Dr. Armstrong Discusses Findings of ARCHES Trial in Prostate Cancer

Andrew J. Armstrong, MD, associate professor of medicine and surgery, Department of Medicine, Duke University School of Medicine, Duke Cancer Institute, discusses findings from the phase III ARCHES trial in patients with metastatic hormone-sensitive prostate cancer.

ARCHES was a positive study, meeting its primary endpoint with a 61% delay in radiographic progression or death with the addition of enzalutamide (Xtandi) to androgen deprivation therapy (ADT) versus ADT alone. Notably, patients were stratified by volume of disease and prior exposure to docetaxel. Armstrong says that the benefit was seen across these subgroups.

For example, patients with low-volume disease experienced a delay in radiographic progression or death of approximately 70% with the addition of the androgen receptor inhibitor. Some of the key secondary endpoints that were met included a delay in the time to castration resistance, a delay in the time to prostate specific antigen progression, and a delay in the time to next antineoplastic therapy with docetaxel or abiraterone acetate (Zytiga). In addition, the quality of life of these patients was very high, which Armstrong says was one of the surprising things about ARCHES. Most patients were asymptomatic despite having high-volume disease. For example, 85% of patients had bone metastases but did not have symptoms.