Advancements in Nonmetastatic CRPC

Transcript: Judd Moul, MD: Thank you for joining this OncLive Peer Exchange® entitled, “Advances in the Treatment of Prostate Cancer.” There have been many strides made in recent years in treating both nonmetastatic and metastatic prostate cancer, yet challenges remain in selecting the optimal course of treatment for an individual patient. Today, I’m joined by a panel of experts in the field of prostate cancer research. Together, we will discuss the latest evidence surrounding the treatment of both nonmetastatic and metastatic disease and future trends with PARP [poly (ADP) ribose polymerase] inhibitors, and review data presented at the 2019 ASCO [American Society of Clinical Oncology] Annual Meeting.

I am Dr Judd Moul, professor of urologic surgery and anesthesiology at Duke University’s School of Medicine, and a member of the Duke Cancer Institute in Durham, North Carolina. Participating today on our panel are: .

Dr Tanya Dorff, an associate clinical professor in the Department of Medical Oncology and Therapeutics Research and head of the Genitourinary Cancers Program at City of Hope National Medical Center in Duarte, California.

Dr Alicia Morgans, an associate professor and medical oncologist at Northwestern’s Feinberg’s School of Medicine in Chicago, Illinois.

And Dr Neeraj Agarwal, professor of medicine and director of the Genitourinary Oncology Program at the Huntsman Cancer Institute in Salt Lake City, Utah.

Thank you, everyone, for joining us today. Let’s begin.

Our first discussion is going to be on nonmetastatic castration-resistant prostate cancer, which is something that’s been at the forefront of urology and medical oncology since February of 2018 when apalutamide was first FDA approved. I’d like to first ask Alicia to give us a little overview from a medical oncology perspective on nonmetastatic castration-resistant prostate cancer. Let’s focus first on the PROSPER trial.

Alicia Morgans, MD, MPH: Our world in medical oncology and urology was turned a little bit upside down when we all heard the data from the PROSPER and SPARTAN trials focusing on patients who had nonmetastatic castration-resistant prostate cancer at ASCO GI [American Society of Clinical Oncology Gastrointestinal Cancers Symposium] in 2018. One of the things that was most important about these trials—and I’ll focus on PROSPER specifically in just a second—is that both included patients who had a PSA [prostate-specific antigen] doubling time of less than or equal to 10 months. That selected a high-risk patient population with nonmetastatic castration-resistant disease.

The PROSPER study specifically enrolled patients who had a PSA doubling time of less than or equal to 10 months and a PSA that was greater than 2. It randomized them to treatment with ADT [androgen deprivation therapy], which they would just continue, because they had already been on that treatment, plus enzalutamide or placebo. They followed these patients for the development of metastasis, and they were looking for a primary endpoint of metastasis-free survival, which is also new and exciting to our field, because we had not previously had a regulatory endpoint that was built around something other than overall survival. This defined a new endpoint focused on a high-risk patient population, and prior to this, they had not had treatments directed at them. The PROSPER study looking at enzalutamide found that there was a prolongation in metastasis-free survival by about 22 months with the addition of enzalutamide to ADT as compared to placebo. It was a really exciting advance, and came simultaneously—at the same meeting—with apalutamide data from the SPARTAN trial.

Transcript Edited for Clarity