Study of Hormone Therapy With or Without Niraparib After Radiation in High-Risk Localized or Locally Advanced Prostate Cancer

What this Trial Is About

Researchers are evaluating androgen ablation therapy with or without the drug niraparib after radiation treatment in men with high-risk localized or locally advanced prostate cancer. This phase II trial focuses on patients whose cancer has either not spread beyond the prostate or has spread only to nearby tissue or lymph nodes. The study aims to determine how adding niraparib to standard hormone therapies impacts disease control and survival outcomes, especially in patients with specific biomarker profiles and tissue responses to prior hormone treatment. Participants undergo a multi-phase treatment plan starting with a neoadjuvant phase where they receive apalutamide and androgen deprivation therapy ADT orally for up to three 28-day cycles. This is followed by a radiation phase combined with continued apalutamide and ADT for an additional three 28-day cycles. In the final adjuvant phase, patients with a favorable response continue on apalutamide plus ADT alone, while those with an unfavorable response are randomly assigned to receive either apalutamide plus ADT or a combination of abiraterone acetate, prednisone, ADT, and niraparib, each given orally for up to 12 cycles of 28 days. Treatments continue unless disease progression or unacceptable side effects occur. During the study, participants will have biopsies and blood samples collected for detailed analysis. They will be monitored for disease progression through radiographic and biochemical tests, with primary outcomes measured over three years from randomization. Safety and tolerability, overall survival, and progression-free survival including maintenance of non-castrate testosterone levels are also assessed. After completing the treatment, participants receive follow-up visits within 14 days, between 30 and 90 days, and then every three months for three years to monitor long-term outcomes.

Androgen Ablation Therapy With or Without Niraparib After Radiation Therapy for the Treatment of High-Risk Localized or Locally Advanced Prostate Cancer