ADT Plus Abiraterone versus ADT Plus Docetaxel and Abiraterone in Treating Patients with Low Volume Metastatic Hormone Sensitive Prostate Cancer

Inclusion Criteria

• Patients must have histologically or cytologically confirmed prostate cancer (PCa) and imaging evidence of metastatic disease on CT, MRI, and/or bone scan. A prostate-specific membrane antigen (PSMA) positron emission tomography (PET) scan may be used, but findings confirming metastatic disease (ex. A lymph node > 1 cm or a bone lesion) must be observed on the CT portion of the scan
• Patients must have low volume metastatic disease per the Chemohormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer (CHAARTED) criteria; Low volume is defined as metastasis in lymph nodes outside of the pelvis and/or boney lesions (< 4 boney lesions, none outside of the axial skeleton). No visceral metastasis allowed. Metastatic disease must be documented either by a positive bone scan, contrast-enhanced abdominal/pelvic/chest computed tomography (CT) scan, magnetic resonance imaging scan or a prostate-specific membrane antigen (PSMA) PET scan. If a PSMA PET scan is used, the CT portion must confirm lymph node enlargement > 1cm or evidence of sclerosis for boney lesions. Metastatic disease is defined as either malignant lesions in the bone and/or measurable lymph nodes above the aortic bifurcation. Only patients with non-regional lymph node metastases (M1a) and/or bone metastases (M1B) will be eligible
• Patients must have measurable disease as determined per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 and Prostate Cancer Working Group 3 (PCWG3). Lymph nodes are measurable if the short axis diameter is ≥ 10mm
• Patient must be candidates for ADT, docetaxel and abiraterone therapy per treating investigator’s judgment
• Patients may have started ADT (luteinizing hormone-releasing hormone [LHRH] agonist/antagonist or orchiectomy) for ≤ 12 weeks before randomization, with or without first generation anti-androgen * NOTE: The first-generation anti-androgen must be stopped prior to randomization
• Patients must be age ≥ 18 years
• Patients must exhibit a/an Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 1
• Leukocytes (white blood cells [WBC]) ≥ 3,000/mcL
• Absolute neutrophil count (ANC) ≥ 1,500/mcL (cannot have received any growth factor within 4 weeks of enrollment)
• Hemoglobin (Hgb) ≥ 9 g/dL (cannot have received a packed red blood cell [pRBC] transfusion within 7 days of enrollment)
• Platelets (PLT) ≥ 100,000/mcL (cannot have received a platelet transfusion within 7 days of enrollment)
• Serum total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN)
• Aspartate transaminase (AST) (serum glutamic-oxaloacetic transaminase [SGOT]) ≤ 1.5 x institutional ULN
• Alanine transaminase (ALT) (serum glutamic-pyruvic transaminase [SGPT]) ≤ 1.5 x institutional ULN
• Serum creatinine ≤ 2 x institutional ULN OR creatinine clearance glomerular filtration rate (GFR) ≥ 50 mL/min/1.73 m^2 (may be measured or calculated. If calculated, for creatine clearance, use the Cockroft-Gault formula); estimated GFR (eGFR) is estimated GFR calculated by the abbreviated Modification of Diet in Renal Disease (MDRD) equation
• Patients with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial
• If a patient has known brain metastases, they must have received radiation per SOC to control disease to be eligible for this trial
• The effects of abiraterone and docetaxel on the developing human fetus are unknown. For this reason and because chemotherapy agents as well as other therapeutic agents used in this trial are known to be teratogenic: patients must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) nor donate sperm, from time of informed consent, for the duration of study participation, and for 3 months following completion of abiraterone and 6 months following completion of docetaxel therapy. Should a patient’s partner become pregnant or suspect they are pregnant while patient’s partner is participating in this study, patient’s partner should inform their treating physician immediately
• Patients must have the ability to understand and the willingness to sign a written informed consent document

Exclusion Criteria

• Prior treatment with: * LHRH agonist/antagonist started > than 12 weeks before randomization ** NOTE: Use of androgen deprivation therapy (ADT) prior to the diagnosis of metastatic disease is allowed * Second generation ARPIs such as enzalutamide, ARN-509, abiraterone, other investigational AR inhibitors * Cytochrome P17 enzyme inhibitors such as abiraterone acetate or oral ketoconazole as antineoplastic treatment for prostate cancer * Chemotherapy or immunotherapy for prostate cancer prior to randomization
• Treatment with radiotherapy (external beam radiation therapy, brachytherapy, or radiopharmaceuticals) within 2 weeks before randomization
• Previous (within 28 days before the start of study drug or 5 half–lives of the investigational treatment of the previous study, whichever is longer) or concomitant participation in another clinical study with investigational medicinal product(s)
• Known hypersensitivity to any of the study drugs, study drug classes or excipients in the formation of any of the study drugs
• Contraindication to both CT and MRI contrast agent
• Had any of the following within 6 months before randomization: stroke, myocardial infarction, severe/unstable angina pectoris, coronary/peripheral artery bypass graft, congestive heart failure (New York Heart Association class III or IV)
• Uncontrolled hypertension as indicated by a resting systolic blood pressure (BP) ≥ 160 mmHg or diastolic BP ≥ 100 mmHg despite medical management
• Patients who are unable to swallow oral medication, have malabsorption syndrome, have impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of study drug (e.g., ulcerative diseases, small bowel resection) or any other uncontrolled gastrointestinal condition (e.g., nausea, diarrhea, or vomiting) that might impair the oral bioavailability of any of the study drugs
• Patients with history of or evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated
• Patients with history of or evidence of chronic hepatitis C virus (HCV) infection, must have been treated and cured. For patients with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load
• Patients with a known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS) must have no detectable viral load on a stable antiviral regimen and have a CD4 count ≥ 200/mcL
• Patients with chronic liver disease with a need for treatment
• Prior systemic treatment with an azole drug (e.g., fluconazole, itraconazole) within 4 weeks of randomization
• Concomitant use of strong CYP3A4 inhibitors
• Patients who have an uncontrolled intercurrent illness including, but not limited to any of the following, are not eligible: * Ongoing or active infection requiring systemic treatment * Cardiac arrhythmia uncontrolled with medical management * Any other illness or condition or clinical laboratory finding that the treating investigator feels would interfere with study compliance or would compromise the patient’s safety or study endpoints * Major surgery within past 30 days * Psychiatric illness/social situations that would limit compliance with study requirements
• Patients who have not recovered from adverse events due to prior anti-cancer therapy (i.e., have residual toxicities > grade 1) with the exception of alopecia
• Patients who are receiving any other investigational agents
• Any other serious or unstable illness, or medical, social, or psychological condition, that could jeopardize the safety of the subject and/or his/her compliance with study procedures, or may interfere with the subject’s participation in the study or evaluation of the study results