Pembrolizumab + Trastuzumab + Chemotherapy for Gastric Cancer

Palo Alto (17 mi)

Age: 18+

Sex: Any

Travel: May be covered

Time Reimbursement: Varies

Trial Phase: Phase 3

Waitlist Available

Sponsor: Merck Sharp & Dohme LLC

No Placebo Group

Pivotal Trial (Near Approval)

Prior Safety Data

Breakthrough Therapy

Trial Summary

What is the purpose of this trial?The study will compare the efficacy and safety of pembrolizumab plus trastuzumab in combination with standard of care (SOC) chemotherapy versus trastuzumab in combination with SOC chemotherapy in participants with HER2-positive gastric cancer. The primary hypotheses of the study are that pembrolizumab plus trastuzumab in combination with chemotherapy is superior to trastuzumab plus chemotherapy in terms of 1) progression free survival (PFS) per Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1) as assessed by blinded independent central review (BICR), and 2) overall survival (OS).

Eligibility Criteria

This trial is for adults with untreated advanced HER2+ gastric or GEJ adenocarcinoma. Participants must have measurable disease, be in good physical condition (ECOG 0-1), and expect to live more than 6 months. They should have proper organ function and agree to use contraception. Exclusions include recent radiotherapy, other active cancers within 5 years, autoimmune diseases treated in the past 2 years, infections needing systemic therapy, poorly controlled diarrhea, significant cardiac issues or hypersensitivities.

Inclusion Criteria

My cancer is advanced stomach or GEJ cancer that has not been treated and is HER2 positive.

I am fully active or restricted in physically strenuous activity but can do light work.

My cancer is HER2-positive, confirmed by specific tests on my tumor.

Exclusion Criteria

I have received treatment for advanced stomach cancer that cannot be surgically removed.

I have another cancer that has gotten worse or needed treatment in the last 5 years.

I have mild to severe nerve damage.

I have been diagnosed with HIV.

I frequently have severe diarrhea that is hard to control.

I am currently being treated for an infection.

I am a woman of childbearing potential and my recent pregnancy test was negative.

I have a history of Hepatitis B or active Hepatitis C.

I have a heart condition that affects my daily life.

I have been treated for an autoimmune disease in the last 2 years.

I have an active tuberculosis infection.

I have received an organ or tissue transplant from another person.

I have been treated with specific immune therapy for cancer.

I have had pneumonitis treated with steroids or have it now.

I have an immune system disorder or am on long-term steroids.

I have undergone radiotherapy in the last 14 days.

I haven't had major surgery or serious injury in the last 28 days and don't expect to need major surgery while on the study treatment.

I have cancer that has spread to my brain or spinal cord.

Treatment Details

The study tests if pembrolizumab plus trastuzumab with standard chemotherapy works better for HER2+ gastric cancer than just trastuzumab with chemotherapy. It measures how long patients live without their cancer getting worse (PFS) and overall survival (OS). Patients are randomly assigned to receive either the new combination of drugs or the current standard treatment.

2Treatment groups

Experimental Treatment

Active Control

Group I: Pembrolizumab +Trastuzumab + ChemotherapyExperimental Treatment7 Interventions

Participants receive 200 mg pembrolizumab IV every 3 weeks (Q3W) plus trastuzumab (8 mg/kg loading dose, 6 mg/kg maintenance thereafter) IV Q3W in combination with FP or CAPOX chemotherapy (Global Cohort) or SOX chemotherapy (Japan cohort).

Group II: Placebo +Trastuzumab + ChemotherapyActive Control7 Interventions

Participants receive matched placebo to pembrolizumab IV Q3W plus trastuzumab (8mg/kg loading dose, 6mg/kg maintenance thereafter) IV Q3W in combination with FP or CAPOX chemotherapy (Global Cohort) or SOX chemotherapy (Japan cohort).

5-FU is already approved in United States, European Union, Canada, Japan for the following indications:

🇺🇸 Approved in United States as Fluorouracil for: