Ongoing Trial: The INDICATE trial is testing ways to personalize treatment for men with prostate cancer that returns after surgery

Last year, the ECOG-ACRIN Cancer Research Group (ECOG-ACRIN) published an entire issue of this advocacy blog featuring cancer clinical trials in which researchers are studying ways to reduce the intensity of treatment without sacrificing its effectiveness. This approach, called de-escalation (or optimization), is one way that doctors might tailor cancer treatment to individuals, rather than using a one-size-fits-all approach. However, de-escalation is not the only way to tailor treatment. Another method is to increase therapy, but only in patients where there is proven benefit—without exposing ALL patients to more toxicity. The INDICATE (EA8191) clinical trial is exploring this latter approach for prostate cancer.

To be eligible for this study, patients must have prostate cancer that has returned after surgery, as indicated by a rise in the blood level of prostate-specific antigen (PSA). PSA is a protein found in the blood that is typically elevated in men with prostate cancer. Patients must also have no evidence of cancer outside the pelvis by conventional imaging (e.g., CT or MRI).

The INDICATE trial will assess if the use of PET/CT scans can help identify patients for whom more therapy may lead to better outcomes. The standard treatment for prostate cancer that comes back after surgery is radiation to the prostate area and pelvic lymph nodes, plus six months of androgen deprivation therapy (ADT).

“Treatment approaches for patients with prostate cancer that comes back after surgery are rapidly evolving, thanks in large part to advances in molecular imaging,” said lead researcher Neha Vapiwala, MD. “We want to prove that this new technology actually benefits patients in a meaningful way. This study is designed to figure out if these new PET scans are helping us to more appropriately tailor patients’ therapy and improve their chances of a successful outcome.”

This study has four different treatment groups, and patients will be randomly assigned to a group depending on whether imaging shows that the cancer has spread outside the pelvis.

All participants will receive the standard-of-care treatment (see above). To explain:

• The first two groups are for those whose PET/CT scans did not show evidence of cancer outside of the pelvis. These patients will receive either the usual treatment or the usual treatment plus a drug called apalutamide. Apalutamide is an oral drug (taken by mouth) that prevents tumors from developing resistance to ADT. It is already approved by the FDA for patients with both metastatic and non-metastatic castration-resistant prostate cancer. The goal for this part of the study is to establish if the addition of apalutamide helps patients live longer before their cancer grows or causes additional major symptoms.
• The third and fourth groups are for those whose PET/CT scans did show evidence of cancer outside of the pelvis. The patients in this category will receive either the usual treatment plus apalutamide or the usual treatment plus apalutamide and additional radiation to the area(s) where the cancer has spread. The goal for this part of the study is to determine if additional radiation helps patients live longer before their cancer grows or causes additional major symptoms.

Doctors will follow patients in all four groups for up to ten years to watch for side effects, monitor the cancer, and measure outcomes.

This study is led by Neha Vapiwala, MD of the University of Pennsylvania/Abramson Cancer Center.

Learn more about the EA8191 study at ecog-acrin.org.