New Data Shows Added Benefits for Prostate Cancer Drug Enzalutamide
From this year’s European Society for Medical Oncology (ESMO) Congress in Vienna September 28-October 2, 2012
Abstract Title: Impact of enzalutamide, an androgen receptor signaling inhibitor, on time to first skeletal related event (sre) and pain in the phase 3 affirm study
October 05, 2012 -- Enzalutamide is a recently FDA-approved drug for men with an advanced form of prostate cancer known as castration-resistant prostate cancer (CRPC), who had been treated previously with docetaxel chemotherapy. CRPC is a stage of cancer when the cancer grows despite limited amounts of testosterone, a male androgen hormone, in the blood. (Androgens can fuel prostate cancer progression.) CRPC is also known as treatment-resistant prostate cancer due to its resistance to drugs that lower the level of testosterone in the blood. Enzalutamide is an androgen inhibitor that has been shown to prolong median overall survival by about five months.
This week, at the annual meeting of the European Society for Medical Oncology in Vienna, researchers released additional data from the large trial, known as AFFIRM, that provided the original data on enzalutamide’s survival benefit to men with CRPC. New benefits of the drug were shown to be delayed time to complications from bone metastases—such complications are known as skeletal-related events--and reduction in subjective pain scores in men with CRPC.
“In addition to prolonging survival and delaying cancer progression and achieving PSA declines, we now have data on skeletal-related events and pain, two clinically meaningful events,” said Dr. Philip Kantoff, the director of The Lank Center for Genitourinary Oncology, and chief of the division of solid tumor oncology at the Dana-Farber Cancer Institute, who was not involved in the study. “This new data adds to the arsenal of information we have on the effectiveness of enzalutamide,” said Kantoff.
The AFFIRM trial was a multinational Phase III double-blind trial that randomized CRPC patients who had completed treatment with docetaxel to either enzalutamide or placebo. In their presentation at ESMO, the AFFIRM researchers reported that men who received the anti-androgen drug delayed the time to their first skeletal-related event by 3.4 months. Reported pain decreases of 30 percent or greater were achieved by 45 percent of men receiving the drug compared to 7 percent of the men on placebo.
Drs. Johann de Bono of the Institute of Cancer Research in the UK and Howard I. Scher of the Memorial Sloan-Kettering Cancer Center in New York—both of whom are authors on the AFFIRM study-- are PCF-funded investigators.