Pembrolizumab in the treatment of locally advanced or metastatic urothelial carcinoma: clinical trial evidence and experience

Current Landscape of Immune Checkpoint Inhibitors for Metastatic Urothelial Carcinoma: Is There a Role for Additional T-Cell Blockade?

Urothelial carcinoma (UC) is the most common form of bladder cancer (BC) and is the variant with the most immunogenic response. This makes urothelial carcinoma an ideal candidate for immunotherapy with immune checkpoint inhibitors. Key immune checkpoint proteins PD-1 and CTLA-4 are frequently expressed on T-cells in urothelial carcinoma. The blockade of this immune checkpoint can lead to the reactivation of lymphocytes and augment the anti-tumor immune response. The only immune checkpoint inhibitors that are FDA-approved for metastatic urothelial carcinoma target the programmed death-1 receptor and its ligand (PD-1/PD-L1) axis. However, the overall response rate and progression-free survival rates of these agents are limited in this patient population. Therefore, there is a need to find further immune-bolstering treatment combinations that may positively impact survival for patients with advanced UC. In this review, the current immune checkpoint inhibition treatment landscape is explored with an emphasis on combination therapy in the form of PD-1/PD-L1 with CTLA-4 blockade. The investigation of the current literature on immune checkpoint inhibition found that preclinical data show a decrease in tumor volumes and size when PD-1/PD-L1 is blocked, and similar results were observed with CTLA-4 blockade. However, there are limited investigations evaluating the combination of CTLA-4 and PD-1/PD-L1 blockade. We anticipate this review to provide a foundation for a deeper experimental investigation into combination immune checkpoint inhibition therapy in metastatic urothelial carcinoma.

Undertreatment in patients with advanced urothelial cancer: systematic literature review and meta-analysis

Aim: To assess rates of no systemic treatment (NST), attrition across lines of therapy, and factors influencing treatment selection in patients with locally advanced or metastatic urothelial cancer (la/mUC). Methods: Systematic literature review to identify real-world studies reporting NST or attrition rates in la/mUC from 2017-2022 (including data reported since 2015). Results: Of 2439 publications screened, 29 reported NST rates, ranging from 40-74% in eight European-based studies, 14-60% in 12 US-based studies, and 9-63% in nine studies in other locations (meta-analysis estimate, 39%). Factors associated with NST or no second-line therapy included older age, female sex, poor performance status, poor renal function and distant metastases. Conclusion: A substantial proportion of patients with la/mUC do not receive guideline-recommended treatment.

Outcomes of Patients with Advanced Urothelial Carcinoma after Anti-programmed Death-(ligand) 1 Therapy by Fibroblast Growth Factor Receptor Gene Alteration Status: An Observational Study

Background

Clinical outcomes of anti-programmed death‑(ligand) 1 (anti-PD-[L]1) therapy in patients with locally advanced or metastatic urothelial carcinoma (mUC) and fibroblast growth factor receptor alterations (FGFRa+) remain unclear; recent studies have reported either comparable or poorer outcomes versus patients without FGFR alterations (FGFRa-).

Objective

To analyze the outcomes of patients with mUC and any FGFRa (mutations or fusions) who received anti-PD-(L)1 therapy.

Design setting and participants

In this noninterventional, retrospective, multicenter study, clinical practice data were collected from FGFRa+/- patients who received prior immunotherapy between May 2018 and July 2019.

Outcome measurements and statistical analysis

Investigator‑determined overall response rate (ORR), disease control rate (DCR), and overall survival (OS) were assessed in multivariate and unadjusted analyses.

Results and limitations

Ninety-four patients (66% men; median age, 63 yr) with mUC and known FGFR status were included; 38 (40%) were FGFRa+ and 56 (60%) were FGFRa-. In FGFRa+ versus FGFRa- patients who received any line of anti-PD-(L)1 therapy (n = 92), ORR, DCR, and OS were 16% versus 26%, 29% versus 52% (relative risk: 1.14 [95% confidence interval {CI}, 0.92-1.40]; p = 0.3), and 8.57 versus 13.2 mo (hazard ratio [HR]: 1.33 [95% CI, 0.77-2.30]; p = 0.3), respectively. A multivariate analysis provided some evidence supporting shorter OS in FGFRa+ versus FGFRa- (any line of anti-PD-L[1] therapy; HR: 1.81 [95% CI, 0.99-3.31]; p = 0.054). Limitations include this study's retrospective nature and a potential selection bias from small sample size.

Conclusions

Some evidence of lower response rates and shortened OS following anti-PD-(L)1 therapy was observed in FGFRa+ patients. The phase 3 THOR study (NCT03390504) will prospectively compare FGFRa+ patients with advanced mUC treated with erdafitinib versus pembrolizumab.

Patient summary

Patients with metastatic urothelial carcinoma and prespecified fibroblast growth factor receptor alterations (FGFRa) potentially have worse clinical outcomes when treated with anti-PD-(L)1 therapy than those without FGFRa.

Case report: Complete response of a bladder cancer patient with multiple hepatic and pelvic metastases treated by nab-paclitaxel combined with sintilimab

This article described a patient with metastatic bladder cancer (mBC) who was successfully treated with nab-paclitaxel plus sintilimab. Localized muscle-invasive bladder cancer (MIBC) was discovered in a 56-year-old man who received radical cystectomy and platinum-based adjuvant chemotherapy. Eleven months after cystectomy, this patient developed numerous hepatic and pelvic metastases and progressed to mBC. The patient was given an anti-PD-1 antibody (sintilimab 200mg, q3w) in combination with Nab-paclitaxel (100mg, qw) for mBC. Complete remission (CR) was achieved after nine cycles of therapy, and the patient had no severe side effects during the treatment. The disease remained in CR after 41 months of follow-up. This case suggests that nab-paclitaxel combined with sintilimab is a safe and effective option in treatment of mBC.

Immune Checkpoint Inhibitors as a Neoadjuvant/Adjuvant Treatment of Muscle-Invasive Bladder Cancer: A Systematic Review

Simple Summary

Bladder cancer is the ninth most common cancer worldwide. Immune checkpoint inhibitors, a novel class of immunotherapy drugs that restore natural antitumoral immune activity, have been applied to improve the overall survival and to reduce the morbidity and mortality of bladder cancer both in neoadjuvant and adjuvant settings. However, some patients do not respond to checkpoint inhibitors. Consequently, the capability for identifying patients eligible for this type of immunotherapy represent one of the efforts of ongoing studies. We aim to summarize the most recent evidence on immune checkpoint inhibitors in neoadjuvant and adjuvant setting in the treatment of muscle-invasive bladder cancer.

Abstract

Bladder cancer is the ninth most common cancer worldwide. Over 75% of non-muscle invasive cancer patients require conservative local treatment, while the remaining 25% of patients undergo radical cystectomy or radiotherapy. Immune checkpoint inhibitors represent a novel class of immunotherapy drugs that restore natural antitumoral immune activity via the blockage of inhibitory receptors and ligands expressed on antigen-presenting cells, T lymphocytes and tumour cells. The use of immune checkpoint inhibitors in bladder cancer has been expanded from the neoadjuvant setting, i.e., after radical cystectomy, to the adjuvant setting, i.e., before the operative time or chemotherapy, in order to improve the overall survival and to reduce the morbidity and mortality of both the disease and its treatment. However, some patients do not respond to checkpoint inhibitors. As result, the capability for identifying patients that are eligible for this immunotherapy represent one of the efforts of ongoing studies. The aim of this systematic review is to summarize the most recent evidence regarding the use of immune checkpoint inhibitors, in a neoadjuvant and adjuvant setting, in the treatment of muscle-invasive bladder cancer.

Efficacy and safety of erdafitinib in patients with locally advanced or metastatic urothelial carcinoma: long-term follow-up of a phase 2 study

BACKGROUND

Erdafitinib, a pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, was shown to be clinically active and tolerable in patients with advanced urothelial carcinoma and prespecified FGFR alterations in the primary analysis of the BLC2001 study at median 11 months of follow-up. We aimed to assess the long-term efficacy and safety of the selected regimen of erdafitinib determined in the initial part of the study.

METHODS

The open-label, non-comparator, phase 2, BLC2001 study was done at 126 medical centres in 14 countries across Asia, Europe, and North America. Eligible patients were aged 18 years or older with locally advanced and unresectable or metastatic urothelial carcinoma, at least one prespecified FGFR alteration, an Eastern Cooperative Oncology Group performance status of 0-2, and progressive disease after receiving at least one systemic chemotherapy or within 12 months of neoadjuvant or adjuvant chemotherapy or were ineligible for cisplatin. The selected regimen determined in the initial part of the study was continuous once daily 8 mg/day oral erdafitinib in 28-day cycles, with provision for pharmacodynamically guided uptitration to 9 mg/day (8 mg/day UpT). The primary endpoint was investigator-assessed confirmed objective response rate according to Response Evaluation Criteria In Solid Tumors version 1.1. Efficacy and safety were analysed in all treated patients who received at least one dose of erdafitinib. This is the final analysis of this study. This study is registered with ClinicalTrials.gov, NCT02365597.

FINDINGS

Between May 25, 2015, and Aug 9, 2018, 2328 patients were screened, of whom 212 were enrolled and 101 were treated with the selected erdafitinib 8 mg/day UpT regimen. The data cutoff date for this analysis was Aug 9, 2019. Median efficacy follow-up was 24·0 months (IQR 22·7-26·6). The investigator-assessed objective response rate for patients treated with the selected erdafitinib regimen was 40 (40%; 95% CI 30-49) of 101 patients. The safety profile remained similar to that in the primary analysis, with no new safety signals reported with longer follow-up. Grade 3-4 treatment-emergent adverse events of any causality occurred in 72 (71%) of 101 patients. The most common grade 3-4 treatment-emergent adverse events of any cause were stomatitis (in 14 [14%] of 101 patients) and hyponatraemia (in 11 [11%]). There were no treatment-related deaths.

INTERPRETATION

With longer follow-up, treatment with the selected regimen of erdafitinib showed consistent activity and a manageable safety profile in patients with locally advanced or metastatic urothelial carcinoma and prespecified FGFR alterations.

FUNDING

Janssen Research & Development.

Development of a multiplex immuno-oncology biomarker and digital pathology workflow for assessment of urothelial carcinoma

BACKGROUND

Immune checkpoint inhibitors (ICI) therapies have demonstrated significant benefit in the treatment of many tumors including high grade urothelial cancer (HGUC) of the bladder. However, variability in patients' clinical responses highlights the need for biomarkers to aid patient stratification. ICI relies on an intact host immune response. In this context, we hypothesize that key players in the antitumor immune response such as markers of activated cytotoxic T lymphocytes (CD8, granzyme-B) and immune suppression (FOXP3) may help to identify patients who will derive the greatest therapeutic benefit from ICI. A major obstacle for deployment of such a strategy is the limited quantities of tumor-derived biopsy material. Therefore, in this technical study, we develop a multiplex biomarker with digital workflow. We explored the (1) concordance of conventional single stain results using digital image analysis, and (2) agreement between digital scoring versus manual analysis.

METHODS

(1) For concordance study of single and multiplex stains, triplicate core tissue microarrays of 207 muscle invasive, HGUC of bladder had sequential 4-micron sections cut and stained with CD8, FOXP3 and granzyme-B. An inhouse developed tri-chromogen multiplex immunohistochemistry (m-IHC) assay consisting of CD8 (green), granzyme B (brown), and FOXP3 (red) was used to stain the next sequential tissue section. (2) Agreement between manual and digital analysis was performed on 19 whole slide sections of HGUC cystectomy specimens. All slides were scanned using Aperio ScanScope AT Digital Scanner at 40X. Quantitative digital image analysis was performed using QuPath version 0.2.3 open-source software. Scores from triplicate cores were averaged for each HGUC specimen for each marker. Intraclass correlation coefficients were used to compare percent positive cells between the single- and multi-plex assays. Lin's concordance correlation coefficients were used for manual versus digital analysis.

RESULTS AND CONCLUSIONS

m-IHC offers significant advantages in characterizing the host immune microenvironment particularly in limited biopsy tissue material. Utilizing a digital image workflow resulted in significant concordance between m-IHC and individual single stains (p < 0.001 for all assessments). Moderate to good agreements were achieved between manual and digital scoring. Our technical work demonstrated potential uses of multiplex marker in assessing the host immune status and could be used in conjunction with PD-L1 as a predictor of response to ICI therapy.

Expression of Semaphorin 3A in Malignant and Normal Bladder Tissue: Immunohistochemistry Staining and Morphometric Evaluation

Simple Summary

Semaphorin 3A (Sema3A) was shown to play a significant role in different neoplasms. In a previous study by our team, we showed that Sema3A is overexpressed in patients with urothelial carcinoma (UC). In this study, we analyzed 43 specimens from patients with the entire spectrum of UC and compared them with samples from 14 normal urothelium using immunostaining and computerized morphometry. The results showed that patients with UC had intense Sema3A staining in the apical layer of the mucosa compared to patients without UC. Moreover, patients with higher grade UC showed intense Sema3A staining across all mucosal layers.

Abstract

Introduction: Our previous studies showed elevated levels of Semaphorin3a (Sema3A) in the urine of patients with urothelial cancer compared to healthy patients. The aim of this study was to analyze the extent of Sema3A expression in normal and malignant urothelial tissue using immune-staining microscopic and morphometric analysis. Materials and Methods: Fifty-seven paraffin-embedded bladder samples were retrieved from our pathology archive and analyzed: 14 samples of normal urothelium, 21 samples containing low-grade urothelial carcinoma, 13 samples of patients with high-grade urothelial carcinoma, 7 samples containing muscle invasive urothelial carcinoma, and 2 samples with pure urothelial carcinoma in situ. All samples were immunostained with anti Sema3A antibodies. The area of tissue stained with Sema3A and its intensity were analyzed using computerized morphometry and compared between the samples’ groups. Results: In normal bladder tissue, very light Sema3A staining was demonstrated on the mucosal basal layer and completely disappeared on the apical layer. In low-grade tumor samples, cells in the basal layer of the mucosa were also lightly stained with Sema3A, but Seama3A expression intensified upon moving apically, reaching its highest level on apical cells exfoliating to the urine. In high grade urothelial tumors, Seama3A staining was intense in the entire thickness of the mucosa. In samples containing carcinoma in situ, staining intensity was high and homogenous in all the neoplastic cells. Conclusions: Sema3A may be serve as a potential non-invasive marker of urothelial cancer.

PIVOT-10: Phase II study of bempegaldesleukin plus nivolumab in cisplatin-ineligible advanced urothelial cancer

The choice of first-line therapy for patients with metastatic urothelial cancer (mUC) is based on cisplatin-eligibility and programmed death-ligand 1 (PD-L1) status. For patients with mUC who are ineligible for cisplatin and with low PD-L1 expression, chemotherapy-based regimens are the only approved first-line option. In a Phase I/II trial of the chemotherapy-free regimen, bempegaldesleukin (BEMPEG; NKTR-214) plus nivolumab, patients with locally advanced or mUC experienced tumor responses regardless of baseline PD-L1 expression (objective response rates: 50 and 45% in patients with PD-L1-positive and -negative tumors, respectively). The Phase II PIVOT-10 study (NCT03785925), evaluates efficacy and safety of first-line BEMPEG plus nivolumab in cisplatin-ineligible patients with locally advanced or mUC. Most patients will have low PD-L1 expression. Primary end point: objective response rates (including complete response).

Current Strategies and Novel Therapeutic Approaches for Metastatic Urothelial Carcinoma

Urothelial carcinoma (UC) is a frequent cause of cancer-related deaths worldwide. Metastatic UC has been historically associated with poor prognosis, with a median overall survival of approximately 15 months and a 5-year survival rate of 18%. Although platinum-based chemotherapy remains the mainstay of medical treatment for patients with metastatic UC, chemotherapy clinical trials produced modest benefit with short-lived, disappointing responses. In recent years, the better understanding of the role of immune system in cancer control has led to the development and approval of several immunotherapeutic approaches in UC therapy, where immune checkpoint inhibitors have been revolutionizing the treatment of metastatic UC. Because of a better tumor molecular profiling, FGFR inhibitors, PARP inhibitors, anti-HER2 agents, and antibody drug conjugates targeting Nectin-4 are also emerging as new therapeutic options. Moreover, a wide number of trials is ongoing with the aim to evaluate several other alterations and pathways as new potential targets in metastatic UC. In this review, we will discuss the recent advances and highlight future directions of the medical treatment of UC, with a particular focus on recently published data and ongoing active and recruiting trials.

Treating Japanese Patients With Pembrolizumab for Platinum-Refractory Advanced Urothelial Carcinoma in Real-World Clinical Practice

Background

Since December 2017, pembrolizumab has been approved in Japan as a second-line treatment for radical unresectable urothelial carcinoma (UC) that has become exacerbated after chemotherapy by the international randomized phase 3 trial, KEYNOTE-045. The aim of this study was to evaluate the oncological efficacy and safety of pembrolizumab after failure of platinum-based chemotherapy in Japanese patients with advanced UC in real-world clinical practice.

Methods

A total of 34 patients who received pembrolizumab after the failure of platinum-based chemotherapy for advanced urothelial carcinoma at four institutions between January 2018 and August 2019 were retrospectively evaluated. In all patients, UC was histopathologically diagnosed, and disease progression after platinum-based chemotherapy was radiologically confirmed.

Results

The median follow-up period was 7.7 months. The objective response rate, median progression-free survival, and median overall survival were 20.6%, 3.3 months, and 11.7 months, respectively. Regarding the toxicities associated with pembrolizumab, adverse events (AEs) of any grade occurred in 61.8%, and grade 3 AEs occurred in 23.5%; grade ≥ 4 AEs did not occur in any patients. Univariate analyses revealed that the Eastern Cooperative Oncology Group Performance Status, neutrophil/lymphocyte ratio, liver metastases, and time from previous chemotherapy were prognostic variables. Multivariate analyses revealed that liver metastases (positive: hazard ratio, 4.23; 95% confidence interval, 1.48 - 12.08; P < 0.01) and time from previous chemotherapy (≥ 3 months: hazard ratio, 5.06; 95% confidence interval, 1.43 - 17.91; P = 0.01) were independent prognostic factors.

Conclusions

In this real-world clinical study, these findings concerning the efficacy and safety of pembrolizumab for advanced UC in Japanese patients were comparable to those of the open-label, international, phase 3 trial KEYNOTE-045. Liver metastases and time from previous chemotherapy were independent prognostic factors in the present study.

Mycobacterium bovis infection of a femorofemoral bypass graft following intravesical Bacillus Calmette-Guérin (BCG) immunotherapy

Vascular bypass graft infection with Mycobacterium bovis following Bacillus Calmette–Guérin (BCG) immunotherapy for bladder cancer is an incredibly rare complication. We present the case of an 85-year-old man with a history of femorofemoral bypass who developed this complication over a year after BCG treatment. He was successfully treated with explantation of the polytetrafluoroethylene (PTFE) graft, redo bypass with vein graft, and antituberculous medical therapy.