Atezolizumab in Platinum-treated Locally Advanced or Metastatic Urothelial Carcinoma: Outcomes by Prior Number of Regimens

The heterogeneity of cellular metabolism in the tumour microenvironment of hepatocellular carcinoma with portal vein tumour thrombus

Given the growing interest in the metabolic heterogeneity of hepatocellular carcinoma (HCC) and portal vein tumour thrombus (PVTT). This study comprehensively analysed the metabolic heterogeneity of HCC, PVTT, and normal liver samples using multi-omics combinations. A single-cell RNA sequencing dataset encompassing six major cell types was obtained for integrated analysis. The optimal subtypes were identified using cluster stratification and validated using spatial transcriptomics and fluorescent multiplex immunohistochemistry. Then, a combined index based meta-cluster was calculated to verify its prognostic significance using multi-omics data from public cohorts. Our study first depicted the metabolic heterogeneity landscape of non-malignant cells in HCC and PVTT at multiomics levels. The optimal subtypes interpret the metabolic characteristics of PVTT formation and development. The combined index provided effective predictions of prognosis and immunotherapy responses. Patients with a higher combined index had a relatively poor prognosis (p <0.001). We also found metabolism of polyamines was a key metabolic pathway involved in conversion of metabolic heterogeneity in HCC and PVTT, and identified ODC1 was significantly higher expressed in PVTT compared to normal tissue (p =0.03). Our findings revealed both consistency and heterogeneity in the metabolism of non-malignant cells in HCC and PVTT. The risk stratification based on cancer-associated fibroblasts and myeloid cells conduce to predict prognosis and guide treatment. This offers new directions for understanding disease development and immunotherapy responses.

Exploring the Immunoresponse in Bladder Cancer Immunotherapy

Bladder cancer (BC) represents a wide spectrum of diseases, ranging from recurrent non-invasive tumors to advanced stages that require intensive treatments. BC accounts for an estimated 500,000 new cases and 200,000 deaths worldwide every year. Understanding the biology of BC has changed how this disease is diagnosed and treated. Bladder cancer is highly immunogenic, involving innate and adaptive components of the immune system. Although little is still known of how immune cells respond to BC, immunotherapy with bacillus Calmette-Guérin (BCG) remains the gold standard in high-risk non-muscle invasive BC. For muscle-invasive BC and metastatic stages, immune checkpoint inhibitors targeting CTLA-4, PD-1, and PD-L1 have emerged as potent therapies, enhancing immune surveillance and tumor cell elimination. This review aims to unravel the immune responses involving innate and adaptive immune cells in BC that will contribute to establishing new and promising therapeutic options, while reviewing the immunotherapies currently in use in bladder cancer.

Challenges Coexist with Opportunities: Spatial Heterogeneity Expression of PD-L1 in Cancer Therapy

Cancer immunotherapy using anti-programmed death-ligand 1 (PD-L1) antibodies has been used in various clinical applications and achieved certain results. However, such limitations as autoimmunity, tumor hyperprogression, and overall low patient response rate impede its further clinical application. Mounting evidence has revealed that PD-L1 is not only present in tumor cell membrane but also in cytoplasm, exosome, or even nucleus. Among these, the dynamic and spatial heterogeneous expression of PD-L1 in tumors is mainly responsible for the unsatisfactory efficacy of PD-L1 antibodies. Hence, numerous studies focus on inhibiting or degrading PD-L1 to improve immune response, while a comprehensive understanding of the molecular mechanisms underlying spatial heterogeneity of PD-L1 can fundamentally transform the current status of PD-L1 antibodies in clinical development. Herein, the concept of spatial heterogeneous expression of PD-L1 is creatively introduced, encompassing the structure and biological functions of various kinds of PD-L1 (including mPD-L1, cPD-L1, nPD-L1, and exoPD-L1). Then an in-depth analysis of the regulatory mechanisms and potential therapeutic targets of PD-L1 is provided, seeking to offer a solid basis for future investigation. Moreover, the current status of agents is summarized, especially small molecular modulators development directed at these new targets, offering a novel perspective on potential PD-L1 therapeutics strategies.

Immunotherapy for advanced or metastatic urothelial carcinoma

BACKGROUND

Immune checkpoint inhibitors are increasingly important in the treatment algorithm for locally advanced and metastatic bladder cancer. Numerous ongoing studies are investigating these agents as first- and second-line therapies, both alone and in combination with chemotherapy or in a maintenance therapy setting.

OBJECTIVES

To assess the effects of immune checkpoint inhibitors compared to chemotherapy as first- and second-line treatment of advanced or metastatic urothelial carcinoma.

SEARCH METHODS

We performed a comprehensive search including the Cochrane Library, MEDLINE, Embase, three other databases, several trial registers, other sources of gray literature, and conference proceedings, with no restrictions on language of publication. We limited the search period to run from 2000 until August 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) using immunotherapy versus chemotherapy and would have considered non-randomized trials in the absence of randomized trial data. Participants had locally advanced inoperable (cT4b or N+, or both) or metastatic (M1) (or both) urothelial carcinoma of the bladder or upper urinary tract. We excluded studies of people in whom immunotherapy was used in combination with chemotherapy or in a surveillance setting.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies for inclusion and abstracted data from included studies. We performed statistical analyses using a random-effects model and interpreted them according to the Cochrane Handbook for Systematic Reviews of Interventions. We used GRADE guidance to rate the certainty of evidence on a per-outcome basis.

MAIN RESULTS

We included five RCTs and identified seven single-armed studies. The RCTs included 3572 participants comparing immunotherapy versus chemotherapy for the treatment of locally advanced and metastatic bladder cancer. First-line therapy Immunotherapy probably has little to no effect on the risk of death from any cause when used as first-line therapy compared to chemotherapy (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.87 to 1.07; I2 = 0%; 3 studies, 2068 participants; moderate-certainty evidence). This corresponds to 750 deaths per 1000 participants with chemotherapy and 11 fewer (45 fewer to 26 more) deaths per 1000 participants with immunotherapy at 36 months. Immunotherapy probably has little to no effect on health-related quality of life (mean difference (MD) 4.10, 95% CI 3.83 to 4.37; 1 study, 393 participants; moderate-certainty evidence), when assuming a minimal clinically important difference (MCID) of at least 6 points (using the Functional Assessment of Cancer Therapy - Bladder [FACT-BL] tool; scale 0 to 156 with higher scores representing better quality of life). Immunotherapy probably reduces adverse events grade 3 to 5 (RR 0.47, 95% CI 0.29 to 0.75; I2 = 97%; 3 studies, 2046 participants; moderate-certainty evidence). This corresponds to 908 grade 3 to 5 adverse events per 1000 participants with chemotherapy, with 481 fewer (644 fewer to 227 fewer) grade 3 to 5 adverse events per 1000 participants with immunotherapy. We found no evidence for the outcome time to death from bladder cancer. Immunotherapy probably increases the risk of time to disease progression (HR 1.33, 95% CI 1.17 to 1.50; I2 = 0%; 2 studies, 1349 participants; moderate-certainty evidence). This corresponds to 660 events per 1000 participants with chemotherapy and 102 more (57 more to 152 more) events per 1000 participants with immunotherapy at 36 months. Immunotherapy may reduce discontinuations due to adverse effects (RR 0.47, 95% CI 0.20 to 1.10; I2 = 94%; 3 studies, 2046 participants; low-certainty evidence). This corresponds to 338 discontinuations per 1000 participants with chemotherapy and 179 fewer (271 fewer to 34 more) discontinuations per 1000 participants with immunotherapy. Second-line therapy Immunotherapy may reduce the risk of death from any cause when used as second-line therapy (HR 0.72, 95% CI 0.63 to 0.81; I2 = 0%; 2 studies, 1473 participants; low-certainty evidence). This corresponds to 920 deaths per 1000 participants with chemotherapy (vinflunine, paclitaxel, docetaxel) and 59 fewer (95 fewer to 28 fewer) deaths per 1000 participants with immunotherapy at 36 months. Immunotherapy may have little to no effect on health-related quality of life when compared to chemotherapy (MD 4.82, 95% CI -3.11 to 12.75; I2 = 85%; 2 studies, 727 participants; low-certainty evidence), assuming an MCID of at least 10 points (using the EORTC QLQ tool; scale 0 to 100 with higher scores representing better quality of life). Immunotherapy may reduce adverse events grade 3 to 5 in participants undergoing second-line therapy (RR 0.89, 95% CI 0.81 to 0.97; I2 = 9%; 2 studies, 1423 participants; low-certainty evidence). This corresponds to 630 grade 3 to 5 adverse events per 1000 participants with chemotherapy and 76 fewer (126 fewer to 25 fewer) grade 3 to 5 adverse events per 1000 participants with immunotherapy. We found no evidence for the outcome of time to death from bladder cancer. We are very uncertain if immunotherapy reduces the risk of disease progression (HR 0.99, 95% CI 0.84 to 1.16; I2 = 0%; 2 studies, 1473 participants; very low-certainty evidence). Immunotherapy may reduce discontinuations due to adverse events in participants undergoing second-line therapy (RR 0.35, 95% CI 0.17 to 0.72; I2 = 69%; 2 studies, 1473 participants; low-certainty evidence). This corresponds to 110 discontinuations per 1000 participants with chemotherapy and 72 fewer (91 fewer to 31 fewer) discontinuations per 1000 participants with immunotherapy.

AUTHORS' CONCLUSIONS

Compared to chemotherapy, immunotherapy for treating advanced or metastatic urothelial carcinoma probably has little to no effect on the risk of death from any cause when used as first-line therapy. Still, it may reduce the risk of death from any cause when used as second-line therapy. Health-related quality of life for participants receiving first- and second-line therapy does not appear to be affected by immunotherapy. Immunotherapy probably reduces or may reduce adverse events grade 3 to 5 when used as first- and second-line therapy, respectively.

FGFR3 mutation characterization identifies prognostic and immune-related gene signatures in bladder cancer

BACKGROUND

Immunotherapy and FGFR3-targeted therapy play an important role in the management of locally advanced and metastatic bladder cancer (BLCA). Previous studies indicated that FGFR3 mutation (mFGFR3) may be involved in the alterations of immune infiltration, which may affect the priority or combination of these two treatment regimes. However, the specific impact of mFGFR3 on the immunity and how FGFR3 regulates the immune response in BLCA to affect prognosis remain unclear. In this study, we aimed to elucidate the immune landscape associated with mFGFR3 status in BLCA, screen immune-related gene signatures with prognostic value, and construct and validate a prognostic model.

METHODS

ESTIMATE and TIMER were used to assess the immune infiltration within tumors in the TCGA BLCA cohort based on transcriptome data. Further, the mFGFR3 status and mRNA expression profiles were analyzed to identify immune-related genes that were differentially expressed between patients with BLCA with wild-type FGFR3 or mFGFR3 in the TCGA training cohort. An FGFR3-related immune prognostic score (FIPS) model was established in the TCGA training cohort. Furthermore, we validated the prognostic value of FIPS with microarray data in the GEO database and tissue microarray from our center. Multiple fluorescence immunohistochemical analysis was performed to confirm the relationship between FIPS and immune infiltration.

RESULTS

mFGFR3 resulted in differential immunity in BLCA. In total, 359 immune-related biological processes were enriched in the wild-type FGFR3 group, whereas none were enriched in the mFGFR3 group. FIPS could effectively distinguish high-risk patients with poor prognosis from low-risk patients. The high-risk group was characterized by a higher abundance of neutrophils; macrophages; and follicular helper, CD4, and CD8 T-cells than the low-risk group. In addition, the high-risk group exhibited higher expression of PD-L1, PD-1, CTLA-4, LAG-3, and TIM-3 than the low-risk group, indicating an immune-infiltrated but functionally suppressed immune microenvironment. Furthermore, patients in the high-risk group exhibited a lower mutation rate of FGFR3 than those in the low-risk group.

CONCLUSIONS

FIPS effectively predicted survival in BLCA. Patients with different FIPS exhibited diverse immune infiltration and mFGFR3 status. FIPS might be a promising tool for selecting targeted therapy and immunotherapy for patients with BLCA.

Predictive value of molecular subtypes and APOBEC3G for adjuvant chemotherapy in urothelial bladder cancer

OBJECTIVE

Although targeted approaches have become available in second- and third-line settings, platinum-based chemotherapy remains the standard first-line treatment for advanced muscle-invasive bladder cancer (MIBC). Therefore, the prediction of platinum resistance is of utmost clinical importance.

METHODS

In this study, we established a routine compatible method for the molecular classification of MIBC samples according to various classification systems and applied this method to evaluate the impact of subtypes on survival after adjuvant chemotherapy. This retrospective study included 191 patients with advanced MIBC (pT≥3 or pN+) who underwent radical cystectomy, with or without adjuvant chemotherapy. A 48-gene panel and classifier rule set were established to determine molecular subtypes according to TCGA, MDA, LundTax, and Consensus classifications. Additionally, 12 single platinum-predictive candidate genes were assessed. The results were correlated with patients' clinicopathological and follow-up data and were validated using independent data sets.

RESULTS

Our final evaluation of 159 patients demonstrated better survival in the luminal groups for those who received chemotherapy compared with those who did not. In contrast, no such differences were observed in basal subtypes. The use of chemotherapy was associated with better survival in patients with high APOBEC3G expression (p < 0.002). This association was confirmed using an independent data set of patients who received neoadjuvant platinum therapy.

CONCLUSIONS

The proposed method robustly replicates the most commonly used transcriptome-based subtype classifications from paraffin-embedded tissue samples. The luminal, but not basal, molecular subtypes had the greatest benefit from adjuvant platinum therapy. We identified and validated APOBEC3G as a novel predictive marker for platinum-treated patients.

Gemcitabine–Paclitaxel Chemotherapy for Patients with Advanced Urothelial Cancer Refractory to Cisplatin-Based Chemotherapy: Predictive Role of PGK1 for Treatment Response to Cytotoxic Chemotherapy

An investigation of alternatives to immune checkpoint inhibitors for advanced urothelial cancer (aUC), with biologic information, is urgently needed. Clinical data for 53 patients who received gemcitabine–paclitaxel therapy (GP) as 2nd-line chemotherapy for aUC refractory to platinum-based chemotherapy were retrospectively reviewed. The efficacy and tolerability of GP were evaluated, and the predictive value of phosphoglycerate kinase 1 (PGK1) immunostained in surgical specimens was investigated for treatment outcomes in 1st- and 2nd-line chemotherapy. GP was associated with an objective response rate of 35.8% and a median overall survival duration of 12.3 months. Multivariate analysis showed that PS2 and 1st- and 2nd-line non-response are independent predictors of worse progression-free survival and that PS2 and 1st-line non-response are independent predictors of worse overall survival. Adverse events were manageable, and no therapy-related deaths occurred. Non-response rates to 1st-line chemotherapy were significantly higher in patients with a high expression of PGK1 in the nucleus than in those with low expression (p = 0.006). Our study demonstrates the efficacy and tolerability of 2nd-line GP for patients with aUC who are refractory to platinum-based chemotherapy. Moreover, PGK1 in the nucleus was predictive values for resistance to platinum-based chemotherapy in aUC.

Local Investigators Significantly Overestimate Overall Response Rates Compared to Blinded Independent Central Reviews in Uncontrolled Oncology Trials: A Comprehensive Review of the Literature

Several drugs gained market authorization based on the demonstration of improved progression-free survival (PFS), adopted as a primary endpoint in Phase 3 clinical trials. In addition, an increasing number of drugs have been granted accelerated approval, and sometimes regular approval, by the main regulatory agencies based on the evaluation of the overall response rate in Phase 1 and 2 clinical trials. However, while the overall survival is an unbiased measure of drug efficacy, these outcomes rely on the assessment of radiological images and patients’ categorization using standardized response criteria. The evaluation of these outcomes may be influenced by subjective factors, particularly when the analysis is performed locally. In fact, blinding of treatment is not always possible in modern oncology trials. Therefore, a blinded independent central review is often adopted to overcome the problem of expectation bias associated with local investigator assessments. In this regard, we have recently observed that local investigators tend to overestimate the overall response rate in comparison to central reviewers in Phase 2 clinical trials, whereas we did not find any significant evaluation bias between local investigators and central reviews when considering progression-free survival in both Phase 2 and 3 trials. In the present article, we have tried to understand the reasons behind this discrepancy by reviewing the available evidence in the literature. In addition, a further analysis of Phase 2 and 3 clinical trials that included the evaluation of both endpoints showed that local investigators significantly overestimate overall response rates compared to blinded independent central reviews in uncontrolled oncology trials.

Checkpoint Inhibition in Bladder Cancer: Clinical Expectations, Current Evidence, and Proposal of Future Strategies Based on a Tumor-Specific Immunobiological Approach

Simple Summary

In contrast with other strategies, immunotherapy is a treatment aimed at empowering the patient’s immune system in order to increase immunity and the response against cancer. Recently, a new class of drugs, immune checkpoint inhibitors, has shown potential in increasing treatment chances for patients with bladder cancers, improving their survival. However, predicting the response to immune checkpoint inhibition is important, since only a group of patients develop a good response. Biomarkers to predict the response to checkpoint inhibition must identify tumors’ and patients’ specific profiles. This study reviews the current knowledge on this most relevant clinical topic, focusing on bladder cancer, going from basic science to ongoing clinical trials and available clinical evidence. Finally, a critical analysis of published data is provided, and an original panel of biomarkers, able to select the right patients for treatments, based on patient-specific immune profiling, is proposed.

Abstract

In contrast with other strategies, immunotherapy is the only treatment aimed at empowering the immune system to increase the response against tumor growth. Immunotherapy has a role in the treatment of bladder cancer (BC) due to these tumors’ high tumor mutational burden (TMB) and mostly prominent immune infiltrate. The therapy or combination has to be adjusted to the tumor’s immunobiology. Recently, a new class of immunotherapeutic agents, immune checkpoint inhibitors (ICI), has shown potential in increasing treatment chances for patients with genitourinary cancers, improving their oncological outcomes. The clinical efficacy of ICI has been shown in both the first-line treatment of cisplatin-ineligible patients, with programmed death ligand 1 (PD-L1)-positive tumors (atezolizumab, pembrolizumab), and in second-line settings, for progression after platinum-based chemotherapy (atezolizumab, pembrolizumab, and nivolumab for FDA and EMA; durvalumab and avelumab for FDA alone). Predicting the response to ICI is important since only a subset of patients undergoing ICI therapy develop a concrete and lasting response. Most of the patients require a different therapy or therapy combination to achieve tumor control. The cancer immunity cycle provides a conceptual framework to assist therapy selection. Biomarkers to predict response to ICI must identify where the cancer immunity cycle is disrupted. We reviewed the current knowledge on ICI treatment in BC, going from basic science to current data and available clinical evidence. Secondly, a critical analysis of published data is provided, and an original panel of biomarkers able to predict response to ICI treatment, based on tumor-specific immune profiling, is proposed.

SAUL, a single-arm study of atezolizumab for chemotherapy-pretreated locally advanced or metastatic carcinoma of the urinary tract: outcomes by key baseline factors, PD-L1 expression and prior platinum therapy

BACKGROUND

The impact of pretreatment factors on immune checkpoint inhibition in platinum-refractory advanced urothelial cancer (aUC) deserves further evaluation. The aim was to study the association of Bellmunt risk factors, time from last chemotherapy (TFLC), previous therapy and PD-L1 expression with atezolizumab efficacy in platinum-refractory aUC.

PATIENTS AND METHODS

This was a post-hoc analysis of patients who had received prior cisplatin or carboplatin in the prospective, single-arm, phase IIIb SAUL study (NCT02928406). Patients were treated with 3-weekly atezolizumab 1200 mg intravenously. The primary outcome was overall survival (OS). Relationships were analysed using Cox regression and long-rank test.

RESULTS

Of 997 patients in SAUL, 969 were eligible for this analysis. The number of Bellmunt risk factors was associated with OS (P < 0.001); median OS (mOS) for 0, 1 and 2-3 risk factors was 17.9, 8.9 and 3.3 months, respectively. Significant associations were also observed between OS and TFLC (P < 0.001), programmed death-ligand 1 (PD-L1) expression (P = 0.002), and prior perioperative chemotherapy (P = 0.013); mOS was 6.97 versus 11.63 months for TFLC ≤6 versus >6 months, 7.75 versus 11.6 months for PD-L1 expression on <1% of tumour-infiltrating immune cells (ICs) (IC0)/expression on 1% to <5% of tumour-infiltrating ICs (IC1) versus expression on ≥5% of tumour-infiltrating ICs (IC2/3) and 10.2 versus 7.8 months for prior versus no prior perioperative chemotherapy, respectively. The type of platinum compound and number of previous treatment lines were not associated with outcomes.

CONCLUSIONS

Post-platinum atezolizumab is active in aUC, irrespective of previous platinum compound and lines of therapy. Bellmunt risk stratification, PD-L1 expression, TFLC and perioperative chemotherapy were identified as prognostic factors for OS with second-line atezolizumab, indicating the need for novel prognostic signatures for immunotherapy-treated patients with aUC.

Detection of Molecular Signatures of Homologous Recombination Deficiency in Bladder Cancer

PURPOSE

Poly (ADP ribose)-polymerase (PARP) inhibitors are approved for use in breast, ovarian, prostate, and pancreatic cancers, which are the solid tumor types that most frequently have alterations in key homologous recombination (HR) genes, such as BRCA1/2. However, the frequency of HR deficiency (HRD) in other solid tumor types, including bladder cancer, is less well characterized.

EXPERIMENTAL DESIGN

Specific DNA aberration profiles (mutational signatures) are induced by HRD, and the presence of these "genomic scars" can be used to assess the presence or absence of HRD in a given tumor biopsy even in the absence of an observed alteration of an HR gene. Using whole-exome and whole-genome data, we measured various HRD-associated mutational signatures in bladder cancer.

RESULTS

We found that a subset of bladder tumors have evidence of HRD. In addition to a small number of tumors with biallelic BRCA1/2 events, approximately 10% of bladder tumors had significant evidence of HRD-associated mutational signatures. Increased levels of HRD signatures were associated with promoter methylation of RBBP8, which encodes CtIP, a key protein involved in HR.

CONCLUSIONS

A subset of bladder tumors have genomic features suggestive of HRD and therefore may be more likely to benefit from therapies such as platinum agents and PARP inhibitors that target tumor HRD.

Clinical therapies and nano drug delivery systems for urinary bladder cancer

Bladder cancer is the 10^th most commonly occurring malignancy worldwide with a 75% of 5-year survival rate, while it ranks 13^th among the deaths occurring due to cancer. The majority of bladder cancer cases are diagnosed at an early stage and 70% are of non-invasive grade. However, 70% of these cases develop chemoresistance and progress to the muscle invasive stage. Conventional chemotherapy treatments are unsuccessful in curbing chemoresistance, bladder cancer progression while having an adverse side effect, which is mainly due to off-target drug distribution. Therefore, new drug delivery strategies, new therapeutics and therapies or their combination are being explored to develop better treatments. In this regard, nanotechnology has shown promise in the targeted delivery of therapeutics to bladder cancer cells. This review discusses the recent discovery of new therapeutics (chemotherapeutics, immunotherapeutic, and gene therapies), recent developments in the delivery of therapeutics using nano drug delivery systems, and the combination treatments with FDA-approved therapies, i.e., hyperthermia and photodynamic therapy. We also discussed the potential of other novel drug delivery systems that are minimally explored in bladder cancer. Lastly, we discussed the clinical status of therapeutics and therapies for bladder cancer. Overall, this review can provide a summary of available treatments for bladder cancer, and also provide opportunities for further development of drug delivery systems for better management of bladder cancer.

Safety and Activity of Programmed Cell Death 1 Versus Programmed Cell Death Ligand 1 Inhibitors for Platinum-Resistant Urothelial Cancer: A Meta-Analysis of Published Clinical Trials

Background

Programmed death 1/ligand 1 (PD-1/L1) inhibitors have acceptable antitumor activity in patients with platinum-resistant urothelial cancer (UC). However, the reliability and comparability of the antitumor activity, safety profiles and survival outcomes of different immune checkpoint inhibitors are unknown. Our objective was to compare the clinical efficacy and safety of anti–PD-1/PD-L1 therapies in platinum-resistant UC patients.

Methods

We reviewed the published trials from the PubMed, Embase and Cochrane Library databases up to August 2020. A well-designed mirror principle strategy to screen and pair trial characteristics was used to justify indirect comparisons. The primary end point was the objective response rate (ORR). The safety profile and survival outcomes were also evaluated. The restricted mean survival time (RMST) up to 12 months was calculated.

Results

Eight studies including 1,666 advanced or metastatic UC patients (1,021 patients with anti–PD-L1 treatment and 645 patients with anti–PD-1 treatment) met the study criteria. The ORRs of anti–PD-1 and PD-L1 therapy were 22% (95% CI, 18%–25%) and 15% (95% CI, 13%–17%) with all studies combined. The proportions of the treated population with a confirmed objective response (I² = 0; P = 0.966; HR, 1.60; 95% CI, 1.23–2.07; P < 0.001) and disease control (I² = 30.6%; P = 0.229; HR, 1.35; 95% CI, 1.10–1.66; P = 0.004) were higher with anti–PD-1 therapy than with anti–PD-L1 therapy. The treatment-related adverse events (AEs) (I² = 78.3%; P = 0.003; OR, 1.09; 95% CI, 0.65–1.84; P = 0.741) and grade 3–5 treatment-related AEs (I² = 68.5%; P = 0.023; OR, 1.69; 95% CI, 0.95–3.01; P = 0.074) of anti–PD-1 therapy were comparable to those of anti–PD-L1 therapy. The RMST values at the 12-month follow-up were 9.4 months (95% CI,: 8.8–10.0) for anti–PD-1 therapy and 9.3 months (95% CI, 8.8–9.7) for anti–PD-L1 therapy (z = 0.26, P = 0.794). There was no significant difference between patients in the anti–PD-1 and anti–PD-L1 groups (12-month overall survival (OS): 43% versus 42%, P = 0.765. I² = 0; P = 0.999; HR, 0.95; 95% CI, 0.83–1.09; P = 0.474).

Conclusions

The results of our systematic comparison suggest that anti–PD-1 therapy exhibits better antitumor activity than anti–PD-L1 therapy, with comparable safety profiles and survival outcomes. These findings may contribute to enhanced treatment awareness in patients with platinum-resistant 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.

Immune checkpoint inhibition in muscle-invasive and locally advanced bladder cancer

PURPOSE OF REVIEW

Immune-checkpoint inhibitors (CPIs) have been implemented in the treatment algorithm of metastatic urothelial cancer as they have shown higher and more sustained responses compared with conventional second-line chemotherapy. Recently, several clinical trials have reported on CPIs in earlier disease stages such as muscle-invasive bladder cancer (MIBC). This review summarizes ongoing clinical trials and results from early phase clinical trials in muscle invasive and locally advanced bladder cancer.

RECENT FINDINGS

In phase II clinical trials, neoadjuvant use of CPIs as mono and combination therapy, in patients with MIBC planned for radical cystectomy, has shown promising pathological complete response rates. Whether this will translate in survival benefit remains to be assessed. Combination of CPIs and conventional chemotherapy or other targeted agents promises to increase the efficacy of perioperative systemic therapy with potentially additive toxicities. Recently, preclinical models of combined trimodal therapy with CPIs delivered the proof of principle leading to several ongoing trials in this setting.

SUMMARY

First results of clinical trials evaluating CPIs in MIBC demonstrate very promising results that warrant further investigation as they could revolutionize management of MIBC in the near future. The trend and hope are toward higher rates of safe and sustained bladder preservation.

Local Investigators Significantly Overestimate Overall Response Rates Compared to Blinded Independent Central Reviews in Phase 2 Oncology Trials

The overall response rate (ORR) is a largely adopted outcome measure in early-phase oncology trials. ORR is highly relevant in cancer drug development at the time of deciding whether to move to confirmatory phase 3 trials; moreover, ORR is gaining increasing relevance in fast-track registration procedures. No systematic analysis has been conducted so far to investigate whether a discrepancy exists between ORR assessed by local investigators and those assessed by blinded reviewers in phase 2 oncology trials. In this study, we carried out a search in the clinicaltrials.gov and EudraCT databases, looking at the trials reporting the results of both investigator-assessed and independently-assessed ORR. A discrepancy index was obtained by calculating the ratio of each investigator-assessed ORR on the corresponding independently assessed ORR, so that a discrepancy index >1 indicates that the investigator was "more optimistic," whereas a discrepancy index <1 indicates the opposite. We also analyzed different subgroups (by tumor type, by drug type, by year). Twenty trials met the search criteria; in some cases, >1 comparison was conducted in the trial, so that the total number of comparisons analyzed was 33. The estimated mean discrepancy index was 1.175 (95% confidence interval, 1.083-1.264; n = 33). In conclusion, local investigators significantly overestimate ORR compared to paired blinded reviewers in phase 2 oncology trials. This may represent a risk in drug development, when deciding whether to move to confirmatory, more expensive phase 3 trials. Blinded independent central review should be used in ORR assessment if a more conservative estimate of treatment efficacy is required, as in the case of fast-track drug developments leading to accelerated approvals of cancer therapies.

Expression of PD-L1 for predicting response to immune checkpoint inhibitors in metastatic urothelial carcinoma: a systematic review and meta-analysis

Background

We conducted this meta-analysis and systematic literature review to study the ability of PD-L1 to predict objective response in patients with urothelial cancer treated with PD-1/PD-L1 inhibitors.

Methods

Relevant studies of PD-1 or PD-L1 inhibitors in urothelial cancer that reported objective response rate (orr) based on PD-L1 expression status in PubMed, embase, and the Cochrane Library were retrieved. Efficacy of PD-L1 expression status in predicting orr and the efficacy, safety of PD-1 and PD-L1 drugs were analyzed.

Results

Studies were divided into ≥1%, ≥5%, and ≥25% based on PD-L1 positivity threshold, and the patients were grouped into PD-L1 positive and negative. In all 3 expression thresholds, patients with positive PD-L1 expression were more likely to experience an objective response [≥1% threshold odds ratio (or): 1.74; 95% confidence interval (ci): 1.20 to 2.53; ≥5% threshold or: 2.74; 95% ci: 2.01 to 3.724; ≥25% threshold or: 7.13; 95% ci: 2.38 to 21.40] in comparison with patients with negative PD-L1 expression. Of the 3 thresholds, the ≥25% threshold was better in predicting orr (1.74 vs. 2.93 vs. 7.13; p < 0.0001). The ≥1% PD-L1 threshold had a relatively high sensitivity in predicting orr; the ≥5% PD-L1 threshold was better for specificity. Sensitivity was higher at the ≥25% threshold than at the other two thresholds, but specificity was lower. Further, we found that there is no statistically significant difference in efficacy between PD-1 and PD-L1 drugs.

Conclusions

Urothelial cancer patients with PD-L1 positive expression responded better than PD-L1 negative patients did, and a threshold of ≥5% or greater for PD-L1 expression might predict positive clinical response.

Identification of a Synthetic Lethal Relationship between Nucleotide Excision Repair Deficiency and Irofulven Sensitivity in Urothelial Cancer

PURPOSE

Cisplatin-based chemotherapy is a first-line treatment for muscle-invasive and metastatic urothelial cancer. Approximately 10% of bladder urothelial tumors have a somatic missense mutation in the nucleotide excision repair (NER) gene, ERCC2, which confers increased sensitivity to cisplatin-based chemotherapy. However, a significant subset of patients is ineligible to receive cisplatin-based therapy due to medical contraindications, and no NER-targeted approaches are available for platinum-ineligible or platinum-refractory ERCC2-mutant cases.

EXPERIMENTAL DESIGN

We used a series of NER-proficient and NER-deficient preclinical tumor models to test sensitivity to irofulven, an abandoned anticancer agent. In addition, we used available clinical and sequencing data from multiple urothelial tumor cohorts to develop and validate a composite mutational signature of ERCC2 deficiency and cisplatin sensitivity.

RESULTS

We identified a novel synthetic lethal relationship between tumor NER deficiency and sensitivity to irofulven. Irofulven specifically targets cells with inactivation of the transcription-coupled NER (TC-NER) pathway and leads to robust responses in vitro and in vivo, including in models with acquired cisplatin resistance, while having minimal effect on cells with intact NER. We also found that a composite mutational signature of ERCC2 deficiency was strongly associated with cisplatin response in patients and was also associated with cisplatin and irofulven sensitivity in preclinical models.

CONCLUSIONS

Tumor NER deficiency confers sensitivity to irofulven, a previously abandoned anticancer agent, with minimal activity in NER-proficient cells. A composite mutational signature of NER deficiency may be useful in identifying patients likely to respond to NER-targeting agents, including cisplatin and irofulven.See related commentary by Jiang and Greenberg, p. 1833.

Different patterns of treatment-related adverse events of programmed cell death-1 and its ligand-1 inhibitors in different cancer types: A meta-analysis and systemic review of clinical trials

Programmed cell death receptor-1 and its ligand-1 (PD-1/PD-L1) inhibitors have been applied to many cancers, but the difference of treatment-related adverse events (AEs) across cancer types remains unknown. We performed a meta-analysis and systemic review to compare the incidences of commonly reported all-grade AEs across cancer types and found that the most frequent AEs were fatigue, rash/pruritus, loss of appetite/nausea and diarrhea. However, each cancer type also had its higher incidences of AEs involving a relevant system, such as melanoma with epidermal AEs (rash, diarrhea and enterocolitis), lung cancer with dyspnea and pneumonitis, digestive system cancers with amylase and lipase elevation; and renal cell and urothelial cancer with kidney injury (creatinine elevation and proteinuria). However, the incidence of hepatitis did not follow the pattern to show a difference. We did another comparison between PD-1 and PD-L1 inhibitors in lung cancer and urothelial cancer respectively, and found that the risk of most AEs did not differ much, except for more hypothyroidism in PD-1 inhibitors, and more kidney injury in PD-L1 inhibitors. Besides possible immunological mechanisms for treatment-related AEs, the influence of previous radiotherapy and the clinical characteristics of the diseases themselves should also be considered and is worth further investigation. With the result of this meta-analysis, clinicians could estimate the risk of certain AE in certain cancer type, to make treatment options and to customize monitor strategies.

Biomarkers for Immune Checkpoint Inhibitor-Mediated Tumor Response and Adverse Events

In the last decade, inhibitors targeting immune checkpoint molecules such as cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death 1 (PD-1), and programmed cell death-ligand 1 (PD-L1) brought about a major paradigm shift in cancer treatment. These immune checkpoint inhibitors (ICIs) improved the overall survival of a variety of cancer such as malignant melanoma and non-small lung cancer. In addition, numerous clinical trials for additional indication of ICIs including adjuvant and neo-adjuvant therapies are also currently ongoing. Therefore, more and more patients will receive ICIs in the future. However, despite the improved outcome of the cancer treatment by ICIs, the efficacy remains still limited and tumor regression have not been obtained in many cancer patients. In addition, treatment with ICIs is also associated with substantial toxicities, described as immune-related adverse events (irAEs). Therefore, biomarkers to predict tumor response and occurrence of irAEs by the treatment with ICIs are required to avoid overtreatment of ICIs and minimize irAEs development. Whereas, numerous factors have been reported as potential biomarkers for tumor response to ICIs, factors for predicting irAE have been less reported. In this review, we show recent advances in the understanding of biomarkers for tumor response and occurrence of irAEs in cancer patients treated with ICIs.

Consultation on UTUC, Stockholm 2018: aspects of treatment

Purpose

To provide an overview of treatment modalities for management of upper tract urothelial carcinoma (UTUC).

Methods

In accordance with the standards for a scoping review, data presentation and discussion at the Consultation on UTUC in Stockholm, 6–7 September 2018, consensus was reached on the latest and most important treatment recommendations for UTUC. Using Pubmed, Web of Science, and Embase, publications were selected based on quality, clinical relevance, and level of evidence.

Results

Kidney-sparing surgery should be attempted for low-grade UTUC. Radical nephroureterectomy with bladder cuff excision is first option for high-grade disease. Post-operative bladder instillation of chemotherapy should be offered after RNU to reduce intravesical recurrence rate. Identification of tumor grade and stage is crucial when selecting treatment. Ureteroscopic management of low-grade and non-invasive UTUC achieves disease-free survival similar to that offered by radical nephroureterectomy but seems to be a risk factor for intravesical recurrence. Lymphadenectomy appears important for high-risk disease, although the therapeutic benefit needs further validation. There is little evidence supporting use of Bacillus Calmette–Guérin (BCG) and mitomycin C as monotherapy and adjuvant treatment in UTUC. A randomized clinical trial has indicated that platin-based chemotherapy for invasive UTUC improves disease-free survival, suggesting that adjuvant chemotherapy should be considered standard care for ≥ T2 N0–3M0 disease.

Conclusions

Risk stratification assessment is feasible and mandatory in UTUC. Identification of tumor grade and stage is essential for optimal treatment selection. Kidney-sparing surgery should be offered in low-risk disease, whereas radical nephroureterectomy and adjuvant chemotherapy should be considered in high-risk disease.

RNAi-Mediated PD-L1 Inhibition for Pancreatic Cancer Immunotherapy

The recent past has seen impressive progress in the treatment of various malignancies using immunotherapy. One of the most promising approaches involves immune checkpoint inhibitors. However, the clinical results with these agents have demonstrated variability in the response. Pancreatic cancer, in particular, has proven resistant to initial immunotherapy approaches. Here, we describe an alternative strategy that relies on combining gemcitabine and a novel programmed death-ligand 1 (PD-L1) inhibitor, termed MN-siPDL1. MN-siPDL1 incorporates small interfering RNA against PD-L1 (siPDL1) conjugated to a magnetic nanocarrier (MN). We show that noninvasive magnetic resonance imaging (MRI) could be used to monitor therapeutic response. Combination therapy consisting of gemcitabine and MN-siPDL1 in a syngeneic murine pancreatic cancer model resulted in a significant reduction in tumor growth and an increase in survival. Following optimization, a 90% reduction in tumor volume was achieved 2 weeks after the beginning of treatment. Whereas 100% of the control animals had succumbed to their tumors by week 6 after the beginning of treatment, there was no mortality in the experimental group by week 5, and 67% of the experimental animals survived for 12 weeks. This method could provide therapeutic benefit against an intractable disease for which there are no effective treatments and which is characterized by a mere 1% 5-year survival.

Gemcitabine and docetaxel as second-line chemotherapy in elderly patients with metastatic urothelial carcinoma: a retrospective analysis

Background

The objective of this study was to evaluate the efficacy of a combination of gemcitabine and docetaxel (GD) as a second-line treatment for elderly patients with metastatic urothelial carcinoma (mUC).

Patients and methods

A total of 122 patients with mUC who were previously treated with platinum-based chemotherapy received second-line GD therapy from July 2010 to June 2016. This consisted of 800 mg/m² gemcitabine and 40 mg/m² docetaxel on days 1 and 8 in each 21-day cycle. Using pooled cumulative data, we divided patients into the following three groups based on age: <65 years (Group A), from 65 to 74 years (Group B), and ≥75 years (Group C), and then the data were retrospectively analyzed. All patients were evaluated for treatment-related toxicities and assessed at every cycle by imaging studies. Kaplan-Meier curves were used for survival and recurrence analyses. Furthermore, potential prognostic factors for progression-free survival (PFS) and overall survival (OS) were assessed via univariate and multivariate Cox regression analyses.

Results

The median follow-up period was 8.2 months (range: 2.1-100). The median number of treatment cycles was three (range: 1-16) in Group A, three (1-15) in Group B, and two (1-11) in Group C. The objective response rate was not significantly different between the three groups. In addition, PFS and OS from the start of second-line GD therapy were also not significantly different. According to univariate and multivariate analyses of the second-line GD-treated cohort, a good performance status was the only prognostic factor for PFS and OS. In Group C, myelosuppression including predominant neutropenia and anemia, fatigue, and nausea were the main common adverse events. However, the incidence of neutropenia and a reduction in platelets were not significantly different between the three groups. Treatment-related deaths did not occur in this study.

Conclusion

In this study, GD combination therapy as a second-line treatment for mUC resulted in favorable tumor responses and few treatment-related toxicities, even among elderly patients.

Immune checkpoint inhibitors for urothelial carcinoma

Urothelial carcinoma (UC), originating in the bladder or upper urinary tract, is the most common histological type of cancer. Currently, platinum-based cytotoxic chemotherapy is the standard treatment for metastatic UC (mUC) and the preferred treatment option in the perioperative (neoadjuvant and/or adjuvant) setting of muscle invasive bladder cancer (MIBC). In addition, intravesical bacillus Calmette-Guerin immunotherapy or chemotherapy is applied as the adjuvant therapeutic option in non-muscle invasive bladder cancer (NMIBC) after transurethral resection, to prevent recurrence and progression. In recent years, with an increased understanding of cancer immunobiology, systemic immunotherapies targeting immune checkpoint inhibition has been explored and clinically used in the area of UC. The programmed cell death 1 receptor (PD-1) and its ligand (PD-L1) are important negative regulators of immune activity, preventing the destruction of normal tissues and autoimmunity. To date, five immune checkpoint inhibitors blocking PD-1 (pembrolizumab, nivolumab) or PD-L1 (atezolizumab, durvalumab, and avelumab) have been approved by the United States Food and Drug Administration (US-FDA) for first- or second-line use in mUC, based on durable therapeutic response and manageable safety profiles observed in relevant clinical trials. In addition, the clinical use of several immune checkpoint inhibitors is currently being tested for MIBC and NMIBC. In this article, we review the current and ongoing clinical trials, regarding immune checkpoint inhibitors, being conducted in various clinical settings of UC, including mUC, MIBC, and NMIBC.

Aerosol Immunotherapy with or without Cisplatin for metastatic lung cancer non-small cell lung cancer disease: In vivo Study. A more efficient combination

Lung cancer is the leading cause of cancer death after prostate cancer for males and breast cancer for females. There are novel therapies in the past five years such as; tyrosine kinase inhibitors and most recently in the last two years immunotherapy. Immunotherapy is currently being investigated if it can be administered alone or in combination. Previously we have investigated whether immunotherapy compounds can be produced as aerosols, and in the current study we investigated the safety and efficiency independently of the programmed death-ligand 1. The aerosol administration of both cisplatin and nivolumab is possible. The combination of the two drugs has a synergistic effect and therefore should be considered an option. Time of administration for immunotherapy is also very important.

New research in bladder cancer, ASCO-GU 2017

N/A