Long-term Outcomes from a Phase 2 Study of Neoadjuvant Chemotherapy for Muscle-invasive Bladder Cancer (SWOG S1314; NCT02177695)

Impact of Immune Checkpoint Inhibitors as Neoadjuvant Therapy for Muscle-invasive Bladder Cancer: A Systematic Review, Meta-analysis, and Network Meta-analysis

BACKGROUND AND OBJECTIVE

The availability of immune checkpoint inhibitors (ICIs) has expanded perioperative treatment options for urothelial carcinoma. Our aim was to evaluate the effect of neoadjuvant ICI-based regimens on oncological outcomes for patients with muscle-invasive bladder cancer (MIBC).

METHODS

We systematically searched MEDLINE, Embase, Web of Science, and ClinicalTrials.gov in September 2024 for studies on neoadjuvant therapies for MIBC. A proportion meta-analysis and network meta-analysis (NMA) using random-effect models were conducted to evaluate pooled pathological complete response (pCR) rates and to compare overall survival (OS) and adverse events. The review is registered on PROSPERO (CRD42024587964).

KEY FINDINGS AND LIMITATIONS

We included 12 randomized controlled trials (RCTs; 5004 patients) and 35 non-RCTs (2964 patients). ICI-chemotherapy combination therapy was associated with a significantly higher pCR rate versus chemotherapy alone (40.6% vs 17.9%; p < 0.01). In the two phase 3 RCTs included (1556 patients) there was no significant difference in OS between dose-dense methotrexate + vinblastine + Adriamycin + cisplatin (ddMVAC) and durvalumab + gemcitabine + cisplatin (GC; hazard ratio 1.06, 95% confidence interval [CI] 0.72-1.55; p = 0.8). ddMVAC significantly increased the risk of grade ≥3 anemia (risk ratio [RR] 2.81, 95% CI 1.62-4.88) and asthenia (RR 3.46, 95% CI 1.68-7.14) in comparison to GC, while durvalumab + GC did not. Limitations include data heterogeneity across studies and the limited number of studies included in the NMA.

CONCLUSIONS AND CLINICAL IMPLICATIONS

ICI addition to chemotherapy in the neoadjuvant MIBC setting significantly increased pCR rates in comparison to chemotherapy alone. However, there was no difference in OS between durvalumab + GC and ddMVAC. Further studies are needed to clarify the OS benefit of ICI-based combination therapy in comparison to the current standard chemotherapy regimen.

Advancements in systemic therapy for muscle-invasive bladder cancer: A systematic review from the beginning to the latest updates

Context

Several phase III randomized controlled trials (RCTs) have shown the importance of perioperative systemic therapy, especially for the efficacy of immune checkpoint inhibitors (ICIs) in both neoadjuvant and adjuvant settings for muscle-invasive bladder cancer (MIBC).

Objective

To synthesize the growing evidence on the efficacy and safety of systemic therapies for MIBC utilizing the data from RCTs.

Evidence acquisition

Three databases and ClinicalTrials.gov were searched in October 2024 for eligible RCTs evaluating oncologic outcomes in MIBC patients treated with systemic therapy. We evaluated pathological complete response (pCR), disease-free survival (DFS), progression-free survival (PFS), event-free survival (EFS), overall survival (OS), and adverse events (AEs).

Evidence synthesis

Thirty-three RCTs (including 14 ongoing trials) were included in this systematic review. Neoadjuvant chemotherapy improved OS compared to radical cystectomy alone. Particularly, the VESPER trial demonstrated that dd-MVAC provided oncological benefits over GC alone in terms of pCR rates, OS (HR: 0.71), and PFS (HR: 0.70). Recently, the NIAGARA trial showed that perioperative durvalumab plus GC outperformed GC alone in terms of pCR rates, OS (HR: 0.75), and EFS (HR: 0.68). Despite the lack of data on overall AE rates in the VESPER trial, differential safety profiles in hematologic toxicity were reported between dd-MVAC and durvalumab plus GC regimens. In the adjuvant setting, no study provided the OS benefit from adjuvant chemotherapy. However, only adjuvant nivolumab had significant DFS and OS benefits compared to placebo.

Conclusions

Neoadjuvant chemotherapy remains the current standard of care for MIBC. Durvalumab shed light on the promising impact of ICIs added to neoadjuvant chemotherapy. Nivolumab is the only ICI recommended as adjuvant therapy in patients who harbored adverse pathologic outcomes. Ongoing trials will provide further information on the impact of combination therapy, including chemotherapy, ICIs, and enfortumab vedotin, in both neoadjuvant and adjuvant settings.

Predicting response to neoadjuvant chemotherapy in muscle-invasive bladder cancer via interpretable multimodal deep learning

Building accurate prediction models and identifying predictive biomarkers for treatment response in Muscle-Invasive Bladder Cancer (MIBC) are essential for improving patient survival but remain challenging due to tumor heterogeneity, despite numerous related studies. To address this unmet need, we developed an interpretable Graph-based Multimodal Late Fusion (GMLF) deep learning framework. Integrating histopathology and cell type data from standard H&E images with gene expression profiles derived from RNA sequencing from the SWOG S1314-COXEN clinical trial (ClinicalTrials.gov NCT02177695 2014-06-25), GMLF uncovered new histopathological, cellular, and molecular determinants of response to neoadjuvant chemotherapy. Specifically, we identified key gene signatures that drive the predictive power of our model, including alterations in TP63, CCL5, and DCN. Our discovery can optimize treatment strategies for patients with MIBC, e.g., improving clinical outcomes, avoiding unnecessary treatment, and ultimately, bladder preservation. Additionally, our approach could be used to uncover predictors for other cancers.

Phase II Trial of Risk-Enabled Therapy After Neoadjuvant Chemotherapy for Muscle-Invasive Bladder Cancer (RETAIN 1)

PURPOSE

Cisplatin-based neoadjuvant chemotherapy (NAC) followed by cystectomy is the standard of care for patients with muscle-invasive bladder cancer (MIBC). Mutations in DNA damage repair genes are associated with pathologic downstaging after NAC. We hypothesized that a combination of biomarker selection and clinical staging would identify patients for cystectomy-sparing active surveillance (AS).

PATIENTS AND METHODS

We conducted a single-arm, phase II, noninferiority trial to evaluate a risk-adapted approach for MIBC. Patients with cT2-T3N0M0 MIBC underwent NAC with accelerated methotrexate, vinblastine, doxorubicin, and cisplatin (AMVAC). Pre-NAC transurethral bladder tumor specimens were sequenced for mutations in ATM, ERCC2, FANCC, and RB1. Patients with ≥1 mutation and cT0 post-NAC began AS. The primary end point was metastasis-free survival (MFS) at 2 years for the entire cohort with the null hypothesis rejected if the lower bound exact one-sided 95% CI exceeds 64%.

RESULTS

Seventy patients were enrolled, 33 (47%) had a mutation, and 25 (36%) began per-protocol AS. With a median follow-up of 40 months, the 2-year MFS for all patients was 72.9% (lower bound exact one-sided 95% CI, 62.8). The 2-year MFS was 76.0% in the AS group (95% CI, 54.2 to 88.4) and 71.1% (95% CI, 55.5 to 82.1) in the remaining patients. In the AS group, 17 patients (68%) had some recurrence and 12 (48%) were metastasis-free with an intact bladder. The 2-year overall survival (OS) was 84.3% (95% CI, 73.4 to 91.0); OS was 88.0% (95% CI, 67.3 to 96.0) and 82.2% (95% CI, 67.6 to 90.7) in the AS and not-AS groups, respectively.

CONCLUSION

Patients with MIBC treated with AMVAC followed by a risk-adapted approach to local consolidation achieved a 2-year MFS rate of 73%. The primary end point was not met, but 17% of all enrolled patients and 48% of the AS group avoided cystectomy without metastatic disease.

[Can muscle invasive bladder cancer be treated without cystectomy in the future? : New data on trimodal therapy and bladder preservation after systemic therapy alone]

Muscle invasive bladder cancer is generally an aggressive disease. Radical cystectomy (RC) is traditionally the treatment of choice. Due to possible advantages in morbidity, peri-interventional mortality, and quality of life, bladder-preserving treatment strategies are of interest. Here, trimodal therapy (TMT) consisting of maximum transurethral resection and subsequent radiochemotherapy with subsequent cystoscopic follow-up plays an important role. Current cohort analyses indicate equivalent oncological results of TMT to RC in selected patients. However, the use of systemic therapy alone with combined chemo-/immunotherapy or cytotoxic combination therapy also shows promising efficacy both in early surrogate parameters and in oncological endpoints. Overall, studies to date suggest that bladder preservation is possible without compromising oncologic outcomes. Future developments aim to refine patient selection by combining different risk factors and biomarkers to further improve outcomes.

Advancements in Urothelial Cancer Care: Optimizing Treatment for Your Patient

The standard treatment paradigm for muscle invasive bladder cancer has been neoadjuvant cisplatin-based chemotherapy followed by radical cystectomy. However, efforts are ongoing to personalize treatment by incorporating biomarkers to better guide treatment selection. In addition, bladder preservation strategies are aimed at avoiding cystectomy in well-selected patients. Similarly, in the metastatic urothelial cancer space, the standard frontline treatment option of platinum-based chemotherapy has changed with the availability of data from EV-302 trial, making the combination of enfortumab vedotin (EV) and pembrolizumab the preferred first-line treatment option. Here, we examine the optimization of treatment intensity and sequencing, focusing on the challenges and opportunities associated with EV/pembrolizumab therapy, including managing toxicities and exploring alternative dosing approaches. Together, these articles provide a comprehensive overview of contemporary strategies in bladder cancer management, highlighting the importance of individualized treatment approaches, ongoing research, and multidisciplinary collaboration to improve patient outcomes in this complex disease landscape.

Neoadjuvant Cisplatin-based Chemotherapy in Nonmetastatic Muscle-invasive Bladder Cancer: A Systematic Review and Pooled Meta-analysis to Determine the Preferred Regimen

OBJECTIVE

To determine whether neoadjuvant gemcitabine and cisplatin (GC) vs dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (ddMVAC) before radical cystectomy improves overall survival (OS), progression-free survival (PFS), and pathologic complete response (pCR) for patients with muscle-invasive bladder cancer with secondary analyses of pathological downstaging and toxicity.

MATERIALS AND METHODS

This systematic review and meta-analysis identified studies of patients with muscle-invasive bladder cancer treated with neoadjuvant GC compared to ddMVAC from PubMed, Web of Science, and EMBASE. Random-effect models for pooled log-transformed hazard ratios (HR) for OS and PFS and pooled odds ratios for pCR and downstaging were developed using the generic inverse variance method and Mantel-Haenszel method, respectively.

RESULTS

Ten studies were identified (4 OS, 2 PFS, and 6 pCR clinical endpoints). Neoadjuvant ddMVAC improved OS (HR 0.71 [95% confidence intervals 0.56; 0.90]), PFS (HR 0.76 [95% confidence intervals 0.60; 0.97]), and pathological downstaging (odds ratio 1.34 [95% confidence interval 1.01; 1.78]) as compared to GC. There was no significant difference between regimens for pCR rates (odds ratio 1.38 [95% confidence interval 0.90; 2.12]). Treatment toxicity was greater with ddMVAC. Limitations result from differences in number of ddMVAC cycles and patient selection between studies.

CONCLUSION

Neoadjuvant ddMVAC is associated with improved OS and PFS vs gemcitabine/cisplatin for patients with muscle-invasive bladder cancer before radical cystectomy. Although rates of pathological complete response were not significantly different, pathological downstaging correlated with OS. ddMVAC should be preferred over gemcitabine/cisplatin for patients with muscle-invasive bladder cancer who can tolerate its greater toxicity.