Phase III Subgroup Analysis of Enfortumab Vedotin in Japanese Patients With Advanced Urothelial Carcinoma

By: Gavin Calabretta, BS
Posted: Thursday, November 3, 2022

In the 2020 phase III EV-301 trial, the antibody-drug conjugate enfortumab vedotin-ejfv demonstrated a significant improvement in overall survival over standard chemotherapy for patients with previously treated locally advanced or metastatic urothelial carcinoma, which supported its approval by Japan’s Ministry of Health, Labour, and Welfare in September 2021. Nobuaki Matsubara, MD, of the National Cancer Center Hospital East, Chiba, Japan, and colleagues analyzed a subgroup of Japanese patients in the EV-301 trial, aiming to inform clinicians of potential differences in response between Asian and White populations. The results, which were published in Cancer Medicine, provided efficacy and tolerability data that were consistent with the original EV-301 population.

The Japanese subgroup included 86 patients across 25 sites. All were randomly assigned to treatment with enfortumab vedotin (n = 36) or standard chemotherapy (n = 50). In the latter group, 36 individuals received docetaxel, and the remaining 12 received paclitaxel. Baseline patient characteristics were similar in comparison with the larger trial population.

Median overall survival was 15.2 and 10.6 months for enfortumab vedotin and standard chemotherapy, respectively (hazard ratio [HR] = 0.437; 95% confidence interval [CI] = 0.209–0.914). Separately, enfortumab vedotin also prolonged progression-free survival, with a median duration of 6.5 months compared with 5.4 months for standard chemotherapy (HR = 0.464; 95% CI = 0.258–0.835). Overall response rate was similarly higher with enfortumab vedotin (34.4% vs. 21.3%).

Common treatment-related adverse events included decreased neutrophil count and drug eruption for patients treated with enfortumab vedotin, and decreased neutrophil, white blood cell, and lymphocyte counts for those treated with standard chemotherapy. Of note, a smaller proportion of patients receiving enfortumab vedotin versus standard chemotherapy experienced treatment-related adverse events (91.7% vs. 97.9%).

Disclosure: For full disclosures of the study authors, visit onlinelibrary.wiley.com.

Cancer Medicine