This is a three-part, open-label, parallel-cohort study to assess the safety and tolerability of relugolix as the ADT component in combination treatment with abiraterone acetate plus a corticosteroid in patients with mCSPC or mCRPC (Part 1), apalutamide in patients with mCSPC or nmCRPC (Part 2), or docetaxel with or without prednisone in patients with mCSPC or mCRPC (Part 3).~The study will consist of a 45-day screening period followed by a 12-week treatment period with one of the three combination treatments (Parts 1, 2, or 3). All participants are required to have been treated with standard-of-care leuprolide acetate or a GnRH receptor antagonist (such as degarelix) in combination with either abiraterone plus prednisone. Participants will be transitioned from standard-of-care leuprolide acetate or the GnRH receptor antagonist to relugolix; with relugolix treatment initiated the day the next dose of leuprolide acetate or the GnRH antagonist is scheduled for administration with the prior dosing regimen of abiraterone acetate plus a corticosteroid, apalutamide, or docetaxel with or without prednisone being continued.~In addition to evaluating the safety and tolerability of relugolix, the study will also provide safety data as participants transition from injectable leuprolide acetate or degarelix to treatment with relugolix as the androgen-deprivation component of the treatment.
This study is being conducted to assess the safety and tolerability of relugolix with other agents approved for use in combination with androgen deprivation therapy (ADT) for a 12-week treatment period and an additional 40-week safety extension period in men with prostate cancer, either metastatic castration-sensitive prostate cancer (mCSPC) or non-metastatic or metastatic castration-resistant prostate cancer (nmCRPC or mCRPC).