This Study Will Explore Whether a Combination of the Investigational Drug Mevrometostat (PF-06821497) and Enzalutamide Will Work Better Than Taking Enzalutamide Alone in Participants With mCSPC Who Are ARPI naïve.

Launched by PFIZER · Jun 11, 2025

Keywords

ClinConnect Summary

This clinical trial is studying whether combining a new drug called mevrometostat with an existing prostate cancer medicine, enzalutamide, works better than using enzalutamide alone. The study focuses on men who have a type of prostate cancer that has spread to other parts of the body but still responds to hormone therapy (called metastatic castration-sensitive prostate cancer, or mCSPC). Importantly, participants should not have used certain hormone-blocking treatments before or received chemotherapy for their current cancer stage.

Men interested in joining the trial should be adults diagnosed with this type of prostate cancer, confirmed through scans or tests, and generally in good health with no serious heart problems or brain involvement. During the study, participants will receive either the combination of mevrometostat and enzalutamide or enzalutamide alone, and doctors will monitor how well the treatments work and watch for any side effects. This trial is not yet recruiting, and it aims to find better treatment options for men with this form of prostate cancer.

Gender

MALE

Eligibility criteria

• • Inclusion Criteria
• • Male participants aged ≥18 years (or the minimum age of consent in accordance with local regulations) at screening.
• • Histologically or cytologically confirmed adenocarcinoma of the prostate without small cell features.
• • Metastatic prostate cancer documented by positive bone scan (for bone disease) or metastatic lesion(s) on CT or MRI (for soft tissue/visceral disease).
• • Resolution of acute effects of any prior therapy to either baseline severity or CTCAE Grade ≤1 (except for AEs which do not constitute a safety risk in the investigator's judgement).
• • Participants must have ECOG PS 0 or 1.
• • Exclusion Criteria
• • Any medical 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.
• • Known or suspected brain metastasis or active leptomeningeal disease.
• • Participants must be treatment naïve at the mCSPC stage, eg, participants cannot have received any cytotoxic chemotherapy with the following exceptions: Treatment with first-generation antiandrogen (ADT) agents is allowed for mCSPC.
• • Previous administration with an investigational product (drug or vaccine) within 30 days.
• • Current use or anticipated need for drugs that are known strong CYP3A4/5 inhibitors and inducers (with exception of enzalutamide as part of this study).
• • Inadequate organ function.