A Study of Niraparib Combination Therapies for the Treatment of Metastatic Castration-Resistant Prostate Cancer

Other illness

• History or current diagnosis of myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML)
• Active malignancies (that is, progressing or requiring treatment change in the last 24 months) other than the disease being treated under study. The only allowed exceptions are: non-muscle invasive bladder cancer; skin cancer (non-melanoma or melanoma); breast cancer; malignancy that is considered cured with minimal risk of recurrence
• Active infection requiring systemic therapy
• Allergies, hypersensitivity, or intolerance to niraparib or the corresponding excipients
  • Combination 3:
• Prior disease progression during combination treatment with AA and poly (adenosine diphosphate \[ADP\]-ribose) polymerase inhibitor (PARPi). Prior discontinuation of treatment with AA or PARPi due to AA- or PARPi-related toxicity

Other

• Symptomatic brain metastases

• Diagnosed with mCRPC, who in the opinion of the investigator may benefit from treatment in Combination 3 of this study
• Able to continue gonadotropin releasing hormone analogue (GnRHa) therapy during the study if not surgically castrate (that is, subjects who has not undergone bilateral orchiectomy).
• Eastern Cooperative Oncology Group Performance Status (ECOG PS) of less than or equal to (\<=) 1
• Toxicity associated with prior chemotherapy or radiotherapy has resolved to Grade \<= 1 (except alopecia or Grade \<= 2 neuropathy) at screening
• Participant must agree not to donate sperm while on study treatment, and for 3 months following the last dose of study treatment