, with a trend toward lower HRs in the combined positive score ≥10 and the TMB ≥175 mutation/exome subgroup. For TcellinfGEP, PFS and OS HRs were lower in the TcellinfGEP-nonlow subgroup regardless of treatment.

CONCLUSIONS

Multiple biomarkers characterizing the tumor microenvironment may help predict response to pembrolizumab monotherapy in UC, and potential clinical utility of these biomarkers may be context-dependent.

The Evolution of Immune Checkpoint Inhibitors in Advanced Urothelial Carcinoma

Simple Summary

Urothelial carcinoma is an aggressive cancer with a high risk of metastatic progression. Chemotherapy plays a key role in the management of metastatic urothelial carcinoma, with, however, no possibility of cure. Immune checkpoint inhibitors have significantly improved the outcomes of patients, delaying progression of disease and improving quality of life. However, many questions remain concerning the optimal use of immunotherapy in urothelial carcinoma: When to start? Which biomarker of sensitivity/resistance to use? Which of the available options will increase the efficacy of immune checkpoint inhibitors? We review the mechanisms of immune checkpoint inhibitors as well as the current management of patients with metastatic urothelial carcinoma in the era of immunotherapy.

Abstract

Urothelial carcinoma is an aggressive cancer and development of metastases remains a challenge for clinicians. Immune checkpoint inhibitors (ICIs) are significantly improving the outcomes of patients with metastatic urothelial cancer (mUC). These agents were first used in monotherapy after failure of platinum-based chemotherapy, but different strategies explored the optimal use of ICIs in a first-line metastatic setting. The “maintenance” strategy consists of the introduction of ICIs in patients who experienced benefit from first-line chemotherapy in a metastatic setting. This allows an earlier use of ICIs, without waiting for disease progression. We review the optimal management of mUC in the era of ICIs, based on the key clinical messages arising from the pivotal trials.

Immune-Checkpoint Inhibitors in Advanced Bladder Cancer: Seize the Day

Background: In advanced bladder cancer (BCa), platinum-based chemotherapy represents the first-choice treatment. In the last ten years, immune checkpoint inhibitors (ICIs) have changed the therapeutic landscape of many solid tumors. Our review aims to summarize the main findings regarding the clinical use of ICIs in advanced BCa. Methods: We searched PubMed, Embase, and Cochrane databases, and conference abstracts from international congresses (ASCO, ESMO, ASCO GU) for clinical trials, focusing on ICIs as monotherapy and combinations in metastatic BCa. Results: 18 studies were identified. ICIs targeting PD1 (nivolumab, pembrolizumab), PD-L1 (avelumab, atezolizumab, durvalumab), and CTLA4 (ipilimumab, tremelimumab) were used. Survival outcomes have been improved by second-line ICIs, whereas first-line results are dismal. Avelumab maintenance in patients obtaining disease control with chemotherapy has achieved the highest survival rates. Conclusions: ICIs improve survival after platinum-based chemotherapy. Avelumab maintenance represents a new practice-changing treatment. The combinations of ICIs and other compounds, such as FGFR-inhibitors, antibody-drug conjugates, and anti-angiogenic drugs, represent promising therapeutic approaches. Biomarkers with predictive roles and sequencing strategies are warranted for best patient selection.

Avelumab maintenance in advanced urothelial carcinoma: biomarker analysis of the phase 3 JAVELIN Bladder 100 trial

In a recent phase 3 randomized trial of 700 patients with advanced urothelial cancer (JAVELIN Bladder 100; NCT02603432 ), avelumab/best supportive care (BSC) significantly prolonged overall survival relative to BSC alone as maintenance therapy after first-line chemotherapy. Exploratory biomarker analyses were performed to identify biological pathways that might affect survival benefit. Tumor molecular profiling by immunohistochemistry, whole-exome sequencing and whole-transcriptome sequencing revealed that avelumab survival benefit was positively associated with PD-L1 expression by tumor cells, tumor mutational burden, APOBEC mutation signatures, expression of genes underlying innate and adaptive immune activity and the number of alleles encoding high-affinity variants of activating Fcγ receptors. Pathways connected to tissue growth and angiogenesis might have been associated with reduced survival benefit. Individual biomarkers did not comprehensively identify patients who could benefit from therapy; however, multi-parameter models incorporating genomic alteration, immune responses and tumor growth showed promising predictive utility. These results characterize the complex biologic pathways underlying survival benefit from immune checkpoint inhibition in advanced urothelial cancer and suggest that multiple biomarkers might be needed to identify patients who would benefit from treatment.

Prognostic and Predictive Factors in Advanced Urothelial Carcinoma Treated with Immune Checkpoint Inhibitors: A Review of the Current Evidence

In recent years, the treatment landscape of urothelial carcinoma has significantly changed due to the introduction of immune checkpoint inhibitors (ICIs), which are the standard of care for second-line treatment and first-line platinum-ineligible patients with advanced disease. Despite the overall survival improvement, only a minority of patients benefit from this immunotherapy. Therefore, there is an unmet need to identify prognostic and predictive biomarkers or models to select patients who will benefit from ICIs, especially in view of novel therapeutic agents. This review describes the prognostic and predictive role, and clinical readiness, of clinical and tumour factors, including new molecular classes, tumour mutational burden, mutational signatures, circulating tumour DNA, programmed death-ligand 1, inflammatory indices and clinical characteristics for patients with urothelial cancer treated with ICIs. A classification of these factors according to the levels of evidence and grades of recommendation currently indicates both a prognostic and predictive value for ctDNA and a prognostic relevance only for concomitant medications and patients' characteristics.

Immune Checkpoint Inhibitors for Genitourinary Cancers: Treatment Indications, Investigational Approaches and Biomarkers

Cancers of the genitourinary (GU) tract are common malignancies in both men and women and are a major source of morbidity and mortality. Immune checkpoint inhibitors (ICI) targeting CTLA-4, PD-1 or PD-L1 have provided clinical benefit, particularly in renal cell and urothelial carcinoma, and have been incorporated into standard of care treatment in both localized and metastatic settings. However, a large fraction of patients do not derive benefit. Identification of patient and tumor-derived factors which associate with response have led to insights into mechanisms of response and resistance to ICI. Herein, we review current approvals and clinical development of ICI in GU malignancies and discuss exploratory biomarkers which aid in personalized treatment selection.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of urothelial cancer

A number of immunotherapies have been developed and adopted for the treatment of urothelial cancer (encompassing cancers arising from the bladder, urethra, or renal pelvis). For these immunotherapies to positively impact patient outcomes, optimal selection of agents and treatment scheduling, especially in conjunction with existing treatment paradigms, is paramount. Immunotherapies also warrant specific and unique considerations regarding patient management, emphasizing both the prompt identification and treatment of potential toxicities. In order to address these issues, the Society for Immunotherapy of Cancer (SITC) convened a panel of experts in the field of immunotherapy for urothelial cancer. The expert panel developed this clinical practice guideline (CPG) to inform healthcare professionals on important aspects of immunotherapeutic treatment for urothelial cancer, including diagnostic testing, treatment planning, immune-related adverse events (irAEs), and patient quality of life (QOL) considerations. The evidence- and consensus-based recommendations in this CPG are intended to give guidance to cancer care providers treating patients with urothelial cancer.

TERT promoter mutations and other prognostic factors in patients with advanced urothelial carcinoma treated with an immune checkpoint inhibitor

BACKGROUND

Immune checkpoint inhibitors (ICI) can achieve durable responses in a subset of patients with locally advanced or metastatic urothelial carcinoma (aUC). The use of tumor genomic profiling in clinical practice may help suggest biomarkers to identify patients most likely to benefit from ICI.

METHODS

We undertook a retrospective analysis of patients treated with an ICI for aUC at a large academic medical center. Patient clinical and histopathological variables were collected. Responses to treatment were assessed for all patients with at least one post-baseline scan or clear evidence of clinical progression following treatment start. Genomic profiling information was also collected for patients when available. Associations between patient clinical/genomic characteristics and objective response were assessed by logistic regression; associations between the characteristics and progression-free survival (PFS) and overall survival (OS) were examined by Cox regression. Multivariable analyses were performed to identify independent prognostic factors.

RESULTS

We identified 119 aUC patients treated with an ICI from December 2014 to January 2020. Genomic profiling was available for 78 patients. Overall response rate to ICI was 29%, and median OS (mOS) was 13.4 months. Favorable performance status at the start of therapy was associated with improved OS (HR 0.46, p=0.025) after accounting for other covariates. Similarly, the presence of a TERT promoter mutation was an independent predictor of improved PFS (HR 0.38, p=0.012) and OS (HR 0.32, p=0.037) among patients who had genomic profiling available. Patients with both a favorable performance status and a TERT promoter mutation had a particularly good prognosis with mOS of 21.1 months as compared with 7.5 months in all other patients (p=0.03).

CONCLUSIONS

The presence of a TERT promoter mutation was an independent predictor of improved OS in a cohort of aUC patients treated with an ICI who had genomic data available. Most of the clinical and laboratory variables previously shown to be prognostic in aUC patients treated with chemotherapy did not have prognostic value among patients treated with an ICI. Genomic profiling may provide important prognostic information and affect clinical decision making in this patient population. Validation of these findings in prospective patient cohorts is needed.

Avelumab first-line maintenance in locally advanced or metastatic urothelial carcinoma: Applying clinical trial findings to clinical practice

Although urothelial carcinoma (UC) is considered a chemotherapy-sensitive tumor, progression-free survival and overall survival (OS) are typically short following standard first-line (1L) platinum-containing chemotherapy in patients with locally advanced or metastatic disease. Immune checkpoint inhibitors (ICIs) have antitumor activity in UC and favorable safety profiles compared with chemotherapy; however, trials of 1L ICI monotherapy or chemotherapy + ICI combinations have not yet shown improved OS vs chemotherapy alone. In addition to direct cytotoxicity, chemotherapy has potential immunogenic effects, providing a rationale for assessing ICIs as switch-maintenance therapy. In the JAVELIN Bladder 100 phase 3 trial, avelumab administered as 1L maintenance with best supportive care (BSC) significantly prolonged OS vs BSC alone in patients with locally advanced or metastatic UC that had not progressed with 1L platinum-containing chemotherapy (median OS, 21.4 vs 14.3 months; hazard ratio, 0.69 [95% CI, 0.56-0.86]; P = 0.001). Efficacy benefits were seen across various subgroups, including recipients of 1L cisplatin- or carboplatin-based chemotherapy, patients with PD-L1+ or PD-L1- tumors, and patients with diverse characteristics. Results from JAVELIN Bladder 100 led to the approval of avelumab as 1L maintenance therapy for patients with locally advanced or metastatic UC that has not progressed with platinum-containing chemotherapy. Avelumab 1L maintenance is also included as a standard of care in treatment guidelines for advanced UC with level 1 evidence. This review summarizes the data that supported these developments and discusses practical considerations for administering avelumab maintenance in clinical practice, including patient selection and treatment management.

Immune Checkpoint Inhibitors in Urothelial Carcinoma: Recommendations for Practical Approaches to PD-L1 and Other Potential Predictive Biomarker Testing

Simple Summary

The predominant histologic type of bladder cancer is urothelial carcinoma (UC). Programmed cell death-ligand 1 (PD-L1) expression levels in UC tumors help clinicians determine which patients are more likely to respond to immuno-oncology (IO) therapies; as such, the harmonization of PD-L1 testing in evaluating patients is increasingly important. A series of international workshops, involving renowned pathologists and oncologists, were held to develop best practice approaches to PD-L1 testing in UC. It was agreed that robust control of analytical standards is required to obtain quality PD-L1 results and that interpretation and reporting of PD-L1 require clear inter-clinician communication. Recommendations for the best practices for PD-L1 testing in UC are provided. A PD-L1 test request form for pathology laboratories was also developed and included here, encouraging communication between clinicians and pathologists, and ensuring fast and high-quality test results. Novel biomarkers being evaluated for immuno-oncology agents in UC are also briefly discussed.

Abstract

Immuno-oncology (IO) agents (anti–programmed cell death 1 (PD-1) and anti–programmed cell death-ligand 1 (PD-L1)) are approved as first- and second-line treatments for metastatic UC. PD-L1 expression levels in UC tumors help clinicians determine which patients are more likely to respond to IO therapies. Assays for approved IO agents use different antibodies, immunohistochemical protocols, cutoffs (defining “high” vs. “low” PD-L1 expression), and scoring algorithms. The robust control of pre-analytical and analytical standards is needed to obtain high-quality PD-L1 results. To better understand the status and perspectives of biomarker-guided patient selection for anti–PD-1 and anti–PD-L1 agents in UC, three workshops were held from December 2018 to December 2019 in Italy, Malaysia, and Spain. The primary goal was to develop recommendations for best practice approaches to PD-L1 testing in UC. Recommendations pertaining to the interpretation and reporting of the results of PD-L1 assays from experienced pathologists and oncologists from around the globe are included. A test request form for pathology laboratories was developed as a critical first step for oncologists/urologists to encourage communication between clinicians and pathologists, ensuring fast and high-quality test results. In this era of personalized medicine, we briefly discuss novel biomarkers being evaluated for IO agents in UC.

Coming of Age of Immunotherapy of Urothelial Cancer

Following platinum-based regimens becoming the reference standard of care, it has taken almost four decades to find a systemic treatment that improved overall survival in metastatic urothelial tumors. Single-agent immune checkpoint inhibitors have not only improved overall survival but also the quality of life of patients with metastatic urothelial tumors after failure of platinum-based regimens and as a maintenance therapy after four to six cycles of standard first-line chemotherapy. In addition, very promising data are emerging when single-agent immunotherapy is offered as adjuvant or neoadjuvant treatment for patients with muscle-invasive disease and also in the non-muscle-invasive setting. There is an extensive debate about the role of PD-L1 expression as a reliable biomarker to predict the activity of immune-based regimens. Furthermore, the lack of consensus concerning its utility means that there is a need for more and better tools to identify patients who are likely to benefit from these novel approaches. The field of urothelial tumors now additionally exploits novel antibody-drug conjugates and fibroblast growth factor-receptor inhibitors that are being tested in combination with immunotherapy. This added complexity contributes to an enormous increase in the challenges that will be faced shortly.

Practice change in the management of metastatic urothelial carcinoma after ASCO 2020

Metastatic urothelial carcinoma (mUC) is an incurable and aggressive disease. In the past decades there have been few effective treatment options that have impacted the prognosis of mUC patients. However, in the last few years, several drugs have emerged as new treatment choices that are changing the therapeutic landscape of mUC. Immune checkpoint inhibitors (ICIs) and targeted agents are useful treatment strategies that have been incorporated into our clinical practice. Nevertheless, cisplatin-based chemotherapy is still the standard of care in the first-line of metastatic disease. The results of the JAVELIN Bladder 100 phase 3 trial were presented at ASCO 2020, this trial evaluated the role of avelumab, an ICI, as maintenance therapy in patients who had not progressed after first-line platinum-based chemotherapy. The trial met its primary endpoint demonstrating an overall survival benefit with avelumab maintenance. In addition, new drugs and combinations are being evaluated to improve the outcomes of second and subsequent lines. Fibroblast growth factor receptor (FGFR) inhibitors and immunotherapy combinations were some of the strategies presented at ASCO 2020 that have shown promising results. Finally, the development of predictive biomarkers that help us in the decision-making process will be one of the most important challenges in the next years.

Future Strategies Involving Immune Checkpoint Inhibitors in Advanced Urothelial Carcinoma

OPINION STATEMENT

Immune checkpoint inhibitors have importantly improved the outcome of patients with urothelial carcinoma. Different immune checkpoint inhibitors are currently approved and used in first- and second-line setting. The multiple agents currently approved in these setting make the choice sometimes difficult for clinicians. Furthermore, only a minority of patients present drastic response and long-term benefit with current immunotherapy. In this review, we describe the current use of immunotherapy in urothelial carcinoma but we also highlight the new strategies of treatment involving immune checkpoint inhibitors; we describe the place of immunotherapy with chemotherapy, targeted agents, and anti-angiogenic agents, incorporating the recent results presented at ASCO 2020. This review explores also the different action mechanisms of immune checkpoint inhibitors and the molecular rational to evaluate these agents in other strategies, such as maintenance and salvage strategies. The new advances in biomarker development are also presented.

Combination therapy in advanced urothelial cancer: the role of PARP, HER-2 and mTOR inhibitors

INTRODUCTION

Despite significant advances in the treatment of metastatic urothelial carcinoma, including the advent of immune checkpoint inhibitors, this disease is still challenging to treat and associated poor outcomes remain. Genomic characterization of advanced-stage urothelial carcinoma is widening the field of potential treatments due to the identification of novel biologic drivers.

AREAS COVERED

In this review, we explore the role of PARP, HER-2, and mTOR inhibitors in the therapeutic scenario of advanced urothelial carcinoma, as these pathways are frequently altered in urothelial carcinoma. We report ongoing clinical trials involving these agents, either in monotherapy or in combination with other compounds, highlighting the dynamic scenario of metastatic urothelial carcinoma treatment.

EXPERT OPINION

Several challenges need to be faced in the development of new potential therapeutic strategies, such as inter/intratumoral heterogeneity and the lack of validated biomarkers.