Cedars-Sinai Cancer investigators have identified two promising recent treatment options for men with recurrent prostate cancer-; each of which helped patients live longer without their disease progressing than the present standard treatment. The outcomes of their international Phase III clinical trial were published today within the Recent England Journal of Medicine.

If these treatments are approved by the Food and Drug Administration, our results shall be practice changing. Within the study, each of those recent options improved metastasis-free survival while preserving quality of life.”

Stephen Freedland, MD, associate director for Training and Education and the Warschaw, Robertson, Law Families Chair in Prostate Cancer at Cedars-Sinai, and lead creator of the study

Cancer of the prostate, a walnut-sized gland that helps make semen, shall be diagnosed in 288,300 men within the U.S. in 2023, in line with American Cancer Society estimates. For some, treatment may never be needed because they’ve a slow-growing type of the disease, but those with more aggressive prostate cancer are sometimes first treated with surgery or radiation therapy.

“Unfortunately, in a few third of those patients, the cancer recurs inside 10 years,” Freedland said.

Patients with aggressive reoccurrence are treated with androgen deprivation therapy (ADT), also often called 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 could actually cause many uncomfortable side effects.

“Once you go on ADT, the testosterone level within the blood is reduced, but not completely eliminated,” Freedland said. “And the priority is that the testosterone that is still should still be enough to stimulate tumor growth. Also, patients don’t love the concept of being on hormones.”

On this study of 1,068 prostate cancer patients from 244 sites in 17 countries, Freedland and fellow investigators tested two experimental interventions-;one to deal with each of those issues.

Within the randomized clinical trial, one-third of the patients received ADT plus a medicine called enzalutamide, which blocks the results of testosterone. Enzalutamide keeps any testosterone remaining within the blood from stimulating the expansion of cancer cells.

One other third of the patients received enzalutamide alone. This feature relied on the medication to dam the results of testosterone regardless that testosterone levels within the patients’ blood weren’t reduced.

“We desired to see whether enzalutamide by itself was so effective that we didn’t need the ADT,” Freedland said.

The ultimate group of patients received ADT alone, which is the present standard treatment.

Investigators found that the mixture of ADT plus enzalutamide reduced the chance of metastasis or death by 58% over ADT alone. They found that enzalutamide alone reduced the chance of metastasis or death by 37% over ADT alone. Each treatments maintained quality of life relative to the ADT alone.

“While the mixture therapy offers greater risk reduction, some men might prefer enzalutamide alone. It does a very good job of stopping cancer spread or death, with different uncomfortable side effects that could be more acceptable for some men,” Freedland said.

The subsequent step is for the makers of enzalutamide to use for FDA approval, so the experimental therapy can come into wide use, Freedland said.

“Optimizing therapy for patients with aggressive reoccurrence after their prostate cancer is initially treated has been an unmet need,” said Dan Theodorescu, MD, PhD, director of Cedars-Sinai Cancer and the PHASE ONE Distinguished Chair. “The outcomes of this trial point the technique to two options which the study showed were more practical than current standard of care, giving these patients and their providers the chance to decide on a potentially improved course of therapy that best meets their needs.”