Updates in prostate cancer: ASCO GU 2014
PUBLISHED FRIDAY, FEBRUARY 7, 2014
This year marks the 10th anniversary of the oncology meeting devoted to genitourinary cancers, which includes prostate, kidney and bladder. The American Society of Clinical Oncology's Genitourinary Cancers Symposium (gucasym.org), held Jan. 30 to Feb. 1 in San Francisco, presented several studies that may impact clinical practice and future research in prostate cancer. Here are a few notable findings:
Xtandi, Given Before Chemo, Extends Survival in Patients with Advanced Prostate Cancer
Men with advanced prostate cancer are typically given hormone therapy (androgen deprivation) until the disease progresses, whereas the next option is usually chemotherapy. Because prostate cancer is generally a slow-growing disease, delaying time to chemotherapy has been one goal in treatment. Xtandi (enzalutamide), an oral drug that blocks the androgen receptor, was approved in 2012 after it was shown to extend survival for men whose metastatic, castration-resistant prostate cancer had progressed on docetaxel.
The results of the phase 3 PREVAIL study showed that when men were given Xtandi before chemotherapy, the drug delayed disease progression, improved survival, delayed time to chemotherapy and improved quality of life.
The trial randomized more than 1,700 men who had few or no symptoms of their advanced prostate cancer to receive Xtandi or a placebo. Overall, Xtandi delayed the time to chemotherapy by about 17 months. Side effects were minimal and similar in both groups of patients and included fatigue, back pain, constipation and hypertension.
The interim results of the study clearly showed the benefit of Xtandi, which led an independent data monitoring committee to recommend that the trial be stopped early and patients receiving placebo be offered the investigational drug.
"I think it's safe to say that enzalutimde provided a significant clinical benefit to patients with metastatic castration-resistant prostate cancer," said Tomasz Beer, lead author of the study, as he concluded the presentation.
After disease progression, participants in the trial went on to other therapies, including docetaxel, Zytiga (abiraterone), Jevtana (cabazitaxel), Xtandi, and Provenge (sipuleucel-T), many of which were approved in the past few years--a testament to the advances occurring in prostate cancer treatment.
Yervoy in Prostate Cancer
Researchers presented findings from a study of Yervoy (ipilimumab), an immunotherapy that helps the body's own immune system attack the cancer. Approved for melanoma, Yervoy is being tested in several different cancer types, including prostate cancer.