The antibody-drug conjugate enfortumab vedotin-ejfv is effective in patients with muscle-invasive bladder cancer who are not eligible for cisplatin chemotherapy, according to data from cohort H of the phase IB/II EV-103 clinical trial being presented at the 2022 ASCO Genitourinary Cancers Symposium by Daniel P. Petrylak, MD, and colleagues (Abstract 435).
“Our findings showed more than one-third of patients displayed no evidence of cancer when their bladder was removed after receiving enfortumab vedotin prior to surgery,” said Dr. Petrylak, Professor of Medicine (Medical Oncology) and Urology and Co-Director of the Cancer Signaling Research Program at Yale Cancer Center, and principal investigator for the study. “The results are significant and so encouraging, as survival rates are poor for muscle-invasive bladder cancer.”
Daniel P. Petrylak, MD
Twenty-five percent of bladder cancers are diagnosed as muscle-invasive. Treatment for muscle-invasive bladder cancer typically combines cisplatin-based chemotherapy with surgery.
In the EV-103 trial, researchers enrolled patients diagnosed with muscle-invasive bladder cancer who were ineligible for cisplatin-based chemotherapy but were eligible for surgical treatment. Patients received three cycles of neoadjuvant enfortumab vedotin on days 1 and 8 of every 3-week cycle. Results from the preliminary analysis of 22 patients showed 36.4% had a pathologic complete response, the primary endpoint, displaying no signs of cancer upon microscopic examination of tissue cells removed during surgery. Half of the patients had a pathological downstaging, or reduction in tumor size. All patients underwent surgery, and there were no surgeries delayed due to treatment with enfortumab vedotin.
The most common enfortumab vedotin treatment-related adverse events were fatigue (45.5%), alopecia (36.4%), and dysgeusia (36.4%); 18.2% of patients had grade 3 or higher treatment-related adverse events.
The study authors wrote, “Observed pathological complete response rate after neoadjuvant enfortumab vedotin showed promising activity in cisplatin-ineligible pts with muscle-invasive bladder cancer who have a high unmet need. Adverse events were consistent with the known safety profile of enfortumab vedotin.”
Dr. Petrylak added, “We look forward to phase III studies to further evaluate the effectiveness of enfortumab vedotin.”
Disclosure: Funding for this study was provided by Astellas and Seagen. For full disclosures of the study authors, visit coi.asco.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.