Pembrolizumab + ADT for Prostate Cancer

Recruiting at212 trial locations

Age: 18+

Sex: Male

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Phase 3

Waitlist Available

Sponsor: Merck Sharp & Dohme Corp.

Pivotal Trial (Near Approval)

Prior Safety Data

Breakthrough Therapy

Trial Summary

What is the purpose of this trial?

This study will assess the efficacy and safety of pembrolizumab plus enzalutamide plus Androgen Deprivation Therapy (ADT) versus placebo plus enzalutamide plus ADT in participants with mHSPC. The primary hypothesis is that in participants with mHSPC, the combination of pembrolizumab plus enzalutamide plus ADT is superior to placebo plus enzalutamide plus ADT with respect to 1) radiographic progression-free survival (rPFS) per Prostate Cancer Working Group (PCWG)-modified Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 as assessed by blinded independent central review (BICR) and 2) overall survival (OS). As of 19-JAN-2023, the study was unblinded and all study participants stopped ongoing treatment with pembrolizumab/placebo and will continue to receive Standard of Care treatment until meeting protocol-specified discontinuation criteria if deriving clinical benefit. Safety analysis will be performed at the end of the study; there will be no further analyses for efficacy and electronic patient-reported outcome (ePRO) endpoints collected from participants beyond the IA1 cutoff date. All study participants will stop ongoing treatment with pembrolizumab/placebo. Exceptions may be requested for study participants who, in the assessment of their study physician, are benefitting from the combination of enzalutamide and pembrolizumab, after consulting with the Sponsor. All other study participants should be discontinued from study and be offered standard of care (SOC) treatment as deemed necessary by the Investigator. If enzalutamide as SOC is not accessible off study to the participant, central sourcing may continue. As of Amendment 04, disease progression will no longer be centrally verified, participants will only be assessed locally. As of Amendment 4, Second Course treatment is not an option for participants. There are currently no participants in the Second Course Phase.

Research Team

Medical Director

Principal Investigator

Merck Sharp & Dohme LLC

Eligibility Criteria

Men with advanced prostate cancer that has spread, who haven't had certain treatments like anti-PD-1 or anti-PD-L1 therapy. They must be able to perform daily activities with little help (ECOG status of 0 or 1), have good organ function, and agree to use contraception. Excluded are those with seizure history, vaccine within the last month, organ transplants, active autoimmune diseases needing recent treatment, significant heart issues or uncontrolled blood pressure.

Inclusion Criteria

I have a recent biopsy from a non-irradiated area or from a tumor in a previously radiated area.

I am willing to continue hormone therapy or have had both testicles removed.

My organs are functioning well.

Exclusion Criteria

I have an active HIV, HBV, or HCV infection.

I have been treated with advanced hormone therapy for cancer.

I have a history of seizures or conditions that could lead to seizures.

Treatment Details

Interventions

• Androgen Deprivation Therapy (ADT) (Procedure)
• Enzalutamide (Hormone Therapy)
• Pembrolizumab (Checkpoint Inhibitor)
• Placebo (Other)

Trial Overview The trial is testing if adding pembrolizumab to enzalutamide and ADT improves survival without cancer growth compared to placebo plus enzalutamide and ADT in men with metastatic hormone-sensitive prostate cancer. The study was blinded but now all participants will receive standard care after stopping pembrolizumab/placebo.

Participant Groups

Group I: Pembrolizumab + Enzalutamide + ADT Experimental Treatment 3 Interventions

Starting on Day 1 of each 21-day cycle, participants receive 200 mg pembrolizumab IV every 3 weeks (Q3W) for up to 35 cycles (approximately 2 years), plus 160 mg enzalutamide taken orally once daily, while maintaining continuous ADT with a luteinizing-hormone releasing hormone (LHRH) agonist or antagonist during study treatment. Participants will continue to receive enzalutamide and ADT until criteria for discontinuation are met.

Group II: Placebo + Enzalutamide + ADT Placebo Group 3 Interventions

Starting on Day 1 of each 21-day cycle, participants receive placebo IV Q3W for up to 35 cycles (approximately 2 years), plus 160 mg enzalutamide taken orally once daily, while maintaining continuous ADT with a LHRH agonist or antagonist during study treatment. Participants will continue to receive enzalutamide and ADT until criteria for discontinuation are met.

Androgen Deprivation Therapy (ADT) is already approved in Canada for the following indications:

Approved in Canada as Androgen Deprivation Therapy for:

• Prostate cancer
• Metastatic prostate cancer
• Non-metastatic high-risk prostate cancer

Who Is Running the Clinical Trial?

Merck Sharp & Dohme Corp.

Lead Sponsor

Trials

2,287

Recruited

4,582,000+

Chirfi Guindo

Merck Sharp & Dohme Corp.

Chief Medical Officer

Engineering degree from Ecole Centrale de Paris, MBA from New York University Stern School of Business

Robert M. Davis

Merck Sharp & Dohme Corp.

Chief Executive Officer since 2021

J.D. from Northwestern University Pritzker School of Law, MBA from Northwestern University Kellogg Graduate School of Management, Bachelor's in Finance from Miami University

Merck Sharp & Dohme LLC

Lead Sponsor

Trials

4,096

Recruited

5,232,000+

Chirfi Guindo

Merck Sharp & Dohme LLC

Chief Marketing Officer since 2022

Degree in Engineering from Ecole Centrale de Paris, MBA from New York University Stern School of Business

Robert M. Davis

Merck Sharp & Dohme LLC

Chief Executive Officer since 2021

JD from Northwestern University Pritzker School of Law, MBA from Northwestern University Kellogg Graduate School of Management, Bachelor's in Finance from Miami University