• Patient must have histologically confirmed adenocarcinoma of the prostate.

• Patient's primary prostate cancer tumor treated with surgery and/or radiation (+/- ADT).

• Patients must have one to three asymptomatic metastatic tumors of the bone or soft tissue that developed in the preceding 6 months that are \< 5cm or \< 250 cm3.

• Prostate-specific antigen (PSA) \> 0.5 ng/mL but \< 50ng/ml

• PSA doubling time (PSADT) \< 15 months (using all available PSA values from time of relapse)

• Testosterone \> 125 ng/mL

• Age ≥18 years.

• Patient must have life expectancy \> 12 months.

• Eastern Cooperative Oncology Group (ECOG) performance status 0-2

⁃ Normal organ and marrow function as defined below:

∙ leukocytes ≥3,000/mcL

‣ absolute neutrophil count ≥1,500/mcL

‣ platelets ≥100,000/mcL

‣ total bilirubin within normal institutional limits

‣ aspartate transaminase (AST)(serum glutamic-oxaloacetic transaminase (SGOT))/alanine transaminase (ALT)(serum glutamic-pyruvic transaminase (SGPT) ) ≤2.5 × institutional upper limit of normal creatinine, within normal institutional limits

⁃ Male participants with female partners of childbearing potential are required to use highly effective contraceptive measures which include condom use. A man is considered fertile after puberty unless permanently sterile by bilateral orchidectomy. A female partner of is considered a woman of childbearing potential (WOCBP) following menarche and until becoming postmenopausal unless permanently sterile.

∙ Permanent sterilization methods include hysterectomy, bilateral salpingectomy and bilateral oophorectomy.

‣ A postmenopausal state is defined as no menses for 12 months without an alternative medical cause. A high follicle-stimulating hormone (FSH) level in the postmenopausal range may be used to confirm a postmenopausal state in women not using hormonal contraception or hormonal replacement therapy. However, in the absence of 12 months of amenorrhea, a single FSH measurement is insufficient.

⁃ Highly effective contraceptive measures include:

‣ Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation: oral, intravaginal, transdermal

‣ Progestogen only hormonal contraception associated with inhibition of ovulation: oral, injectable, implantable

‣ Intrauterine device

‣ Intrauterine hormone-releasing system

‣ Surgical sterilization

‣ The male participant is vasectomized (with documented medical confirmation of surgical success) and is the sole sexual partner of the WOCBP participant

‣ Female partner of the male participant has undergone bilateral tubal ligation

‣ Complete sexual abstinence defined as refraining from heterosexual intercourse during the entire period of risk associated with study treatment. The reliability of sexual abstinence needs to be evaluated in relation to the duration of the clinical trial and the preferred and usual lifestyle of the participant.

⁃ Male participants should refrain from donating sperm for 180 days after the last dose of the study drugs.

⁃ Patient must have the ability to understand and the willingness to sign written informed consent.