Conditions: Prostate Cancer
Keywords: Bipolar Androgen Therapy Testosterone Enzalutamide Abiraterone Androgen Ablative Therapies
Allocation: NON_RANDOMIZED | Intervention model: SINGLE_GROUP
Enrollment: 112
Healthy volunteers: no

Brief summary:
Single-arm, single site, open label study of the effects of parenteral testosterone followed by enzalutamide, abiraterone or castration-only therapy in men with metastatic CRPC who previously progressed on one of these forms of therapy. The study will enroll four cohorts of patients: men with metastatic CRPC who have progressed on enzalutamide (Cohort A; n=30); men with metastatic CRPC who have progressed on abiraterone acetate (Cohort B; n=30); men with metastatic CRPC who have progressed on first line castration-only therapy (Cohort C; n=30); men with metastatic CRPC with inactivating somatic or germline mutations in ≥2 of the genes TP53, PTEN, or RB1 (Cohort D; n=20).

Detailed description:
The trial will enroll up to 110 patients, 30 for each Cohorts A-C and 20 for Cohort D. Eligible patients will continue on androgen ablative therapy with LHRH agonist (i.e. Zoladex, Trelstar, Eligard or Lupron) if not surgically castrated to suppress endogenous testosterone production. Patients will also receive intramuscular injection with either testosterone cypionate or testosterone enanthate at a dose of 400 mg every 28 days. This dosing scheme was designed to produce rapidly fluctuating serum testosterone levels from the supraphysiologic to the near-castrate range (i.e. Bipolar Androgen Therapy \[BAT\]). Assessments for response to testosterone will be made approximately every 3 months. Upon displaying evidence of progression, patients will then go on to receive either abiraterone (Cohort B) or enzalutamide (Cohort A), whichever agent they had previously progressed on prior to study enrollment. Patients in Cohort C will remain on LHRH agonist therapy and receive no additional androgen ablative hormonal therapy while those in the mutation-positive Cohort D will receive enzalutamide regardless of prior therapy.

Arms:
arm 1: Men with castration-resistant prostate cancer who have progressed on enzalutamide will be enrolled to this cohort. These patients will then receive intramuscular injections with testosterone cypionate 400 mg every 28 days or testosterone enanthate 400 mg every 28 days. Upon progression on testosterone cypionate or enanthate, men will be retreated with enzalutamide 160 mg by mouth daily. arm 2: Men with castration-resistant prostate cancer who have progressed on abiraterone will be enrolled to this cohort. These patients will then receive intramuscular injections with testosterone cypionate 400 mg every 28 days or testosterone enanthate 400 mg every 28 days. Upon progression on testosterone cypionate or enanthate, men will be retreated with abiraterone 1000 mg by mouth daily. arm 3: Men with metastatic prostate cancer who have only received first line hormone therapy with LHRH agonist alone or LHRH agonist plus an anti-androgen. Patients who have developed castrate resistance to first line therapy and have then received second line hormone therapy of any kind (including flutamide, bicalutamide, nilutamide, ketoconazole, abiraterone, enzalutamide, ARN-509 and investigational anti-androgens) are not eligible for enrollment in this cohort. arm 4: Men with metastatic prostate cancer who have castrate resistant prostate cancer with inactivating somatic or germline mutations in the genes TP53, RB1 or PTEN identified using clinical grade sequencing of tumor tissue performed by qualified laboratory. Patients must have mutations in ≥2 of these genes to be eligible. Eligible patients must have progressed on first line hormone therapy with LHRH agonist alone and must have received at least one but not more than two second generation androgen ablative therapy (i.e. Abiraterone, Enzalutamide or Apalutamide).

Interventions: intervention 1: Testosterone cypionate intervention 2: Testosterone Enanthate intervention 3: Abiraterone acetate intervention 4: Enzalutamide
Intervention descriptions: intervention 1: DEPO-Testosterone Injection, for intramuscular injection, contains testosterone cypionate which is the oil-soluble of the androgenic hormone testosterone. Testosterone cypionate is a white or creamy white crystalline powder, odorless or nearly so and stable in air. DEPO-Testosterone Injection is available in two strengths, 100 mg/mL and 200 mg/mL testosterone cypionate and will be administered at 400mg IM every 28 days. intervention 2: Testosterone Enanthate Injection, for intramuscular injection, contains testosterone enanthate which is the oil-soluble ester of the androgenic hormone testosterone. Enanthate Injection is available as a colorless to pale yellow solution. Each mL contains 200 mg testosterone enanthate in sesame oil with 5 mg chlorobutanol as a preservative. Will be administered at 400mg IM every 28 days. intervention 3: Abiraterone is an inhibitor of CYP17 (17α-hydroxylase/C17,20-lyase). Each ZYTIGA tablet contains 250 mg of abiraterone acetate. intervention 4: XTANDI is provided as liquid-filled soft gelatin capsules for oral administration. Each capsule contains 40 mg of enzalutamide as a solution in caprylocaproyl polyoxylglycerides.

Protocol document:
Prot_SAP_000.pdf: 
 
 
 
 
A Phase II Study to Determine Sequential Response to Bipolar Androgen Therapy 
(BAT) followed by Enzalutamide or Abiraterone Post-BAT in Men with Prostate 
Cancer Progressing on Combined Androgen Ablative Therapies. 
 
 
NCT number: NCT02090114 
 
 
 
 
Protocol Version 11 
July 2, 2020