Late Breaking Abstract – ASCO 2020: FDA Approves BAVENCIO® for Maintenance Treatment in Advanced Urothelial Carcinoma

SUMMARY: The FDA on June 30, 2020 approved BAVENCIO® for maintenance treatment of patients with locally advanced or metastatic Urothelial Carcinoma (UC) that has not progressed with first-line platinum-containing chemotherapy. The American Cancer Society estimates that for 2020, about 81,400 new cases of bladder cancer will be diagnosed in the US and about 17,980 patients will die of the disease. Bladder cancer is the fourth most common cancer in men, but is less common in women, and the average age at the time of diagnosis is 73. Patients with advanced Urothelial Carcinoma are currently treated in the first line setting with a Platinum based chemotherapy regimen. Progression Free Survival (PFS) and Overall Survival (OS) however are generally short because of resistance to chemotherapy. Treatment options for patients who progress after Platinum based chemotherapy are limited, with poor outcomes. The response rates with standard chemotherapy in this patient population, is about 10%.

BAVENCIO® (Avelumab) is a human, immunoglobulin G1 lambda, PD-L1 targeted monoclonal antibody that binds to PD-L1 and blocks the interaction between PD-L1 and its receptor PD-1. This in turn negates the inhibitory effects of PD-L1 on the immune response by unleashing the immune system and restoring antitumor immune responses. In addition, BAVENCIO® induces Antibody Dependent Cell-mediated Cytotoxicity (ADCC). BAVENCIO® was previously granted an accelerated approval by the FDA in 2017 for the treatment of patients with locally advanced or metastatic Urothelial Carcinoma who have disease progression during or following Platinum-containing chemotherapy.

JAVELIN Bladder 100 study is an international, multicenter, open-label, parallel-arm, randomized Phase III trial, which evaluated BAVENCIO® as maintenance therapy following response or stable disease with first-line Platinum-based chemotherapy, in patients with advanced Urothelial Carcinoma. This study included 700 patients with unresectable locally advanced or metastatic Urothelial Cancer, whose disease did not progress following 4 to 6 cycles of standard Gemcitabine with either Cisplatin or Carboplatin. These patients were randomly assigned 1:1 to receive maintenance BAVENCIO® 10 mg/kg IV every 2 weeks in 4 week cycles plus Best Supportive Care (N=350) or BSC alone (N=350). Best Supportive Care included symptom control and pain management, supportive nutrition, correction of metabolic disorders and antibiotics if indicated. Patients were stratified by best response to first-line chemotherapy (Complete vs Partial Response vs stable disease), and by visceral vs non-visceral disease, when initiating first-line chemotherapy. Across the study population, 51% of patients had tumors that were PD-L1 positive. The Coprimary end points were Overall Survival (OS) in all randomized patients, and in those with PD-L1 positive tumors. Secondary end points included Progression Free Survival (PFS), Objective Response Rate (ORR), and safety. The median follow up was 19.6 months for the BAVENCIO® cohort and 19.2 months for the BSC-alone cohort.

The combination of BAVENCIO® plus BSC significantly prolonged OS, compared with BSC alone, in all randomized patients (HR=0.69; P=0.0005), suggesting a 31% reduction in the risk of death with the addition of  maintenance BAVENCIO®. The median OS was 21.4 months with BAVENCIO® plus BSC compared with 14.3 months with BSC alone. Significantly prolonged OS with BAVENCIO® plus BSC, compared with BSC alone, was also noted among patients with PD-L1 positive tumors, and the median OS was not reached in the BAVENCIO® group versus 17.1 months in the control group (HR=0.56; P=0.0003). The OS benefit with BAVENCIO® was noted across all prespecified subgroups, including those defined by Cisplatin-based or Carboplatin-based chemotherapy, and regardless of whether response or stable disease was reached after first-line induction chemotherapy. Based on blinded Independent Central Review, the median PFS favored the BAVENCIO® group both in the overall randomized population (3.7 months versus 2 months, HR=0.62; P<0.001) as well as in the PD-L1 positive subgroup (HR=0.56). All-grade Adverse Events occurred in 98% of the BAVENCIO® group versus 77.7% of the control group, and grade 3/4 AEs occurred in 47.4% versus 25.2%, respectively.

It was concluded that this study met its primary objective, demonstrating significantly prolonged Overall Survival with first-line maintenance BAVENCIO® plus BSC compared with BSC alone, in all patients with advanced Urothelial Carcinoma, and should therefore be the new first-line standard of care in this patient group.

Maintenance avelumab + best supportive care (BSC) versus BSC alone after platinum-based first-line (1L) chemotherapy in advanced urothelial carcinoma (UC): JAVELIN Bladder 100 phase III interim analysis. Powles T, Park SH, Voog E, et al. J Clin Oncol 38: 2020 (suppl; abstr LBA1)