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The safety and efficacy of this agent(s), or use in this setting, has not been established or is subject to confirmation. For an agent(s) whose safety and efficacy has not been established or confirmed, future regulatory approval or commercial availability is not guaranteed.
Active Not-enrolling
United States, Argentina, Australia, Belgium, Brazil, Canada, Chile, China, Czechia, Finland, France, Germany, Hungary, Israel, Italy, Japan, Korea, Republic of, New Zealand, Norway, Peru, Poland, Portugal, South Africa, Spain, Sweden, United Kingdom
for more information at clinicaltrials.gov
EXPERIMENTAL: Combination arm
Talazoparib plus enzalutamide
DRUG: Talazoparib with enzalutamide
Talazoparib 0.5 mg/day plus enzalutamide 160mg/day
ACTIVE_COMPARATOR: Monotherapy arm
Ezalutamide plus placebo
DRUG: Placebo with enzalutamide
Placebo plus enzalutamide 160 mg/day
Histologically or cytologically confirmed adenocarcinoma of the prostate without small cell or signet cell features
Asymptomatic or mildly symptomatic metastatic castration resistant prostate cancer (mCRPC) (score on BPI-SF Question #3 must be < 4).
For enrollment into Part 2 only (optional in Part 1): assessment of DDR mutation status
Consent to a saliva sample collection for a germline comparator unless prohibited by local regulations or ethics committee decision (optional for patients in Part 1).
Surgically or medically castrated, with serum testosterone ≤ 50 ng/dL (≤ 1.73 nmol/L) at screening.
Metastatic disease in bone documented on bone scan or in soft tissue documented on CT/MRI scan.
Progressive disease at study entry in the setting of medical or surgical castration as defined by 1 or more of the following 3 criteria:
Ongoing bisphosphonate or denosumab use prior to Day 1 (Part 1) or randomization (Part 2) is allowed but not mandatory.
Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1.
Life expectancy ≥ 12 months as assessed by the investigator.
Able to swallow the study drug and have no known intolerance to study drugs or excipients.
Must agree to use a condom when having sex with a partner from the time of the first dose of study drug through 4 months after last dose of study treatment. Must also agree for female partner of childbearing potential to use an additional highly effective form of contraception from the time of the first dose of study treatment through 4 months after last dose of study treatment when having sex with a non pregnant female partner of childbearing potential.
Must agree not to donate sperm from the first dose of study drug to 4 months after the last dose of study drug.
Evidence of a personally signed and dated informed consent document (and molecular prescreening consent if appropriate) indicating that the patient [or a legally acceptable representative/legal guardian] has been informed of all pertinent aspects of the study.
Willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures
Any prior systemic cancer treatment initiated in in the non metastatic CRPC and mCRPC disease state. Patients whose only evidence of metastasis is adenopathy below the aortic bifurcation. Prior treatment with second-generation androgen receptor inhibitors (enzalutamide, apalutamide, and darolutamide), a PARP inhibitor, cyclophosphamide, or mitoxantrone for prostate cancer. Prior treatment with platinum-based chemotherapy within 6 months (from the last dose) prior to Day 1 (Part 1) or randomization (Part 2), or any history of disease progression on platinum-based therapy within 6 months (from the last dose). Treatment with cytotoxic chemotherapy, biologic therapy including sipuleucel T, or radionuclide therapy received in the castration-sensitive prostate cancer is NOT exclusionary if discontinued in the 28 days prior to Day 1 (Part 1) or randomization (Part 2). Treatment with any investigational agent within 4 weeks before Day 1 (Part 1) or randomization (Part 2). Prior treatment with opioids for pain related to either primary prostate cancer or metastasis within 28 days prior to Day 1 (Part 1) or randomization (Part 2). Current use of potent P-gp inhibitors within 7 days prior to Day 1 (Part 1) or randomization (Part 2). Major surgery (as defined by the investigator) within 2 weeks before Day 1 (Part 1) or randomization (Part 2), or palliative localized radiation therapy within 3 weeks before randomization (Part 2). Clinically significant cardiovascular disease Significant renal dysfunction as defined by any of the following laboratory abnormalities: • Renal: eGFR \< 30 mL/min/1.73 m2 by the MDRD equation (available via www.mdrd.com). Patients enrolled in Part 1 only: Moderate renal impairment (eGFR 30-59 mL/min/1.73 m2) at screening. Significant hepatic dysfunction as defined by any of the following laboratory abnormalities on screening labs:
Absolute neutrophil count \< 1500/µL, platelets \< 100,000/µL, or hemoglobin \< 9 g/dL (may not have received growth factors or blood transfusions within 14 days before obtaining the hematology values at screening). Known or suspected brain metastasis or active leptomeningeal disease. Symptomatic or impending spinal cord compression or cauda equina syndrome. Any history of myelodysplastic syndrome, acute myeloid leukemia, or prior malignancy except any of the following:
Gastrointestinal disorder affecting absorption. Fertile male subjects who are unwilling or unable to use highly effective methods of contraception for the duration of the study and for 4 months after the last dose of investigational product. Investigator site staff members directly involved in the conduct of the study and their family members, site staff members otherwise supervised by the investigator, or patients who are Pfizer employees, including their family members, directly involved in the conduct of the study. Other acute or chronic medical (concurrent disease, infection, or comorbidity) or psychiatric condition including recent (within the past year) or active suicidal ideation or behavior or laboratory abnormality that interferes with ability to participate in the study, may increase the risk associated with study participation or investigational product administration, or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the patient inappropriate for entry into this study. History of seizure or any condition that may predispose to seizure (eg, prior cortical stroke, significant brain trauma). Also, history of loss of consciousness or transient ischemic attack within 12 months of randomization (Part 2).
Number of Participants With Treatment-Emergent Adverse Events (TEAEs) Occuring Within the First 66 Days of Dosing - Part 1
An adverse event (AE) was any untoward medical occurrence in a participant who received study intervention without regard to possibility of causal relationship. TEAEs are defined as newly occurring AEs or those worsening after first dose. As per Common Terminology Criteria for Adverse Events (CTCAE) version 4, Grade 1= mild AE; Grade 2= moderate AE; Grade 3= severe AE; Grade 4= life-threatening or disabling AE; Grade 5= death related to an AE. Serious TEAE (SAE) was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. SAEs were determined according to the investigator's assessment. Results as of 16 Aug 2022 are reported.
Post dose on Day 1 up to Day 66 in Part 1
Number of Participants With All-Causality Clustered Treatment-Emergent Cytopenias by Preferred Term (PT) and Max CTCAE Grade Occuring Within the First 66 Days of Dosing - Part 1
An AE was any untoward medical occurrence in a participant who received study intervention without regard to possibility of causal relationship. TEAEs are defined as newly occurring AEs or those worsening after first dose. As per CTCAE version 4, Grade 1=mild AE; Grade 2=moderate AE; Grade 3=severe AE; Grade 4=life-threatening or disabling AE; Grade 5=death related to an AE. Medical Dictionary for Regulatory Activities (MedDRA) v25.0 coding dictionary applied. PTs for the cluster terms are: ANEMIA, including Anemia, Hematocrit decreased, Hemoglobin decreased, and Red blood cell count decreased; THROMBOCYTOPENIA, including, Thrombocytopenia and Platelet count decreased; NEUTROPENIA, including Febrile neutropenia, Neutropenia and Neutrophil count decreased; LEUKOPENIA, including Leukopenia, White blood cell count decreased. Events in any grade with at least 1 occurrence in participants are reported for this outcome measure. Results as of 16 Aug 2022 are reported.
Post dose on Day 1 up to Day 66 in Part 1
Number of Participants With All-Causality TEAEs During the Overall Period of Part 1
An adverse event (AE) was any untoward medical occurrence in a participant who received study intervention without regard to possibility of causal relationship. TEAEs are defined as newly occurring AEs or those worsening after first dose. As per CTCAE version 4, Grade 1= mild AE; Grade 2= moderate AE; Grade 3= severe AE; Grade 4= life-threatening or disabling AE; Grade 5= death related to an AE. Serious TEAE (SAE) was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. SAEs were determined according to the investigator's assessment. Results as of 16 Aug 2022 are reported.
Post dose on Day 1 up to 28 days after the last dose of study intervention, or before new systemic antineoplastic therapy, whichever occurred first (maximum of 235.14 weeks)
Number of Participants With Treatment-Related TEAEs During the Overall Period of Part 1
An AE was any untoward medical occurrence in a participant who received study intervention without regard to possibility of causal relationship. TEAEs are defined as newly occurring AEs or those worsening after first dose. Treatment-related AE was any untoward medical occurrence attributed to study intervention in a participant who received study intervention. As per CTCAE version 4, Grade 1= mild AE; Grade 2= moderate AE; Grade 3= severe AE; Grade 4= life-threatening or disabling AE; Grade 5= death related to an AE. An SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. SAEs were determined according to the investigator's assessment. Results as of 16 Aug 2022 are reported.
Post dose on Day 1 up to 28 days after the last dose of study intervention, or before new systemic antineoplastic therapy, whichever occurred first (maximum of 235.14 weeks)
Number of Participants With All-Causality Clustered Treatment-Emergent Cytopenias by PT and Max CTCAE Grade Occuring Anytime After Dosing - Part 1
An AE was any untoward medical occurrence in a participant who received study intervention without regard to possibility of causal relationship. TEAEs are defined as newly occurring AEs or those worsening after first dose. As per CTCAE version 4, Grade 1=mild AE; Grade 2=moderate AE; Grade 3=severe AE; Grade 4=life-threatening or disabling AE; Grade 5=death related to an AE. MedDRA v25.0 coding dictionary applied. PTs for the cluster terms are: ANEMIA, including Anemia, Hematocrit decreased, Hemoglobin decreased, and Red blood cell count decreased; THROMBOCYTOPENIA, including, Thrombocytopenia and Platelet count decreased; NEUTROPENIA, including Febrile neutropenia, Neutropenia and Neutrophil count decreased; LEUKOPENIA, including Leukopenia, White blood cell count decreased. Events in any grade with at least 1 occurrence in participants are reported for this outcome measure. Results as of 16 Aug 2022 are reported.
Post dose on Day 1 up to 28 days after the last dose of study intervention, or before new systemic antineoplastic therapy, whichever occurred first (maximum of 235.14 weeks)
Number of Participants With Treatment-Related Clustered Treatment-Emergent Cytopenias by PT and Max CTCAE Grade in >=10% of Participants Occuring Anytime After Dosing - Part 1
An AE was any untoward medical occurrence in a participant who received study intervention without regard to possibility of causal relationship. TEAEs are newly occurring AEs or those worsening after first dose. Treatment-related AE was any AE attributed to study intervention in a participant who received study intervention. As per CTCAE version 4, Grade 1=mild; Grade 2=moderate; Grade 3=severe; Grade 4=life-threatening or disabling; Grade 5=death related to an AE. MedDRA v25.0 coding dictionary applied. PTs for the cluster terms are: ANEMIA, including Anemia, Hematocrit decreased, Hemoglobin decreased, and Red blood cell count decreased; THROMBOCYTOPENIA, including, Thrombocytopenia and Platelet count decreased; NEUTROPENIA, including Febrile neutropenia, Neutropenia and Neutrophil count decreased; LEUKOPENIA, including Leukopenia, White blood cell count decreased. Events in any grade with incidence in \>=10% of participants are reported. Results as of 16 Aug 2022 are reported.
Post dose on Day 1 up to 28 days after the last dose of study intervention, or before new systemic antineoplastic therapy, whichever occurred first (maximum of 235.14 weeks)
Blinded Independent Central Review (BICR) Assessed Radiographic Progression-Free Survival (rPFS) Per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 for All-Comers - Part 2 Cohort 1
rPFS is defined as the time from the date of randomization to first objective evidence of radiographic progression as assessed in soft tissue per RECIST 1.1, or death, whichever occurs first. Soft tissue disease status was assessed at regular intervals during the course of the study by computed tomography (CT) of chest and CT or magnetic resonance imaging (MRI) of abdomen and pelvis. Progression is defined using RECIST 1.1 as a \>=20% increase in the sum of the longest diameter of target lesions, or a measurable increase in a non-target lesion, or the appearance of new lesions. Results as of 16 Aug 2022 are reported for this outcome measure.
From the start of treatment to the time of first documented progression, or death (maximum up to 42 months)
BICR Assessed rPFS Per RECIST 1.1 in Patients With DDR Deficiencies - Part 2
rPFS is defined as the time from the date of randomization to first objective evidence of radiographic progression as assessed in soft tissue per RECIST 1.1, or death, whichever occurs first. Soft tissue disease status was assessed at regular intervals during the course of the study by CT of chest and CT or MRI of abdomen and pelvis. Results as of 03 Oct 2022 are reported for this outcome measure.
From the start of treatment to the time of first documented progression, or death (maximum up to 38 months)
1054
Sponsor: Pfizer
Collaborator: Astellas Pharma Inc
For more information, call or email the Pfizer Clinical Trial Contact Center:
When calling, please reference this study number: