Avelumab First-line Maintenance Therapy for Advanced Urothelial Carcinoma: Comprehensive Clinical Subgroup Analyses from the JAVELIN Bladder 100 Phase 3 Trial

BACKGROUND

In the phase 3 JAVELIN Bladder 100 trial, avelumab first-line (1L) maintenance + best supportive care (BSC) significantly prolonged overall survival (OS) and progression-free survival (PFS) versus BSC alone in patients with advanced urothelial carcinoma (aUC) who were progression-free following 1L platinum-based chemotherapy, leading to regulatory approval in various countries.

OBJECTIVE

To analyze clinically relevant subgroups from JAVELIN Bladder 100.

DESIGN, SETTING, AND PARTICIPANTS

Patients with unresectable locally advanced or metastatic UC without progression on 1L gemcitabine + cisplatin or carboplatin were randomized to receive avelumab + BSC (n = 350) or BSC alone (n = 350). Median follow-up was >19 mo in both arms (data cutoff October 21, 2019). This trial is registered on ClinicalTrials.gov as NCT02603432.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

OS (primary endpoint) and PFS were analyzed in protocol-specified and post hoc subgroups using the Kaplan-Meier method and Cox proportional hazards models.

RESULTS AND LIMITATIONS

Hazard ratios (HRs) for OS with avelumab + BSC versus BSC alone were <1.0 across all subgroups examined, including patients treated with 1L cisplatin + gemcitabine (HR 0.69, 95% confidence interval [CI] 0.50-0.93) or carboplatin + gemcitabine (HR 0.64, 95% CI 0.46-0.90), patients with PD-L1+ tumors treated with carboplatin + gemcitabine (HR 0.67, 95% CI 0.39-1.14), and patients whose best response to chemotherapy was a complete response (HR 0.80, 95% CI 0.46-1.37), partial response (HR 0.62, 95% CI 0.46-0.84), or stable disease (HR 0.70, 95% CI 0.46-1.06). Observations were similar for PFS. Limitations include the smaller size and post hoc evaluation without multiplicity adjustment for some subgroups.

CONCLUSIONS

Analyses of OS and PFS in clinically relevant subgroups were consistent with results for the overall population, further supporting avelumab 1L maintenance as standard-of-care treatment for patients with aUC who are progression-free following 1L platinum-based chemotherapy.

PATIENT SUMMARY

In the JAVELIN Bladder 100 study, maintenance treatment with avelumab helped many different groups of people with advanced cancer of the urinary tract to live longer.

Immunotherapy for Urothelial Carcinoma: Focus on Clinical Utility of Nivolumab

Over the past decade, the emergence of immune checkpoint inhibitors has brought about significant change to the treatment landscape of bladder cancer. Nivolumab is an immune checkpoint inhibitor that has shown favorable results resulting in FDA approval for treatment of platinum-refractory locally advanced or metastatic urothelial carcinoma. More recently, it was the first (and only) immune checkpoint inhibitor to receive FDA approval for the treatment of urothelial carcinoma in the adjuvant setting after radical surgery. Multiple trials are now actively underway to further understand the nuances in which immune checkpoint inhibitors such as nivolumab can be beneficial. In this review, we explore the development of nivolumab in terms of its mechanism of action, its growing indications in the treatment of urothelial carcinoma, and potential future directions for clinical trials. Immune checkpoint inhibitors are a promising treatment for bladder cancer, but further work is needed to continue to improve outcomes for patients.