Astellas Pharma Inc. and Seattle Genetics Inc. reported that based on data from an ongoing phase 1 trial for enfortumab vedotin as a monotherapy against metastatic urothelial cancer, they will enroll patients this year for a pivotal phase 2 trial.
Data presented at the American Society of Clinical Oncology annual meeting shows that 4% of 71 patients evaluated for response had complete remission while 37% had partial remission of the disease over the course of the ongoing phase 1 study.
Enfortumab vedotin is an investigational antibody-drug conjugate targeting a cell surface protein that appears in a range of tumors, including some in metastatic urothelial cancer, ovarian cancer and non-small cell lung cancer. The phase 2 trial will focus on patients with metastatic urothelial cancer that has previously been treated with checkpoint inhibitor therapies.
In the phase 1 trial, 14 patients in this previous treatment group, or 44% of the total, had an objective response, including one complete response and 13 partial responses.
The companies said that in the 19 patients with liver metastases, eight showed partial remission while one showed complete remission.