Real-World Evidence of Tumor and Patient Characteristics and Survival with Avelumab Maintenance after Chemotherapy for Advanced and Metastatic Urothelial Carcinoma.

INTRODUCTION

Despite the prospective randomized controlled JAVELIN Bladder 100 trial, no real-world evidence exists regarding tumor characteristics, adverse events (AEs), and survival of avelumab maintenance (AVM)-treated patients with partial/complete response or stable disease after previous platinum-based chemotherapy for advanced/metastatic urothelial carcinoma (mUC).

METHODS

We relied on our institutional database to identify mUC patients who received AVM between January, 2021 and December, 2023. The main outcomes consisted of overall survival (OS) and progression-free survival (PFS) and were computed by Kaplan-Meier estimates. Stratification was performed according to programmed death ligand 1 (PD-L1) status.

RESULTS

Overall, 24 AVM patients were identified at a median age of 71 (interquartile range [IQR]: 67-76) years, of which 67% were males. Of these, 63%, 21%, and 17% received AVM therapy for bladder cancer and upper tract urothelial carcinoma or both, respectively. PD-L1 status was positive in 45% of patients. During AVM treatment, AEs were observed in 33% of patients; however, they were limited to ≤2 grade AEs. At a median follow-up of eight (IQR 4-20) months, 71% of patients had progressed under AVM with median PFS of 6.2 months (confidence interval [CI]: 3.2-18.2). Median OS was 13.4 (CI: 6.9 - not reached [NR]) months. One-year OS after AVM was 52%. In PD-L1-positive patients, median PFS and OS were 6.4 (CI: 2.7 - NR) months and 13.4 (CI: 7.7 months - NR), respectively.

CONCLUSION

AVM is associated with moderate AE rates. Despite similarities in baseline characteristics compared to trial-selected JAVELIN Bladder 100 mUC patients, AVM resulted in longer/similar PFS but significantly shorter OS in real-world setting.