Safety and efficacy of enfortumab vedotin in patients with metastatic/locally advanced urothelial cancer: Real-world evidence from a European database.

Abstract

553 Background: Enfortumab vedotin (EV) is an antibody drug conjugate targeting Nectin-4. It was approved by EMA/FDA in patients (pts) with metastatic/ locally advanced urothelial cancer post platinum and immune check point inhibitors following the results of the EV-301 trial. We report updated efficacy and safety data of EV in a large European cohort of real-world pts (GUARDIANS consortium) treated in hospitals and private practices. Methods: Retrospective data were collected from 25 German and Swiss hospitals and private practices for pts who received EV. Adverse events (AEs) were reported according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 criteria. Objective responses were evaluated by local investigators according to Response Evaluation Criteria in Solid Tumors version 1.1. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Results: Weidentified 188 pts (32.4% female) with a median age of 66 yrs (range 31-89; 22.3% >/= 75 yrs). Eastern Cooperative Oncology Group performance status (ECOG PS) was 0/1/2/3-4/unknown in 36/39/11/3/11%. EV was administered in the fourth or later line in 43% of pts. Overall response rate (ORR) was 46.3% (partial remission: 42.0%, complete response 4.3%), disease control rate was 58.0%. Median OS (mOS) was 12.0 months (mo) (95% confidence interval 9.65-14.35) and median PFS (mPFS) was 7.0 mo (95% confidence interval 5.43-8.57). Any-grade AEs were observed in 71% and CTCAE grade ≥3 AEs in 32% of pts. Most common AEs were peripheral sensory neuropathy (33.5% any grade), skin toxicity (24.5%) and fatigue (22.9%). In pts >/= 75 yrs, females, and pts treated in >/=4th line mOS, mPFS, ORR, and toxicities were comparable to younger and male counterparts and pts treated in <4th line, respectively. Limitations are retrospective design and short follow-up. Conclusions: Anti-tumor activity of EV in real-world pts including difficult-to-treat subgroups is comparable to the results of the pivotal EV-301 trial. No new safety signals were observed.