Current Clinical Trials in Non-muscle-Invasive Bladder Cancer: Heightened Need in an Era of Chronic BCG Shortage

Efficacy and safety of tislelizumab plus bacillus-calmette guérin with or without chemotherapy as a bladder-sparing treatment for high-risk non-muscle-invasive bladder urothelial cancer: a real-world study

BACKGROUND

Despite adequate transurethral resection of the bladder tumor (TURBT) followed by intravesical bacillus-calmette guérin (BCG), high-risk non-muscle-invasive bladder cancer (HR-NMIBC) is associated with high rates of recurrence and progression. Immune checkpoint inhibitors can improve antitumor activity in bladder cancer, but relevant evidence in HR-NMIBC is limited. Thus, we evaluated the efficacy and safety of the tislelizumab-based combination regimen in HR-NMIBC.

METHODS

A retrospective study included 21 patients diagnosed with HR-NMIBC between July 2020 and September 2022. All patients underwent TURBT followed by combination regimens of tislelizumab plus BCG with or without gemcitabine/cisplatin (GC) chemotherapy. Clinical Data on demographics and characteristics, treatment information, outcomes, and safety were collected and analyzed.

RESULTS

Among the 21 patients with HR-NMIBC, the median age was 63 years (range 39-85), with the majority of patients with stage T1 (16/21, 76.19%). The median treatment of tislelizumab was 5 cycles (range 1-12) and the median number of BCG instillations was 12 times (range 2-19). Of the 21 patients, 15 (71.43%) received combination chemotherapy with GC, with a median treatment of 2 cycles (range 0-7); others did not. Overall, after the median follow-up of 25 months (range 7-31), the estimated 2-year bladder recurrence-free survival rate was 78.64% (95% confidence intervals [CIs], 50.79-91.83%), 2-year cystectomy-free survival rate was 83.00% (95% CI 53.53-94.59%), and 2-year disease-free survival rate was 73.39% (95% CI 46.14-88.36%). Sixteen stage T1 patients achieved a distant metastasis-free survival rate of 95.45% (95% CI 71.87-99.34%) at 2 years. Fourteen (66.67%) patients experienced at least one treatment related-AEs (TRAEs), with 9.52% (2/21) of grade 3-4. Grade ≥ 3 TRAEs were hypophysitis (1/21, 4.76%) and myasthenia (1/21, 4.76%). No treatment-related deaths were observed.

CONCLUSIONS

The study demonstrated promising clinical benefits and a manageable safety profile of tislelizumab-based combination regimen as a bladder-sparing treatment of HR-NMIBC.

Controversies in terminology associated with management of BCG-unresponsive NMIBC in Asia-Pacific

OBJECTIVES

Examine the understanding of terminologies and management patterns of bacillus Calmette-Guérin (BCG)-unresponsive nonmuscle invasive bladder cancer (NMIBC) in six territories in Asia-Pacific.

METHODS

This study involved two phases: (1) a survey with 32 urologists and 7 medical oncologists (MOs) and (2) a factorial experiment and in-depth interviews with 23 urologists and 2 MOs. All clinicians had ≥8 years' experience managing NMIBC patients in Australia, Hong Kong, Japan, South Korea, Singapore, and Taiwan. Data from Phase 1 were summarized using descriptive statistics; content and thematic analyses applied in Phase 2.

RESULTS

In phase 1, 35% of clinicians defined BCG-unresponsive as BCG-refractory, -relapse and -resistant, 6% defined it as BCG-refractory and -relapse; 22% classified BCG-failure as BCG-refractory, -relapse, -resistant, and when muscle-invasive bladder cancer is detected. If eligible and willing, 50% (interquartile range [IQR], 50%-80%) of BCG-unresponsive patients would undergo radical cystectomy (RC), and 50% (IQR 20%-50%) of RC-eligible patients would receive bladder-sparing treatment or surveillance. In phase 2, we found that 32%, 88%, and 48% of clinicians, respectively, used "BCG-unresponsive," "BCG-refractory," and "BCG-relapse" in clinical practice but with no consistent interpretation of the terms. Compared with EAU definitions, 8%-60% of clinicians appropriately classified 9 tumor types that are persistent or recurrent after adequate BCG. Fifty percent of clinicians mentioned a lack of bladder-preserving treatment that outperforms RC in quality of life as a reason to retreat BCG-unresponsive patients with BCG.

CONCLUSIONS

Our study revealed varied understanding and application of BCG-unresponsive terminologies in practice. There is a need for a uniform and simple definition of BCG-unresponsive disease in Asia-Pacific.

Heterogeneity of BCG unresponsive bladder cancer clinical trials limits patients' access to novel therapeutics

INTRODUCTION

Effective therapies for patients with nonmuscle invasive bladder cancer that recurs or progresses after Bacille Calmette-Guérin (BCG) are lacking. This unmet need is the focus of many drug development efforts, reflected in many completed/ongoing/planned clinical trials for patients with BCG unresponsive bladder cancer. Though BCG unresponsive criteria are well defined, enrollment criteria are variable such that, even at centers with several open trials in this space, a given patient with BCG unresponsive bladder cancer might not qualify for any. To understand the scope of this dilemma, we systematically analyzed enrollment criteria for all BCG unresponsive protocols registered on ClinicalTrials.gov to quantify heterogeneity in enrollment criteria and to determine what proportion of trials were inclusive to patients meeting U.S. Food and Drug Administration (FDA) BCG unresponsive criteria.

METHODS

The ClinicalTrials.gov search tool was queried for relevant trials using the terms "bladder cancer" "nonmuscle invasive bladder cancer" and "BCG". Previously published review articles were cross-referenced to ensure that search results were comprehensive. Inclusion and exclusion criteria for the resulting 31 protocols pertaining to distinct categories such as performance status, laboratory parameters, co-morbidities, active medications, and prior therapies were recorded. Based on enrollment criteria, the trial was assessed as fully inclusive or not to patients considered to be BCG unresponsive by the 2018 FDA criteria.

RESULTS

Of 31 trials, 15 (48%) had inclusion/exclusion criteria that were fully consistent with (inclusive of patients that met) the BCG unresponsive bladder cancer definition. 18 (58%) of trials excluded patients with a history of prior pelvic radiation therapy. 14 (45%) of trials excluded patients with ECOG performance status >2 (or Karnofsky Performance Status equivalent). The most common disease specific exclusion for patients with BCG unresponsive bladder cancer was a requirement for stage Tis (carcinoma in situ, CIS), which pertained to 7 (23%) of trials.

CONCLUSIONS

Enrollment criteria for patients with BCG unresponsive bladder cancer are highly variable. Over half of trials evaluated do not meet stringent criteria for this disease state based upon treatment history and cancer staging requirements. For patients who desire to enroll in clinical trials, this restricts access to novel agents. For bladder cancer treating physicians and regulatory bodies, this also hinders comparisons across agents.

Novel Delivery Mechanisms for Existing Systemic Agents and Emerging Therapies in Bladder Cancer

Systemic agents including immune checkpoint inhibitors, antibody-drug conjugates, and targeted therapies play a critical role in the management of bladder cancer. Novel localized delivery mechanisms for existing systemic agents explore solutions to improve treatment response without compromising safety. Herein, we review the contemporary innovations in modern intravesical agents, hyperthermic drug delivery, reverse-thermal gels, nanocarriers, gene therapy, and subcutaneous therapies.

Can we offer additional BCG therapy for three-month BCG refractory high grade/T1, Tis bladder cancer patients?

Background

We lack tools to predict treatment and survival outcomes in patients receiving additional BCG therapy as a bladder-preserving therapy in high grade/T1, Tis NMIBC patients who showed persistent/recurrent tumors at three-month follow-up.

Objectives

To assess the predictors of additional BCG response in patients who experienced persistent/recurrent tumors at three-month follow-up after BCG induction.

Patients and methods

We retrospectively analyzed database for NMIBC. Between 2000 and 2019, 231 patients with high-grade T1/Tis NMIBC showed persistent/recurrent tumors at 3-month after BCG-induction, refused or were unfit to radical cystectomy (RC) and were offered additional intravesical BCG as bladder-preserving treatment. Predictors of the outcome after additional BCG were studied using univariate and multivariate logistic regression analysis. Kaplan Meier curve was utilized to estimate the recurrence-free survival (RFS) and progression-free survival (PFS). COX regression analysis was performed to identify independent predictors or RFS and PFS.

Results

During a median (range) of 148 (24-224) months, poor response to additional BCG (tumor recurrence and/or progression) was noted in 112 (48.5%) patients. On multivariate logistic regression analysis, 3-month tumor features (persistent T stage, persistent grade and persistent/new CIS) significantly predicted poor response to additional BCG (OR: 3.4, 95%CI: 1.3-10.8, p = 0.021, OR: 2.1, 95%CI: 1.1-4.1, p = 0.02 and OR: 16.6, 95%CI: 4.5-109, p=<0.001, respectively). The mean RFS was 26 (9-152) months with identified 3-month tumor features (persistent T stage and persistent/new CIS) as independent predictors of RFS (HR = 11.5, 95%CI = 2.7-48.3, p = 0.001 and HR = 2.5, 95%CI = 1.5-4.1, p=<0.001, respectively) on multivariate COX regression analysis. In addition, 3-month tumor features (persistent/new CIS, non-papillary shape and bladder neck involvement) were identified to significantly predict PFS (HR = 6.2, 95%CI = 3.4-11.5, p=<0.001 and HR = 2.3, 95%CI = 1.3-4.3 p = 0.001 and HR = 2.1, 95%CI = 1.2-3.8, p=<0.005, respectively).

Conclusions

Three-month tumor features could be utilized as a tool to predict treatment outcomes and survival benefits when additional intravesical BCG is utilized as a bladder-preserving treatment in patients with recurrent/persistent tumors at three-month follow-up.

Replacement Instead of Discontinuation of Bacillus Calmette-Guérin Instillation in Non-Muscle-Invasive Bladder Cancer

BACKGROUND

To evaluate the efficacy of intravesical chemotherapy replacement in patients with intermediate- and high-risk non-muscle-invasive bladder cancer (NMIBC), who underwent bacillus Calmette-Guérin (BCG) instillation but discontinued due to global shortages or toxicity of BCG.

METHODS

This retrospective study included patients with intermediate- and high-risk NMIBC who received BCG intravesical instillation. Those who discontinued the treatment were divided into the pure BCG group and chemotherapy replacement group. Comparisons between these groups were performed. The primary endpoint was bladder recurrence-free survival (RFS).

RESULTS

A total of 480 patients were included. Baseline characteristics were similar between groups, but the total instillation times were higher in the chemotherapy replacement group than in the pure BCG group (n = 14.9 vs. 10.5). The chemotherapy replacement group had a better three-year RFS (p = 0.022). On multivariate analysis, the pure BCG group had significantly increased all-time and 3-year recurrences (hazard ratio 2.015 and 2.148) compared to the chemotherapy replacement group.

CONCLUSIONS

Chemotherapy replacement has a better three-year RFS than no instillation in patients with intermediate- and high-risk NMIBC who received BCG instillation but facing treatment stoppage.

BCG shortage for intravesical instillation is associated with early tumoral recurrence in patients with high-risk non-muscle invasive bladder tumours

INTRODUCTION

During 2019 there was a worldwide shortage of BCG strains for intravesical instillation, limiting the availability of full dose schemes for maintenance courses. The main objective was to analyze the impact on tumoral relapse secondary to BCG shortage in our center. Secondary outcomes included recurrence and progression-free survival rates and tumoral relapse specific characteristics.

METHODS

Retrospective cohort study including 158 subjects (64 treated during 2019 and 94 during 2017) with high-risk non-muscle invasive bladder cancer and treated with a combination of Transurethral bladder resection (TURB) followed by adjuvant intravesical instillation with BCG in a tertiary hospital in Spain. Basal characteristics of both groups were analyzed. Times to event of interest (relapse; including recurrence and/or progression) were estimated with Kaplan-Meier survival analysis. Disease-free survival rates were analyzed using a multivariable Cox regression model of proportional hazards.

RESULTS

Median follow-up in the 2019 sample was 24 months and 50 months in the 2017 group with a median number of instillations of 8 and 12 respectively. Median time to relapse of 285 days (145-448) during 2019 and 382 days (215-567) in 2017 were observed (logRank p = 0.025). Further multivariable analysis revealed a proportional hazard ratio (HR) for disease-free survival rate of 1.87 (95% CI: 1.04-3.37 p = 0.036). No statistically significant differences in tumoral relapse characteristics were observed.

CONCLUSION

BCG shortage and subsequent reduced-dose schemes used for intravesical instillation due to limited availability, increase early tumoral relapse rates. These findings are consistent with available evidence, showing the need for full-dose BCG courses.

Efficacy and adverse reactions of intra-arterial chemotherapy in patients with bladder cancer: A systematic review and meta-analysis

This meta-analysis investigated the efficacies of intra-arterial chemotherapy (IAC) plus intravesical chemotherapy (IVC) versus IVC alone in patients with non-muscle-invasive bladder cancer (NMIBC), and preoperative IAC versus preoperative intravenous chemotherapy (IV) in patients with bladder cancer. We also assessed the adverse reactions (ARs) of IAC. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for English articles published before April 2021. The qualities of cohort studies and randomized controlled trials were analyzed using the Newcastle-Ottawa Scale and Cochrane risk-of-bias tool, respectively. Effect outcomes were computed by random-effects and fixed-effects models. Statistical analyses were conducted using Stata 16.0 and RevMan v5.3.0. A total of seven articles were included. The analysis revealed that IAC plus IVC significantly prolonged recurrence-free survival (RFS) (hazard ratio [HR] = 0.55, 95% confidence interval [CI] = 0.40-0.76, I² = 0%) and progression-free survival (PFS) (HR = 0.59, 95% CI = 0.37-0.97, I² = 0%) compared with IVC alone in NMIBC patients after transurethral resection of bladder tumor (TURBT), but had no effect on overall survival (OS), tumor recurrence interval, or tumor-specific death rate. Preoperative IAC had no significant OS benefit compared with preoperative IV in bladder cancer patients. Regarding ARs, patients treated with IAC were significantly more likely to develop grade 1-2 ARs, including nausea/vomiting (odds ratio [OR] = 26.38, 95% CI = 1.88-370.79, I² = 78%), neutropenia (OR = 10.15, 95% CI = 3.01-34.24, I² = 0%), hypoleukemia (OR = 5.49, 95% CI = 1.38-21.82, I² = 26%), and increased alanine aminotransferase (OR = 12.28, 95% CI = 2.24-67.43, I² = 0%), but there was no significant difference between grade 1-2 ARs and grade 3-4 ARs in terms of increased creatinine in patients treated with IAC. Therefore, administration of IAC plus IVC after TURBT improved RFS and PFS compared with IAC alone in patients with NMIBC. IAC was associated with mild ARs and was well tolerated by most patients.

Predicting Recurrence of Non-Muscle-Invasive Bladder Cancer: Current Techniques and Future Trends

Bladder cancer (BC) is the 10th most common cancer globally and has a high mortality rate if not detected early and treated promptly. Non-muscle-invasive BC (NMIBC) is a subclassification of BC associated with high rates of recurrence and progression. Current tools for predicting recurrence and progression on NMIBC use scoring systems based on clinical and histopathological markers. These exclude other potentially useful biomarkers which could provide a more accurate personalized risk assessment. Future trends are likely to use artificial intelligence (AI) to enhance the prediction of recurrence in patients with NMIBC and decrease the use of standard clinical protocols such as cystoscopy and cytology. Here, we provide a comprehensive survey of the most recent studies from the last decade (N = 70 studies), focused on the prediction of patient outcomes in NMIBC, particularly recurrence, using biomarkers such as radiomics, histopathology, clinical, and genomics. The value of individual and combined biomarkers is discussed in detail with the goal of identifying future trends that will lead to the personalized management of NMIBC.

A urinary drug-disposing approach as an alternative to intravesical chemotherapy for treating non-muscle invasive bladder cancer

The standard treatment of non-muscle invasive bladder cancer (NMIBC) is transurethral resection of the tumors, followed by intravesical therapy (IT), which comprises a direct instillation of a solution of Bacillus Calmette-Guérin vaccine or chemotherapy into the bladder. However, the recurrence rate in this disease remains unacceptably high. IT is a local treatment that fails to reach tumors developed in the upper urinary tract (ureter and renal pelvis). The catheterization procedure required for IT is invasive, painful, and poses an increased infection risk resulting in poor patient quality of life and compliance. There is an unmet need for a potent, comprehensive, and non-invasive option. Without chemical modifications, peptides are rapidly removed by renal clearance. This "shortcoming" can be advantageous when used as a drug carrier for directing therapy to NMIBC. Here we develop a urinary drug-disposing (UDD) approach to improve NMIBC treatment. A 12-amino acid bio-inert peptide (Bdd) that can be exclusively eliminated via renal filtration was generated for delivering the microtubule inhibitor DM1 to NMIBC with minimal non-specific accumulation in other organs. The UDD approach prolonged survival of mice bearing human bladder tumors. Unlike IT, the treatment was given non-invasively (intravenously). Furthermore, it was more effective at suppressing tumor growth than clinically used IT (mitomycin) and safer than free DM1. The application of this urinary drug-disposing approach to treat kidney tumors and deliver other drugs such as doxorubicin was also demonstrated. Overall, the rapid renal clearance of peptides can be exploited to direct cancer therapies to the urinary system.

Intravesical sequential gemcitabine and docetaxel versus bacillus calmette-guerin (BCG) plus interferon in patients with recurrent non-muscle invasive bladder cancer following a single induction course of BCG

INTRODUCTION

Repeat BCG induction remains an option for select non-muscle invasive bladder cancer (NMIBC) patients who fail initial therapy. Alternative salvage intravesical regimens such as Gemcitabine and Docetaxel (Gem/Doce) have been investigated. We aimed to compare the efficacy BCG plus interferon a-2b (BCG/IFN) and Gem/Doce in patients with recurrent NMIBC after a single prior BCG course.

METHODS

The National Phase II BCG/IFN trial database and multi-institutional Gem/Doce database were queried for patients with recurrent NMIBC after one prior BCG induction course, excluding those with BCG unresponsive disease. Stabilized inverse probability treatment weighted survival curves were estimated using the Kaplan-Meier method and compared. Propensity scores were derived from a logistic regression model. The primary outcome was recurrence free survival (RFS); secondary outcomes were high-grade (HG) RFS and risk factors for treatment failure.

RESULTS

We identified 197 BCG/IFN and 93 Gem/Doce patients who met study criteria. Patients receiving Gem/Doce were older and more likely to have HG disease, CIS, and persistent disease following induction BCG (all P < 0.01). After propensity score-based weighting, the adjusted 1- and 2-year RFS was 61% and 53% after BCG/IFN versus 68% and 46% after Gem/Doce (P = 0.95). Adjusted 1- and 2-year HG-RFS was 60% and 51% after BCG/IFN versus 63% and 42% after Gem/Doce (P = 0.68). Multivariable Cox regression revealed that Gem/Doce treatment was not associated with an increased risk of failure (HR = 0.97, P = 0.89) as compared to BCG/IFN.

CONCLUSION

Patients with recurrent NMIBC after a single induction BCG failure and not deemed BCG unresponsive had similar oncologic outcomes with Gem/Doce and BCG/IFN in a post-hoc analysis. Additional prospective studies are needed.

Efficacy of Intra-Arterial Plus Intravesical Chemotherapy for High-Risk Non-Muscle-Invasive Bladder Cancer: A Pooled Analysis

Background: The treatment for high-risk non-muscle-invasive bladder cancer (NMIBC) remains highly debated for its high recurrence and progression risk. This work aimed to verify the efficacy and toxicity of intra-arterial chemotherapy (IAC) plus intravesical chemotherapy (IVC) in high-risk NMIBC.

Methods: A comprehensive online literature search was conducted in three databases to select researches related to IAC + IVC for high-risk NMIBC. All data were analyzed using the Review Manager software version 5.3. And we used the Cochrane Risk of Bias tool to assessed the quality of these enrolled researches.

Results: Seven eligible original publications were enrolled in our studies with a total of 1,247 patients. Compared with the intravesical instillation, IAC + IVC therapy showed a better therapeutic effect. The total odds ratio for tumor recurrence rate, tumor progression rate, survival rate, and tumor-specific death rate was calculated as 0.51 (95% CI: 0.36–0.72; p < 0.05), 0.51 (95% CI: 0.36–0.72; p < 0.05), 1.75 (95% CI: 1.09–2.81; p < 0.05), and 0.48 (95% CI: 0.28–0.84; p < 0.05), respectively. In patients who received IAC, most of the adverse events (AEs)in the treatment were Grade I and II.

Conclusion: IAC + IVC regimen for high-risk NMIBC could effectively reduce recurrence and progression and provide a better prognosis than intravesical instillation. The adverse events of IAC were mild and acceptable.

Predictive value of immunological markers after bacille Calmette-Guérin induction in bladder cancer

OBJECTIVES

To investigate the predictive value of different immunological markers on treatment outcomes after bacille Calmette-Guérin (BCG) induction in high-risk non-muscle-invasive bladder cancer (NMIBC).

PATIENTS AND METHODS

Patients who underwent transurethral resection of bladder tumour for NMIBC were assessed for study eligibility. Urine and blood samples were taken from patients at baseline (immediately before first dose of induction) and after induction (4 h after last [sixth] dose). Urine samples were evaluated for interleukin (IL)-2 and IL-10 by solid-phase enzyme-linked immunosorbent assay. Blood samples were evaluated for tumour necrosis factor α (TNF-α), cytotoxic T-lymphocyte antigen 4 (CTLA-4) and transcription factors (TFs) (GATA-binding protein 3 [GATA3], T-box expressed in T cells [T-bet], and forkhead box protein 3 [FoxP3]) using quantitative reverse transcriptase-polymerase chain reaction analysis. Change pattern and fold change of each evaluable marker was assessed in relation to different treatment outcomes (initial complete response [ICR]/recurrence/progression).

RESULTS

Between July 2013 and May 2019, 204 patients were included. Among evaluable markers, urinary IL-2 and serum TNF-α increased in all patients, serum CTLA-4 and FoxP3⁺ showed a predominant decreased pattern in 188 (92.2%) and 192 (94.1%) patients, respectively. An ICR was achieved in 186 (91.2%) patients. Serum TNF-α fold change and urinary IL-10 change pattern were significantly associated with an ICR (P = 0.001 and P = 0.03, respectively). At a median (range) follow-up of 37 (20-88) months, 104 (56%) patients developed recurrence. Urinary IL-10, serum CTLA-4, T-bet⁺ , FoxP3⁺ change patterns and GATA3⁺ /T-bet⁺ ratio were significantly associated with tumour recurrence (P = 0.001, P = 0.001, P = 0.02, P = 0.009 and P = 0.001, respectively). Tumour progression occurred in 34 (18.3%) patients. Urinary IL-10, serum CTLA-4, serum T-bet⁺ change patterns and GATA3⁺ /T-bet⁺ ratio were independent predictors of tumour progression (P = 0.001, P = 0.001, P = 0.02 and P = 0.001, respectively).

CONCLUSIONS

Urinary IL-10 and serum TNF-α can significantly predict ICR. Moreover, change pattern of urinary IL-10, serum CTLA-4, TFs (GATA3, T-bet and FoxP3) and GATA3⁺ /T-bet⁺ ratio after BCG induction can independently predict further BCG response. These markers could be implemented in clinical practice when management options are discussed or in systems with severe BCG shortage.

Bacillus Calmette-Guérin-unresponsive non-muscle invasive bladder cancer outcomes in patients without radical cystectomy

BACKGROUND

Bacillus Calmette-Guérin (BCG)-unresponsive non-muscle invasive bladder cancer (NMIBC) is a newly defined subtype that is unlikely to benefit from BCG rechallenge. Radical cystectomy is currently recommended for BCG-unresponsive NMIBC; however, a certain proportion of these patients can be managed with treatments other than that. Herein, we conducted a multicenter retrospective study to analyze the clinical outcomes of BCG-unresponsive NMIBC patients who did not receive radical cystectomy.

METHODS

Of the 141 BCG-unresponsive NMIBC patients, 94 (66.7%) received treatment except radical cystectomy. Survival outcomes were calculated from the date of diagnosis using the Kaplan-Meier method and compared using the log-rank test. Prognostic factors were identified using the multivariate Cox regression model. This group was further classified into three groups according to the number of risk factors, and survival outcomes were compared.

RESULTS

Multivariate analyses identified low estimated glomerular filtration rate (< 45 ml/min/1.73 m²) and large tumor size (≥ 30 mm) before BCG induction as independent poor prognostic factors for progression-free survival and overall survival, while the latter was also an independent factor for cancer-specific survival. The presence of variant histology was an independent poor prognostic factor for overall survival. The high-risk non-cystectomy group showed a significantly poor prognosis for progression-free survival (hazard ratio: 7.61, 95% confidence interval: 2.11-27.5), cancer-specific survival (10.4, 0.54-70.02), and overall survival (8.28, 1.82-37.7).

CONCLUSIONS

Our findings suggest that patients with renal impairment and large tumors should undergo radical cystectomy if the complications and intentions of the patients allow so.

Approaches to Non-Muscle-Invasive Bladder Cancer

PURPOSE OF REVIEW

Non-muscle-invasive bladder cancer (NMIBC) is a heterogenous malignancy with high recurrence and progression rates, which necessitate uniform recommendations for diagnosis and management. Herein, we review the literature, with an emphasis on guidelines and contemporary diagnostic techniques and interventions.

RECENT FINDINGS

Guidelines around the world have adopted a schema which risk-stratify cases at diagnosis, to offer evidence-based treatment and surveillance recommendations. Enhanced endoscopic technologies can improve detection of NMIBC and reduce recurrence. The present Bacillus Calmette-Guerin (BCG) shortage in the USA has led to new strategies to prioritize the most high-risk cases. The entity of BCG-unresponsive high-risk NMIBC remains a challenge to manage, with multiple novel treatments under investigation; fortunately, new therapies have been approved, such as immune checkpoint inhibitors, and others are showing tremendous promise. The standardization of NMIBC management, with evolving detection techniques and therapeutics, offers great potential to improve patient outcomes and survivorship.

Comparison of Side Effects and Tolerability Between Intravesical Bacillus Calmette-Guerin, Reduced-Dose BCG and Gemcitabine for Non-Muscle Invasive Bladder Cancer

OBJECTIVES

To compare patient-reported side effects and tolerability of full-dose Bacillus Calmette-Guérin (BCG), reduced-dose BCG, and gemcitabine one week after administration.

METHODS

All patients from July 2019 to November 2020 receiving intravesical therapy (IVT) for non-muscle invasive bladder cancer (NMIBC) at our institution were surveyed before repeat instillation. Survey questions recorded IVT retention times and the duration and severity of the following side effects: bladder symptoms, fatigue, body aches, hematuria, fever, chills, and other. All responses were collected and quantified in a de-identified, password-protected database. Statistical analysis was performed using SAS JMP 13.

RESULTS

Of 592 surveys completed, symptoms of any kind were reported on 463 surveys (78%) with the most common symptoms including bladder symptoms (59%), fatigue (52%), body aches (26%), and hematuria (18%). Patients were able to hold full-dose BCG, reduced-dose BCG, and gemcitabine for the protocol-specified duration 87%, 95%, and 71% of the time (P <0.05). The prevalence, severity, and duration of body aches were highest with gemcitabine (P <0.05) while the prevalence and duration of hematuria were higher with BCG (P <0.05). Reduced-dose BCG had the lowest prevalence, severity, and duration of fatigue (P <0.05).

CONCLUSION

Significant differences in the side effects and tolerability of full-dose BCG, reduced-dose BCG, and gemcitabine were demonstrated using this novel survey, and these differences are of value for informing IVT selection. Evaluation of IVTs other than gemcitabine and BCG will further inform selection of therapies for NMIBC.

The current landscape of salvage therapies for patients with bacillus Calmette-Guérin unresponsive nonmuscle invasive bladder cancer

PURPOSE OF REVIEW

Although radical cystectomy represents the gold standard treatment for patients with high-risk nonmuscle invasive bladder cancer (NMIBC) whose disease does not respond to bacillus Calmette-Guérin (BCG), many patients are unable or unwilling to undergo surgery. The need remains for effective bladder-preserving therapies. This review aims to describe existing treatments, contemporary research in this field and ongoing trials of salvage therapies for patients with BCG-unresponsive NMIBC.

RECENT FINDINGS

Intravesical chemotherapy has been utilized frequently in this setting. Emerging data on combination regimens such as intravesical gemcitabine and docetaxel and intravesical cabazitaxel, gemcitabine and cisplatin are promising; nevertheless, larger, prospective trials are needed. Meanwhile, the intravenous checkpoint inhibitor pembrolizumab was recently FDA-approved for patients BCG-unresponsive NMIBC. Encouraging clinical trial results for intravesical nadofaragene firadenovec, oportuzumab monatox and ALT-803 + BCG have been released, while data from trials of other treatment strategies, including novel chemotherapy and drug delivery, augmented BCG immunotherapy, adenoviral and gene therapy, targeted therapy, and combination systemic immunotherapy with intravesical agents, are eagerly awaited.

SUMMARY

Several novel salvage therapies offer promise for patients with BCG-unresponsive NMIBC. Patient selection, efficacy, safety, cost and ease of administration must be carefully considered to determine the optimal treatment approach.

NKTR-255, a novel polymer-conjugated rhIL-15 with potent antitumor efficacy

BACKGROUND

NKTR-255 is a novel polyethylene glycol-conjugate of recombinant human interleukin-15 (rhIL-15), which was designed to retain all known receptor binding interactions of the IL-15 molecule. We explored the biologic and pharmacologic differences between endogenous IL-15 receptor α (IL-15Rα)-dependent (NKTR-255 and rhIL-15) and IL-15Rα-independent (precomplexed rhIL-15/IL-15Rα) cytokines.

METHODS

In vitro pharmacological properties of rhIL-15, NKTR-255 and precomplex cytokines (rhIL-15/IL-15Rα and rhIL-15 N72D/IL-15Rα Fc) were investigated in receptor binding, signaling and cell function. In vivo pharmacokinetic (PK) and pharmacodynamic profile of the cytokines were evaluated in normal mice. Finally, immunomodulatory effect and antitumor activity were assessed in a Daudi lymphoma model.

RESULTS

NKTR-255 and rhIL-15 exhibited similar in vitro properties in receptor affinity, signaling and leukocyte degranulation, which collectively differed from precomplexed cytokines. Notably, NKTR-255 and rhIL-15 stimulated greater granzyme B secretion in human peripheral blood mononuclear cells versus precomplexed cytokines. In vivo, NKTR-255 exhibited a PK profile with reduced clearance and a longer half-life relative to rhIL-15 and demonstrated prolonged IL-15R engagement in lymphocytes compared with only transient engagement observed for rhIL-15 and precomplexed rhIL-15 N72D/IL-15Rα Fc. As a consequent, NKTR-255 provided a durable and sustained proliferation and activation of natural killer (NK) and CD8+ T cells. Importantly, NKTR-255 is more effective than the precomplexed cytokine at inducing functionally competent, cytotoxic NK cells in the tumor microenvironment and the properties of NKTR-255 translated into superior antitumor activity in a B-cell lymphoma model versus the precomplexed cytokine.

CONCLUSIONS

Our results show that the novel immunotherapeutic, NKTR-255, retains the full spectrum of IL-15 biology, but with improved PK properties, over rhIL-15. These findings support the ongoing phase 1 first-in-human trial (NCT04136756) of NKTR-255 in participants with relapsed or refractory hematologic malignancies, potentially advancing rhIL-15-based immunotherapies for the treatment of cancer.

[CpG-ODN instillation boosts ICAM-1 expression in an orthotopic murine UCC model: immunohistochemical evaluation of the local response to immunostimulatory DNA]

BACKGROUND

Immunostimulatory CpG oligodeoxynucleotides (CpG-ODN) have been verified as an effective antineoplastic agent for intravesical application in a murine orthotopic C57-BL6 /MB-49 urothelial cell carcinoma (UCC). To date, many details in the mode of action have remained unclear. Preceding studies pointed towards a Th1-weighted response. The aim of this work was to identify the local lymphocyte subsets in murine tumour-bearing bladders and to examine effects on the expression of Intercellular Adhesion Molecule 1 (ICAM-1) after treatment with CpG-ODN.

MATERIAL AND METHODS

Different instillation schedules were applied in an established orthotopic C57-BL6 /MB49 UCC model. After 13 days, fresh frozen sections of the harvested bladders were immunohistochemically examined for the infiltration density of lymphocytes expressing CD 3, CD4, CD8 and CD19. In a second series of the same animal model, healthy and tumour-bearing bladders were exposed to CpG-ODN or PBS and later stained for the expression of ICAM-1.

RESULTS

CpG-ODN instillation led to augmented T-cell infiltration (represented by CD3). Further T-cell subdifferentiation between T-helper cells (CD4) and cytotoxic T cells (CD 8a) did not show a perceptible variety between groups. The B-cell population (CD19) was found to decrease over the course of treatment. In the second series, treatment provoked a strong expression of ICAM-1 by infiltrating leukocytes, endothelial cells and particularly by the cancer cells themselves.

DISCUSSION

The previously observed augmented lymphocyte density was classified as T-cell infiltration. The decline of the B-cell concentration over the course of treatment suggests a Th2 suppression in favour of a Th-1 polarisation. These findings support the assumption that a cell-mediated immune response is the mode of action underlying the antineoplastic CpG-ODN capacities. The marked upregulation of ICAM-1 expression, especially on tumour cells, suggests a crucial role of this membrane protein for the initiation and maintenance of anticancer immune response.

CONCLUSION

CpG-ODN might be a prospective alternative to established instillation therapies. With a view to the current BCG shortage and the well-known toxicities, an amplification of the topic therapy armamentarium could be achievable. The now described capability of ICAM-1 induction on carcinoma cells and, by association, the reversal of escape strategies to cancer immunity may also make the agent interesting as an adjuvant for modern checkpoint inhibition.

Non-maintenance intravesical Bacillus Calmette-Guérin induction therapy with eight doses in patients with high- or highest-risk non-muscle invasive bladder cancer: a retrospective non-randomized comparative study

Background

To explore possible solutions to overcome chronic Bacillus Calmette–Guérin (BCG) shortage affecting seriously the management of non-muscle invasive bladder cancer (NMIBC) in Europe and throughout the world, we investigated whether non-maintenance eight-dose induction BCG (iBCG) was comparable to six-dose iBCG plus maintenance BCG (mBCG).

Methods

This observational study evaluated 2669 patients with high- or highest-risk NMIBC who treated with iBCG with or without mBCG during 2000–2019. The patients were classified into five groups according to treatment pattern: 874 (33%) received non-maintenance six-dose iBCG (Group A), 405 (15%) received six-dose iBCG plus mBCG (Group B), 1189 (44%) received non-maintenance seven−/eight-dose iBCG (Group C), 60 (2.2%) received seven−/eight-dose iBCG plus mBCG, and 141 (5.3%) received only ≤5-dose iBCG. Recurrence-free survival (RFS), progression-free survival, and cancer-specific survival were estimated and compared using Kaplan–Meier analysis and the log-rank test, respectively. Propensity score-based one-to-one matching was performed using a multivariable logistic regression model based on covariates to obtain balanced groups. To eliminate possible immortal bias, 6-, 12-, 18-, and 24-month conditional landmark analyses of RFS were performed.

Results

RFS comparison confirmed that mBCG yielded significant benefit following six-dose iBCG (Group B) in recurrence risk reduction compared to iBCG alone (groups A and C) before (P < 0.001 and P = 0.0016, respectively) and after propensity score matching (P = 0.001 and P = 0.0074, respectively). Propensity score-matched sequential landmark analyses revealed no significant differences between groups B and C at 12, 18, and 24 months, whereas landmark analyses at 6 and 12 months showed a benefit of mBCG following six-dose iBCG compared to non-maintenance six-dose iBCG (P = 0.0055 and P = 0.032, respectively). There were no significant differences in the risks of progression and cancer-specific death in all comparisons of the matched cohorts.

Conclusions

Although non-maintenance eight-dose iBCG was inferior to six-dose iBCG plus mBCG, the former might be an alternative remedy in the BCG shortage era. To overcome this challenge, further investigation is warranted to confirm the real clinical value of non-maintenance eight-dose iBCG.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07966-7.

PD-L2 Is Constitutively Expressed in Normal and Malignant Urothelium

The use of immune checkpoint blockade, in particular PD-1 and PD-L1 inhibitors, is now commonplace in many clinical settings including the treatment of muscle-invasive bladder cancer (MIBC). Notwithstanding, little information exists regarding the expression of the alternative PD-1 ligand, PD-L2 in urothelial bladder cancer (UBC). We therefore set out to characterise the expression of PD-L2 in comparison to PD-L1. Firstly, we assessed PD-L2 expression by immunohistochemistry and found widespread expression of PD-L2 in UBC, albeit with reduced expression in MIBC. We further investigated these findings using RNA-seq data from a cohort of 575 patients demonstrating that PDCD1LG2 (PD-L2) is widely expressed in UBC and correlated with CD274 (PD-L1). However, in contrast to our immunohistochemistry findings, expression was significantly increased in advanced disease. We have also provided detailed evidence of constitutive PD-L2 expression in normal urothelium and propose a mechanism by which PD-L2 is cleaved from the cell surface in MIBC. These data provide a comprehensive assessment of PD-L2 in UBC, showing PD-L2 is abundant in UBC and, importantly, constitutively present in normal urothelium. These data have implications for future development of immune checkpoint blockade, and also the understanding of the function of the immune system in the normal urinary bladder.

The association of salvage intravesical therapy following BCG with pathologic outcomes and survival after radical cystectomy for patients with high-grade non-muscle invasive bladder cancer: A multi-institution analysis

INTRODUCTION

While numerous current clinical trials are testing novel salvage therapies (ST) for patients with recurrent nonmuscle invasive bladder cancer (NMIBC) after bacillus Calmette-Guérin (BCG), the natural history of this disease state has been poorly defined to date. Herein, we evaluated oncologic outcomes in patients previously treated with BCG and ST who subsequently underwent radical cystectomy (RC).

METHODS

We identified 378 patients with high-grade NMIBC who received at least one complete induction course of BCG (n = 378) with (n = 62) or without (n = 316) additional ST and who then underwent RC between 2000 and 2018. Oncologic outcomes were compared using the Kaplan-Meier method and Cox proportional hazards models. Sensitivity analyses were conducted stratifying by presenting tumor stage, matched 1:3 for receipt vs. no receipt of ST.

RESULTS

Patients receiving ST were more likely to initially present with CIS (26% vs. 17%) and less likely with T1 disease (34% vs. 50%, P = 0.06) compared to patients not treated with ST. Receipt of ST was not associated with increased risk of adverse pathology (≥pT2 or pN+) at RC (31% vs. 41%, P = 0.14). Likewise, 5-year cancer-specific survival did not significantly differ between groups on univariable Kaplan-Meier analysis (73% for ST and 74% for no ST, P = 0.7). Moreover, on multivariable analysis, receipt of ST was not significantly associated the risk of death from bladder cancer (HR 1.12; 95% CI 0.60-2.09, P = 0.7). Results were unchanged on sensitivity analysis.

CONCLUSIONS

These data suggest that, in carefully selected patients, ST following BCG for high grade NMIBC does not compromise oncologic outcomes for patients who ultimately undergo RC.

Intra-arterial chemotherapy combined with intravesical chemotherapy compared with intravesical BCG immunotherapy retrospectively in high-risk non-muscle-invasive bladder cancer after transurethral resection of the bladder tumor

OBJECTIVE

To compare the efficacy and safety of intra-arterial chemotherapy (IAC) combined with intravesical chemotherapy (IVC) against intravesical BCG immunotherapy in high-risk non-muscle-invasive bladder cancer (NMIBC) after transurethral resection of the bladder tumor (TURBT).

MATERIALS AND METHODS

130 patients with high-risk NMIBC who had underwent TURBT were divided into two groups, of which IAC + IVC group received four courses of IAC (cisplatin and epirubicin) combined with IVC (epirubicin or pirarubicin) after surgery and BCG group received intravesical BCG immunotherapy. Recurrence rate and progression rate were assessed by Chi-square test, while recurrence-free survival and progression-free survival were calculated using the Kaplan-Meier method.

RESULTS

In this study, the recurrence rate was 27.9% (12/43) in IAC + IVC group and 26.4% (14/53) in BCG group, while progression rate was 9.3% (4/43) in IAC + IVC group and 9.4% (5/53) in BCG group. Both of the recurrence and progression rate did not show a significant difference. In the Kaplan-Meier plot, no difference was found with respect to recurrence-free survival and progression-free survival. Moreover, 46.5% (20/43) patients suffered from adverse events of IAC and 83.1% (49/59) patients suffered from adverse events associated with BCG, of which 6 patients discontinued treatment due to serious adverse events of BCG. Univariate analysis suggested that only recurrent tumor could be an independent risk factor related to recurrence.

CONCLUSIONS

IAC combined with IVC used in high-risk NMIBC could reduce the recurrence and progression as effective as BCG instillation with lower adverse events.

New immunotherapies for high-risk non-muscle invasive bladder cancer: Current state and future perspectives

BACKGROUND

The standard treatment for high-risk non-muscle invasive bladder tumors (NMIBT) is transurethral resection of the bladder and BCG instillations. However, responses are limited, and new therapeutic alternatives for these patients are required. The results of checkpoint inhibitors in advanced tumors have led to interest in the use of these molecules in NMIBT.

METHODS

We conducted a search on PubMed using the terms «bladder cancer» and «check point inhibitors». We have used the search engines clinicaltrials.gov and clinicaltrialsregister.eu for the search of clinical trials.

RESULTS

There are currently 5 trials in progress on BCG untreated patients. There are no results available. As for BCG non-responders, there are 15 ongoing trials, two of them with preliminary results: Keynote 057, with promising results with pembrolizumab, which has led the FDA to approve its use in January 2020, and SWOG S1605, which has shown similar results with atezolizumab. Other trials are using intravesical administration of these drugs, which is an attractive option if it is effective for cancer control.

CONCLUSIONS

Checkpoint inhibitors offer a new possibility for patients who do not respond to BCG. These will probably be used in the future for previously BCG untreated patients. Preliminary data from clinical trials show promising results. A good understanding of these molecules by urologists and the creation of multidisciplinary teams are crucial in order to offer the best therapeutic alternatives to these patients.

An evaluation of UGN-101, a sustained-release hydrogel polymer-based formulation containing mitomycin-C, for the treatment of upper urothelial carcinomas

INTRODUCTION

The treatment of low-grade upper tract urothelial carcinomas (UTUCs) after either surgery, or nephron-sparing techniques remains an unmet need in Genitourinary (GU) Oncology. UGN-101 is a novel drug in development for the treatment of UTUCs; it is composed of a sustained-release hydrogel polymer-based formulation containing the antitumor antibiotic mitomycin-C (MM-C); cold UGN-101 is liquid, but at body temperature, it becomes a gel, and thus, when administered through a ureteral catheter, it sticks to the upper tract urothelium, slowly releasing MM-C.

AREAS COVERED

Here, the authors review the preclinical rationale for the development of UGN-101, as well as presently available clinical results for the treatment of low-grade UTUCs.

EXPERT OPINION

The positive results of the recently completed OLYMPUS trial suggest the feasibility, activity (59% of complete responses, with just 6 of these complete responders on follow-up who recurred), and safety (68% of patients experiencing mild to moderate urinary adverse events) of UGN-101 instillations into the upper urinary tract. Our expectations are that UGN-101 will soon become a standard of treatment for low-grade UTUC at risk of relapse after either surgery, or nephron-sparing techniques.

New Roadmaps for Non-muscle-invasive Bladder Cancer With Unfavorable Prognosis

About 70% of bladder cancers (BCs) are diagnosed as non-muscle-invasive BCs (NMIBCs), while the remaining are muscle-invasive BCs (MIBCs). The European Association of Urology (EAU) guidelines stratify NMIBCs into low, intermediate, and high risk for treatment options. Low-risk NMIBCs undergo only the transurethral resection of the bladder (TURB), whereas for intermediate-risk and high-risk NMIBCs, the transurethral resection of the bladder (TURB) with or without Bacillus Calmette-Guérin (BCG) immune or chemotherapy is the standard treatment. A minority of NMIBCs show unfavorable prognosis. High-risk NMIBCs have a high rate of disease recurrence and/or progression to muscle-invasive tumor and BCG treatment failure. The heterogeneous nature of NMIBCs poses challenges for clinical decision-making. In 2020, the EAU made some changes to NMIBCs BCG failure definitions and treatment options, highlighting the need for reliable molecular markers for improving the predictive accuracy of currently available risk tables. Nowadays, next-generation sequencing (NGS) has revolutionized the study of cancer biology, providing diagnostic, prognostic, and therapy response biomarkers in support of precision medicine. Integration of NGS with other cutting-edge technologies might help to decipher also bladder tumor surrounding aspects such as immune system, stromal component, microbiome, and urobiome; altogether, this might impact the clinical outcomes of NMBICs especially in the BCG responsiveness. This review focuses on NMIBCs with unfavorable prognoses, providing molecular prognostic factors from tumor immune and stromal cells, and the perspective of urobiome and microbiome profiling on therapy response. We provide information on the cornerstone of immunotherapy and new promising bladder-preserving treatments and ongoing clinical trials for BCG–unresponsive NMIBCs.

Low compliance to guidelines in nonmuscle-invasive bladder carcinoma: A systematic review

PURPOSE

This systematic review assessed compliance to guidelines for the management of nonmuscle-invasive bladder carcinoma (NMIBC).

METHODS

The PUBMED, Web of Science, Cochrane Library, and Scopus databases were searched in November 2019 in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis statement.

RESULTS

Fifteen studies incorporating a collective total of 10,575 NMIBC patients were eligible for inclusion in this systematic review. We found that the rates of compliance were 53.0% with a single immediate intravesical instillation in patients with presumed low or intermediate risk, 37.1% with intravesical bacillus Calmette-Guerin or chemotherapy in those with intermediate risk, 43.4% with performance of a second transurethral resection in high-risk patients, 32.5% with administration of adjuvant intravesical bacillus Calmette-Guerin in high-risk patients, 36.1% with radical cystectomy in highest-risk patients, and 82.2% with cystoscopy for follow-up.

CONCLUSIONS

Compliance with NMIBC guidelines remains low. Better guideline education and understanding holds the key to achieving high compliance. Strategies to improve guideline compliance at the physician level are urgently required.

Bacillus Calmette-Guérin (BCG) Therapy for Bladder Cancer: An Update

Physicians treating patients affected by nonmuscle-invasive bladder cancer (NMIBC) have been in shock during the last six years since manufacturing restrictions on the production of the first-option medicine, Mycobacterium bovis Bacillus Calmette-Guérin (BCG), have resulted in worldwide shortages. This shortage of BCG has led to a rethinking of the established treatment guidelines for the rationing of the administration of BCG. Some possible schedule modifications consist of a decrease in the length of maintenance treatment, a reduction in the dose of BCG in intravesical instillations or the use of different BCG substrains. All these strategies have been considered valuable in times of BCG shortage. In addition, the lack of availability of BCG has also led to the general recognition of the need to find new treatment options for these patients so that they are not dependent on a single treatment. Few alternatives are committed to definitively replacing BCG intravesical instillations, but several options are being evaluated to improve its efficacy or to combine it with other chemotherapeutic or immunotherapeutic options that can also improve its effect. In this article, we review the current state of the treatment with BCG in terms of all of the aforementioned aspects.