Researchers discovered two promising new therapy options for men with recurrent prostate cancer, both of which helped patients live longer without their disease spreading than the current standard treatment.
‘If these treatments are authorized by the Food and Drug Administration, our findings will change practice,’ said Stephen Freedland, MD, associate director for Training and Education and the Warschaw, Robertson, Law Families Chair in Prostate Cancer at Cedars-Sinai and main author of the study. ‘In the research, both of these new approaches enhanced metastasis-free survival while retaining quality of life.’
Researchers at Cedars-Sinai Medical Center have uncovered two promising new therapy options for men with recurrent prostate cancer, both of which helped patients live longer without their disease advancing than the current standard treatment. Their multinational Phase-III clinical study results were published in the New England Journal of Medicine.
If these treatments are authorized by the Food and Drug Administration, our findings will change practice. In the research, both of these new approaches enhanced metastasis-free survival while retaining quality of life.
Stephen Freedland
According to the American Cancer Society, cancer of the prostate, a walnut-sized gland that aids in the production of sperm, will be detected in 288,300 men in the United States in 2023. Some people may never need treatment because they have a slow-growing form of prostate cancer, while those with more aggressive prostate cancer are frequently treated with surgery or radiation therapy first.
“Unfortunately, in about a third of those patients, the cancer recurs within 10 years,” Freedland said in a statement.
Patients with aggressive recurrence are treated with androgen deprivation therapy (ADT), also known as hormone therapy, which reduces the patient’s production of the male sex hormone testosterone. Testosterone helps prostate cancer cells grow and spread, and the hormone therapy effectively reduces the growth-stimulating effects. But Freedland said ADT has two downsides: It doesn’t completely eliminate testosterone, and it can cause many side effects.
“When you go on ADT, the testosterone level in the blood is reduced, but not completely eliminated,” Freedland said. “And the concern is that the testosterone that remains may still be enough to stimulate tumor growth. Also, patients don’t love the idea of being on hormones.”
In this analysis of 1,068 prostate cancer patients from 244 sites in 17 countries, Freedland and colleagues examined two experimental therapies, one for each of these concerns.
One-third of the patients in the randomized clinical trial received ADT plus enzalutamide, a drug that suppresses the effects of testosterone. Enzalutamide prevents any leftover testosterone in the blood from encouraging cancer cell proliferation. Another third of the individuals were given enzalutamide alone. This strategy depended on the drug to prevent the effects of testosterone even while testosterone levels in the patients’ blood were not reduced.
“We wanted to see whether enzalutamide on its own was so effective that we didn’t need the ADT,” Freedland said in a statement.
The final group of patients received ADT alone, which is the current standard treatment. Investigators found that the combination of ADT plus enzalutamide reduced the risk of metastasis or death by 58% over ADT alone. They found that enzalutamide alone reduced the risk of metastasis or death by 37% over ADT alone. Both treatments maintained quality of life relative to the ADT alone.
“While the combination therapy offers greater risk reduction, some men might prefer enzalutamide alone. It does a good job of preventing cancer spread or death, with different side effects that may be more acceptable for some men,” Freedland said. The next step is for the makers of enzalutamide to apply for FDA approval, so the experimental therapy can come into wide use, Freedland said.
“Optimizing therapy for patients with aggressive recurrence after their prostate cancer is initially treated has been an unmet need,” said Dan Theodorescu, MD, PhD, head of Cedars-Sinai Cancer and PHASE ONE Distinguished Chair. “The results of this trial point the way to two options which the study showed were more effective than current standard of care, giving these patients and their providers the opportunity to choose a potentially improved course of therapy that best meets their needs.”
