ASCO 2024: Results From EV-202 of Enfortumab Vedotin in Breast Cancer Cohorts

By: Julia Cipriano, MS
Posted: Monday, June 10, 2024

The NECTIN4-directed antibody-drug conjugate enfortumab vedotin-ejfv demonstrated antitumor activity in patients with triple-negative breast cancer, according to Antonio Giordano, MD, PhD, of Dana-Farber Cancer Institute, Boston, and colleagues. The breast cancer cohort analysis of the phase II EV-202 trial, which was presented during the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 1005), also revealed a manageable safety profile in both this population and in those with hormone receptor (HR)-positive, HER2-negative disease.

“Enfortumab vediotin is approved for use in urothelial cancer,” the investigators commented. “NECTIN4 is expressed in several solid tumors, including breast cancer.”

Heavily pretreated patients with locally advanced or metastatic triple-negative (n = 42) and HR-positive, HER2-negative (n = 45) disease received 1.25 mg/kg of intravenous enfortumab vedotin. In the triple-negative cohort (median follow-up, 11.8 months), the objective response rate was 19.0%, and the disease control rate was 57.1%. The durations of response, progression-free survival, and overall survival were 3.8, 3.5, and 12.9 months, respectively. Decreased neutrophil counts (7%), decreased white blood cell counts (5%), and increased aspartate aminotransferase levels (5%) were the most frequently reported treatment-related adverse events of grade 3 or higher. Treatment-related adverse events of special interest included skin reactions (60%), peripheral neuropathy (26%), and hyperglycemia (5%).

In the HR-positive, HER2-negative cohort (median follow-up, 11.2 months), the objective response rate was 15.6%, and the disease control rate was 51.1%. The durations of response, progression-free survival, and overall survival were 7.2, 5.4, and 19.8 months, respectively. Maculopapular rash (16%), pruritus and increased aspartate aminotransferase levels (both 7%), and abdominal pain and erythema (both 4%) were the most common treatment-related adverse events of grade 3 or higher. A total of 62%, 27%, and 11% of the cohort experienced treatment-related skin reactions, peripheral neuropathy, and hyperglycemia, respectively.  

Disclosure: Dr. Giordano has served as a consultant or advisor to Pfizer. For full disclosures of the other study authors, visit coi.asco.org.

2024 ASCO Annual Meeting

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