How Immunotherapy Has Redefined the Treatment Paradigm of Metastatic or Locally Advanced Muscle-Invasive Urothelial Bladder Carcinoma

In the past decade, the therapeutic arsenal for metastatic bladder cancer has expanded considerably, with the development of immune checkpoint inhibitors (ICIs), antibody-drug conjugates such as enfortumab vedotin, and anti-fibroblast growth factor receptor agents. Clinical trials evaluating ICIs as neoadjuvants, adjuvants, or first- or second-line treatments have produced conflicting results. However, first-line therapeutic strategies have been redefined by the recent publication of results from two clinical trials: CheckMate-901, which demonstrated the superiority of combined treatment with nivolumab and chemotherapy in extending overall survival, and EV-302, which demonstrated that combined treatment with pembrolizumab and enfortumab vedotin reduced the risk of death by 53%. In this review, we discuss the role of ICIs, alone or in combination, in bladder cancer management in the metastatic and adjuvant settings in 2024, considering the latest published trials. The potential role of ICIs as neoadjuvants is also discussed.

Recent advances in immune checkpoint inhibitors in the treatment of urothelial carcinoma: A review

Treatment options for urothelial carcinoma were limited until the emergence of immune checkpoint inhibitors, and even now, the prognosis of metastatic disease is poor compared with the other two major genitourinary cancers, renal cell carcinoma and prostate cancer. Despite the increasing use of immune checkpoint inhibitors in the sequential treatment of urothelial carcinoma, conflicting results from similar randomized clinical trials call into question the efficacy of this treatment. In addition, physicians must be aware of the clinical characteristics of immune checkpoint inhibitors, including immune-related adverse events, pseudo- and hyperprogression. This review summarizes the conflicting results of recent clinical trials and provides insights into the role of immune checkpoint inhibitors in the treatment of urothelial carcinoma.

The CHASIT study: sequential chemo-immunotherapy in patients with locally advanced urothelial cancer - a non-randomized phase II clinical trial

BACKGROUND

Patients with locally advanced irresectable or clinically node positive urothelial cancer (UC) have a poor outcome. Currently, these patients can only be cured by receiving induction chemotherapy and, if an adequate radiological response is obtained, radical surgical resection. Long-term survival, however, strongly depends on the absence of residual tumor in the surgical resection specimen, i.e. a pathological complete response (pCR). The reported pCR rate following induction chemotherapy in locally advanced or clinically node-positive UC is 15%. The 5-year overall survival rate for patients achieving a pCR is 70-80% versus 20% for patients who have residual disease or nodal metastases. This clearly demonstrates the unmet need to improve clinical outcome of these patients. Recently, the JAVELIN Bladder 100 study demonstrated an overall survival benefit of sequential chemo-immunotherapy in patients with metastatic UC. The CHASIT study aims to translate these findings to the induction setting by assessing the efficacy and safety of sequential chemo-immunotherapy in patients with locally advanced or clinically node-positive UC. In addition, patient biomaterials are collected to investigate biological mechanisms of response and resistance to chemo-immunotherapy.

METHODS

This multicenter, prospective phase II clinical trial includes patients with stage cT4NxM0 or cTxN1-N3M0 UC of the bladder, upper urinary tract or urethra. Patients who do not experience disease progression after 3 or 4 cycles of platinum-based chemotherapy are eligible for inclusion. Included patients receive 3 cycles of anti-PD-1 immunotherapy with avelumab followed by radical surgery. Primary endpoint is the pCR rate. It is hypothesized that sequential chemo-immunotherapy results in a pCR rate of ≥ 30%. To obtain a power of 80%, 64 patients are screened and 58 patients are included in the efficacy analysis. Secondary endpoints are toxicity, postoperative surgical complications, progression-free, cancer-specific and overall survival at 24 months.

DISCUSSION

This is the first study to assess the potential benefit of sequential chemo-immunotherapy in patients with locally advanced or node positive UC. If the primary endpoint of the CHASIT study is met, i.e. a pCR rate of ≥ 30%, a randomized controlled trial is foreseen to compare this new treatment regimen to standard care.

TRIAL REGISTRATION

NCT05600127 at Clinicaltrials gov, registered on 31/10/2022.

Perioperative systemic therapy in muscle invasive bladder cancer: Current standard method, biomarkers and emerging strategies

Bladder cancer ranks as the 10th most common cancer type globally, and muscle-invasive disease accounts for approximately 25% of newly diagnosed bladder cancers. Despite definitive treatment, 50% of patients with muscle-invasive bladder cancer (MIBC) develop metastasis within 2 years, leading to death. Perioperative systemic therapy is generally recommended to control local relapse or distant metastasis after surgical resection for patients with MIBC. Cisplatin-based neoadjuvant chemotherapy followed by radical cystectomy is the current standard treatment to improve oncologic control and survival outcomes. Adjuvant chemotherapy is recommended for patients with pathological T3-4 or positive lymph nodes after radical cystectomy if no neoadjuvant chemotherapy was given. Nonetheless, perioperative systemic therapy is not applied widely because of its toxicity, and less than 25% of patients receive cisplatin-based neoadjuvant chemotherapy. Therefore, the development of predictive biomarkers for neoadjuvant chemotherapy efficacy and alternative effective regimens for cisplatin-ineligible patients are important. Furthermore, recently, novel anticancer agents such as immune checkpoint inhibitors and antibody-drug conjugates have proven survival benefits in the metastatic setting, thereby expanding their therapeutic applications to the perioperative setting for non-metastatic MIBC. Herein, we discuss the current status and future perspectives of perioperative systemic strategies for MIBC.

Current Status of Perioperative Therapy in Muscle-Invasive Bladder Cancer and Future Directions

PURPOSE OF REVIEW

Cisplatin-based combination chemotherapy has been a standard of care in the perioperative management of muscle-invasive bladder cancer for years, but several novel therapies are under active investigation. This review aims to provide an update on recent relevant literature and a forward look at the future landscape of adjuvant and neoadjuvant therapy in muscle-invasive bladder cancer patients who opt for radical cystectomy.

RECENT FINDINGS

The recent approval of nivolumab as adjuvant therapy established a new treatment option for high-risk patients with muscle-invasive bladder cancer after radical cystectomy. Several phase II studies of chemo-immunotherapy combinations and immunotherapy alone have reported pathological complete responses in the 26-46% range, including studies in cisplatin-ineligible patients. Randomized studies of perioperative chemo-immunotherapy, immunotherapy alone, and enfortumab vedotin are ongoing. Muscle-invasive bladder cancer remains a challenging disease associated with significant morbidity and mortality; however, increasing options in systemic therapy and an increasingly personalized approach to cancer treatment suggest continued future improvements in patient care.

Current and Future Landscape of Perioperative Treatment for Muscle-Invasive Bladder Cancer

Cisplatin-based neoadjuvant chemotherapy followed by radical cystectomy is the current standard of care for muscle-invasive bladder cancer (MIBC). However, less than half of patients are candidates for this treatment, and 50% will develop metastatic disease. Adjuvant chemotherapy could be offered if neoadjuvant treatment has not been administered for suitable patients. It is important to reduce the risk of systemic recurrence and improve the prognosis of localized MIBC. Systemic therapy for metastatic urothelial carcinoma has evolved in recent years. Immune checkpoint inhibitors and targeted agents, such as antibody-drug conjugates or FGFR inhibitors, are new therapeutic alternatives and have shown their benefit in advanced disease. Currently, several clinical trials are investigating the role of these drugs, as monotherapy and in combination with chemotherapy, in the neoadjuvant and adjuvant settings with promising outcomes. In addition, the development of predictive biomarkers could predict responses to neoadjuvant therapies.

Neoadjuvant immunochemotherapy in the treatment of nonmetastatic muscle-invasive bladder cancer: a systematic review

Introduction: Multiple trials are currently studying the additional effect of immunotherapy on neoadjuvant chemotherapy (NAC) in nonmetastatic muscle-invasive bladder cancer. Methods: We performed a systematic review of the literature that summarizes all ongoing trials, with their results when available. Results: From an initial 269 trials identified, 17 were included. Pathological response and pathological complete response rates of the immunotherapy + NAC combination in the cisplatin-eligible population varied between 56.6-75% and 34.0-66.7%, respectively. Two studies published their results in the cisplatin-ineligible population, with pathological complete response rates of 18 and 45.2%. Conclusion: Neoadjuvant immunochemotherapy in platinum-eligible patients results in response rates higher than those reported for NAC alone. Strong preliminary results are still lacking in the platinum-ineligible population.

Adjuvant immunotherapy for muscle-invasive urothelial carcinoma of the bladder

INTRODUCTION

There are substantial unmet needs with regards to adjuvant therapy for muscle-invasive urothelial carcinoma (UC) of the bladder, including patients with persistent disease histologically following neoadjuvant platinum-based therapy and radical resection, as well as patients who are not eligible for or refuse cytotoxic chemotherapy. As such, increased interest has been developed in advancing the use of systemic immunotherapy in the postoperative setting.

AREAS COVERED

We begin by examining current uses of systemic immunotherapy in the treatment of advanced UC. We also review emerging neoadjuvant data and describe current adjuvant approaches. We then report and analyze data on adjuvant immunotherapy, including the recent randomized trials on adjuvant nivolumab and atezolizumab, and conclude with a discussion on the available evidence and likely directions of the field.

EXPERT OPINION

Systemic immunotherapy can serve to enhance postoperative therapies for muscle-invasive bladder UC, as exemplified by the recent approval of nivolumab. Further research will serve to define optimal immunotherapy timing and combinations with other systemic therapies, as well as identify predictive biomarkers to allow effective tailoring of therapy for each patient.