A Study to Learn About the Investigational Medicine Called PF-06821497 (Mevrometostat) in Men With mCRPC Who Were Previously Treated With Abiraterone Acetate for Prostate Cancer (MEVPRO-1).

Pfizer

Status and phase: Not yet enrolling; Phase 3

Conditions: Metastatic Castrate Resistant Prostate Cancer (mCRPC)

Treatments: Drug: PF-06821497; Drug: Enzalutamide; Drug: Docetaxel

Study type: Interventional

Funder types: Industry

Identifiers

NCT06551324

C2321014

2024-511650-50-00 (Registry Identifier)

Details and patient eligibility

About

Pfizer MEVPRO-1 (C2321014) is a randomized, open-label, multi-center clinical trial evaluating whether combining the study medicine (PF-06821497) with enzalutamide is safe and effective compared to physician's choice of either second-line androgen receptor (AR) directed therapy with enzalutamide or docetaxel (chemotherapy) for treating metastatic castration-resistant prostate cancer (mCRPC) after progression on prior abiraterone acetate treatment.

The primary objective of this clinical trial is to assess the radiographic progression free survival (rPFS) of the combination of PF-06821497 plus enzalutamide versus physician's choice of enzalutamide or docetaxel.

Enrollment: 600 estimated patients

Sex: Male

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Histologically or cytologically confirmed adenocarcinoma of the prostate without small cell features.
• Metastatic disease in bone documented on bone scan, or in soft tissue documented on CT/MRI scan.
• Surgically or medically castrated, with serum testosterone ≤50 ng/dL (≤1.73 nmol/L) at screening.
• Progressive disease in the setting of surgical or medical castration. Note: Evidence of disease progression with at least 12 weeks of abiraterone acetate in the metastatic castrate sensitive prostate cancer (mCSPC) setting, or first line metastatic castrate resistant prostate cancer (mCRPC) setting is required.
• Eastern Cooperate Oncology Group (ECOG) performance status 0 - 2, with life expectancy of at least 6 months as assessed by the investigator.

Exclusion criteria

• Any medical (including active or clinically significant bacterial, fungal or viral infection) or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
• Clinically significant cardiovascular disease.
• Central nervous system (CNS) pathology/neurological findings including known or suspected brain metastasis or active leptomeningeal disease, symptomatic or impending spinal cord compression or cauda equina syndrome, or clinically significant history of seizure or any condition that may predispose to seizure.
• Prior treatment for prostate cancer at any stage with any cytotoxic chemotherapy, radioligand therapy, androgen receptor signaling inhibitors (ARSi) including enzalutamide, apalutamide, darolutamide, poly ADP-ribose polymerase (PARP) monotherapy or other systemic anti-cancer treatment (approved drugs or experimental compounds such as, antibody therapy, immunotherapy, gene therapy, angiogenesis inhibitors, EZH2 inhibitors).
• Inadequate renal function defined by an estimated glomerular filtration rate (eGFR) <45 mL/min.
• Hepatic dysfunction.
• Hematologic abnormalities

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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600 participants in 2 patient groups

Arm A

Experimental group

Description:

Investigational Arm A: PF-06821497 875 mg twice daily (BID) + enzalutamide 160 mg every day (QD)

Treatment:

Drug: Enzalutamide

Drug: PF-06821497

Arm B

Active Comparator group

Description:

Comparator Arm B: Physician's choice of enzalutamide 160 mg QD or docetaxel 75 mg/m2 intravenous (IV) every 21 days

Treatment:

Drug: Docetaxel

Drug: Enzalutamide