De-Intensification and Intensification Clinical Trial Evaluation for Prostate Cancer (GUIDANCE)

Study Purpose

This phase III trial uses the Decipher risk score to guide therapy selection. Decipher score is based on the activity of 22 genes in prostate tumor and may predict how likely it is for recurrent prostate cancer to spread (metastasize) to other parts of the body. Decipher score in this study is used for patient selection and the two variations of treatment to be studied: intensification for higher Decipher score or de-intensification for low Decipher score. Patients with higher Decipher risk score will be assigned to the part of the study that compares the use of 6 months of the usual treatment (hormone therapy and radiation treatment) to the use of darolutamide plus the usual treatment (intensification). The purpose of this section of the study is to determine whether the additional drug can reduce the chance of cancer coming back and spreading in patients with higher Decipher score. The addition of darolutamide to the usual treatment may better control the cancer and prevent it from spreading. Alternatively, patients with low Decipher risk score will be assigned to the part of the study that compares the use of radiation treatment alone (de-intensification) to the usual approach (6 months of hormone therapy plus radiation). The purpose of this part of the study is to determine if radiation treatment alone is as effective compared to the usual treatment without affecting the chance of tumor coming back in patients with low Decipher score prostate cancer. Radiation therapy uses high energy to kill tumor cells and reduce the tumor size. Hormone therapy drugs such as darolutamide suppress or block the production or action of male hormones that play role in prostate cancer development. Effect of radiation treatment alone in patients with low Decipher score prostate cancer could be the same as the usual approach in stabilizing prostate cancer and preventing it from spreading, while avoiding the side effects associated with hormonal therapy.