Docetaxel Boosts Survival in Patients with Hormone-Naïve Metastatic Prostate Cancer
Chicago, IL—Adding docetaxel (Taxotere) to standard hormone therapy extends overall survival (OS) by a median of 10 months versus hormone therapy alone in men with newly diagnosed, advanced, hormone therapy–naïve prostate cancer, according to the results of the STAMPEDE trial. The survival benefits were more pronounced in metastatic disease and were less certain in nonmetastatic disease. Another finding of this analysis of STAMPEDE is that zoledronic acid (Zometa) had no benefit in this setting.
“Docetaxel should be routinely used in patients with metastatic hormone-naïve prostate cancer as part of upfront treatment. In nonmetastatic disease, docetaxel should be offered to men about to start hormones for the first time, because it prolongs failure-free survival. There is some uncertainty regarding its effect on overall survival in men with nonmetastatic disease, and longer follow-up is needed,” said lead investigator Nicholas David James, MD, PhD, Founding Director of the Cancer Research Unit, University of Warwick, Coventry, England.
Dr James presented the results of the STAMPEDE trial at the 2015 American Society of Clinical Oncology (ASCO) meeting.
The STAMPEDE Trial
STAMPEDE is the largest randomized clinical trial to date in prostate cancer; it has a multiarm, adaptive design. The standard-of-care (SOC) arm continues to enroll patients on an ongoing basis, as ineffective treatments are discarded and more effective treatments are added to the SOC arm according to the trial results.
The trial includes 2962 hormone-naïve men with advanced prostate cancer who were randomized to 1 of 4 treatment arms from 9 ongoing treatment arms. The men were randomized between October 2005 and March 2013 in a 2:1:1:1 ratio to SOC, SOC with docetaxel for 6 cycles, SOC with zoledronic acid for 2 years, or to SOC with docetaxel and zoledronic acid.
In this comparison of hormone-naïve men, SOC treatment was ?3 years of androgen-deprivation therapy with local radiation for suitable patients. At a median follow-up of 42 months, 948 deaths were reported.
The OS was a median of 77 months in the docetaxel arm versus 67 months for SOC, for a 24% relative improvement in survival. The OS was longer in the subset of men with metastatic disease when docetaxel was added to hormone therapy, a difference of 22 months favoring docetaxel.
Comparing men with metastatic versus nonmetastatic disease, patients with metastatic disease had a clinically and statistically significant 37% improvement in survival, but the study was not fully powered to detect a significant survival benefit in the nonmetastatic group.
The addition of docetaxel to hormone therapy does lead to some increased toxicity, Dr James noted.
The STAMPEDE trial adds further support to the results of the CHAARTED trial, which were presented at ASCO 2014 and showed a significant survival advantage when docetaxel was added to hormone therapy in patients with hormone-sensitive advanced prostate cancer.
The current SOC for men with newly diagnosed hormone-sensitive metastatic prostate cancer should be upfront docetaxel plus hormone therapy.