The impact of prior platinum therapy on survival in patients with metastatic urothelial cancer receiving vinflunine

Second-Line Systemic Treatment for Metastatic Urothelial Carcinoma: A Network Meta-Analysis of Randomized Phase Clinical Trials

Purpose: We aimed to evaluate and compare relative impacts of various second-line treatments on overall survival (OS) in metastatic urothelial carcinoma (mUC).

Method: A literature search was conducted in PubMed, Embase, and the Cochrane Library for all articles published prior to December 2018 in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Seven randomized controlled trials with phase III design that met study eligibility criteria were selected for final analysis. A Bayesian framework network meta-analysis (NMA) was applied to indirectly compare the effect of each treatment on OS.

Results: In NMA, atezolizumab (HR, 0.90; 95% CI, 0.57–1.40) and pembrolizumab (HR, 0.77, 95% CI, 0.48–1.20) showed no significant effect on OS improvement compared to vinflunine. Gemcitabine/paclitaxel combination (HR, 1.30; 95% CI, 0.80–1.90) and lapatinib (HR, 0.95; 95% CI, 0.57–1.60) was not significantly associated with OS improvement compared to atezolizumab and best supportive care, respectively. However, results of rankograms revealed that pembrolizumab and atezolizumab were the first and second rank therapeutic agents for OS improvement in post-platinum mUC.

Conclusions: Our NMA results are inconclusive. The optimal second-line treatment for OS improvement could not be determined because there were no significant OS differences among evaluated therapeutic agents. However, the use of immunotherapeutic agents such as atezolizumab and pembolizumab may have priority for improving OS in second-line setting of mUC.

Vinflunine for the treatment of advanced or metastatic transitional cell carcinoma of the urothelial tract: an evidence-based review of safety, efficacy, and place in therapy

Background

A systematic review and meta-analysis of the use of systemic vinflunine (VIN) in the treatment of urothelial carcinoma (UC) was performed to evaluate its efficacy based on current available clinical data.

Methods

This review was prospectively registered at the International Prospective Register of Systematic Reviews, PROSPERO (registration CRD42016049294). Electronic databases including MEDLINE^®, Embase^®, Cochrane Central Register of Controlled Trials, and Web of Science were searched through December 2016. We performed a meta-analysis of the published data. Primary end points were progression-free survival (PFS) and overall survival (OS). Numerous secondary clinical outcomes were analyzed including response and toxicity data.

Results

We identified 382 publications, of which 35 met inclusion criteria for this review representing 29 unique studies. A total of 2,255 patients received VIN for the treatment of UC in the included studies. OS and PFS were analyzed in a pooled Kaplan–Meier analysis. Response data were available for 1,416 VIN-treated patients with random effects proportion of complete response in 1%, partial response in 18%, and overall response rate of 21%. Toxicity analysis revealed fatigue (40.1%), nausea (33.9%), constipation (34.1%), and alopecia (26.0%) as the most prevalent overall non-hematologic adverse events (AEs). Most prevalent grade 3–4 AEs were fatigue (10.2%), abdominal pain (8.2%), myalgias (2.5%), and nausea (2.3%). Most common hematologic AEs of all grades were anemia (56.6%), neutropenia (46.0%), thrombocytopenia (25.5%), and febrile neutropenia (6.6%). Grade 3–4 hematologic AEs had the following pooled rates: neutropenia, 24.6%; anemia, 10.2%; febrile neutropenia, 5.4%; and thrombocytopenia, 3.0%.

Conclusion

VIN has been explored as a combination first-line treatment as well as a single-agent second-line, third-line, and maintenance therapy for advanced and metastatic UC. In first-line treatment of UC, either as a maintenance agent after cisplatin or as a primary combination therapy, VIN may be a promising alternative to current treatments. Further studies are needed to compare first-line combination VIN regimens to the current standard of care in order to assess long-term survival outcomes. Second- and third-line VIN monotherapy does provide a proven, although limited, survival benefit in platinum-refractory patients.

Systemic chemotherapy in muscle invasive and metastatic bladder cancer: present and future

Bladder cancer is the most frequent among the urothelial tumors, and it is responsible for about 2% of all cancer mortality worldwide. The mainstay of chemotherapy treatment, both for muscle-invasive and metastatic disease, is cisplatin-based regimens. In recent years, ground-breaking results have been achieved with immunotherapy, which have led to important breakthroughs in the bladder cancer treatment scenario, with the approval of several new agents. New insights derive from a greater characterization of the tumor genome, which could lead to developing new therapies, more personalized, in the near future.

Impact of Prior Platinum-Based Therapy on Patients Receiving Salvage Systemic Treatment for Advanced Urothelial Carcinoma

BACKGROUND

Trials of salvage therapy for advanced urothelial carcinoma have required prior platinum-based therapy. This practice requires scrutiny because non-platinum-based first-line therapy may be offered to cisplatin-ineligible patients.

PATIENTS AND METHODS

Data of patients receiving salvage systemic chemotherapy were collected. Data on prior first-line platinum exposure were required in addition to treatment-free interval, hemoglobin, Eastern Cooperative Oncology Group performance status, albumin, and liver metastasis status. Cox proportional hazard regression was used to evaluate their association with overall survival (OS) after accounting for salvage single-agent or combination chemotherapy.

RESULTS

Data were obtained from 455 patients previously exposed to platinum-based therapy and 37 not exposed to platinum. In the group exposed to prior platinum therapy, salvage therapy consisted of a single-agent taxane (n = 184) or a taxane-containing combination chemotherapy (n = 271). In the group not exposed to prior platinum therapy, salvage therapy consisted of taxane or vinflunine (n = 20), 5-fluorouracil (n = 1), taxane-containing combination chemotherapy (n = 12), carboplatin-based combinations (n = 2), and cisplatin-based combinations (n = 2). The median OS for the prior platinum therapy group was 7.8 months (95% confidence interval, 7.0, 8.1), and for the group that had not received prior platinum therapy was 9.0 months (95% confidence interval, 6.0, 11.0; P = .50). In the multivariable analysis, prior platinum therapy versus no prior platinum exposure did not confer an independent impact on OS (hazard ratio, 1.10; 95% confidence interval, 0.75, 1.64; P = .62).

CONCLUSION

Prior platinum- versus non-platinum-based chemotherapy did not have a prognostic impact on OS after accounting for major prognostic factors in patients receiving salvage systemic chemotherapy for advanced urothelial carcinoma. Lack of prior platinum therapy should not disqualify patients from inclusion onto trials of salvage therapy.

Treatment of relapsed urothelial bladder cancer with vinflunine: real-world evidence by the Hellenic Genitourinary Cancer Group

Relapsed urothelial cancer represents an unmet medical need. Vinflunine is a third-generation antimicrotubuline inhibitor and is currently the only approved drug for second-line treatment across the European Union. We conducted a retrospective analysis assessing the efficacy and safety of vinflunine in 71 Greek patients with relapsed urothelial cancer who were treated between 2005 and 2014. An overall 84% of our patients received vinflunine as second-line treatment, 77% had a performance status of Eastern Cooperative Oncology Group scale 0 or 1, and 30% had liver metastasis at the time of vinflunine administration. A median of four cycles of vinflunine were administered (range 1–16). The most common reported adverse events were constipation, fatigue, and anemia. Median progression-free survival was 6.2 months (95% confidence interval: 4.4–8.8) and overall survival was 11.9 months (95% confidence interval: 7.4–21). Two patients (3%) achieved a complete remission, seven a partial remission (10%), and 22 (31%) had stable disease according to an intention-to-treat analysis. Hemoglobin level less than 10 g/dl and Eastern Cooperative Oncology Group performance status greater than 1 were independent adverse prognostic factors. Stratification according to the Bellmunt risk model was also associated with progression-free survival and overall survival in our population. Vinflunine appears to be a safe and effective treatment modality for relapsed urothelial cancer. More effective therapies and more accurate prognostic algorithms should be sought.

Single-agent Taxane Versus Taxane-containing Combination Chemotherapy as Salvage Therapy for Advanced Urothelial Carcinoma

BACKGROUND

Single-agent taxanes are commonly used as salvage systemic therapy for patients with advanced urothelial carcinoma (UC).

OBJECTIVE

To study the impact of combination chemotherapy delivering a taxane plus other chemotherapeutic agents compared with single-agent taxane as salvage therapy.

DESIGN, SETTING, AND PARTICIPANTS

Individual patient-level data from phase 2 trials of salvage systemic therapy were used.

INTERVENTIONS

Trials evaluating either single agents (paclitaxel or docetaxel) or combination chemotherapy (taxane plus one other chemotherapeutic agent or more) following prior platinum-based therapy were used.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Information regarding the known major baseline prognostic factors was required: time from prior chemotherapy, hemoglobin, performance status, albumin, and liver metastasis status. Cox proportional hazards regression was used to evaluate the association of prognostic factors and combination versus single-agent chemotherapy with overall survival (OS).

RESULTS AND LIMITATIONS

Data were available from eight trials including 370 patients; two trials (n=109) evaluated single-agent chemotherapy with docetaxel (n=72) and cremophor-free paclitaxel (n=37), and six trials (n=261) evaluated combination chemotherapy with gemcitabine-paclitaxel (two trials, with n=99 and n=24), paclitaxel-cyclophosphamide (n=32), paclitaxel-ifosfamide-nedaplatin (n=45), docetaxel-ifosfamide-cisplatin (n=26), and paclitaxel-epirubicin (n=35). On multivariable analysis after adjustment for baseline prognostic factors, combination chemotherapy was independently and significantly associated with improved OS (hazard ratio: 0.60; 95% confidence interval, 0.45-0.82; p=0.001). The retrospective design of this analysis and the trial-eligible population were inherent limitations.

CONCLUSIONS

Patients enrolled in trials of combination chemotherapy exhibited improved OS compared with patients enrolled in trials of single-agent chemotherapy as salvage therapy for advanced UC. Prospective randomized trials are required to validate a potential role for rational and tolerable combination chemotherapeutic regimens for the salvage therapy of advanced UC.

PATIENT SUMMARY

This retrospective study suggests that a combination of chemotherapy agents may extend survival compared with single-agent chemotherapy in selected patients with metastatic urothelial cancer progressing after prior chemotherapy.

Second-line therapies in metastatic urothelial carcinoma

Patients with relapsed or refractory urothelial carcinoma (UC) face a poor prognosis and a dearth of available treatment options that improve their survival. End-organ function and performance status play a vital role in the choice of second-line therapies. Evidence supporting the use of cytotoxic chemotherapy, as single agents or in combination, arises from small phase 2 studies with modest responses. With the evolution of genomic testing in UC, several pathways amenable to available targeted therapies have emerged. Encouraging patient participation in clinical trials is critical to improve patient outcomes and to advance the current modest treatment armamentarium.