ClinicalTrials.gov record
Completed Phase 3 Interventional Results available

Pembrolizumab/Placebo Plus Trastuzumab Plus Chemotherapy in Human Epidermal Growth Factor Receptor 2 Positive (HER2+) Advanced Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma (MK-3475-811/KEYNOTE-811)

ClinicalTrials.gov ID: NCT03615326

Public ClinicalTrials.gov record NCT03615326. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Apr 29, 2026, 9:39 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

A Phase III, Randomized, Double-blind Trial Comparing Trastuzumab Plus Chemotherapy and Pembrolizumab With Trastuzumab Plus Chemotherapy and Placebo as First-line Treatment in Participants With HER2 Positive Advanced Gastric or Gastroesophageal Junction Adenocarcinoma (KEYNOTE 811)

Study identification

NCT ID
NCT03615326
Recruitment status
Completed
Study type
Interventional
Phase
Phase 3
Lead sponsor
Merck Sharp & Dohme LLC
Industry
Enrollment
738 participants

Conditions and interventions

Interventions

  • 5-FU Drug
  • Capecitabine Drug
  • Cisplatin Drug
  • Oxaliplatin Drug
  • Pembrolizumab Biological
  • Placebo Biological
  • S-1 Drug
  • Trastuzumab Biological

Drug · Biological

Eligibility (public fields only)

Age range
18 Years and older
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Oct 4, 2018
Primary completion
Mar 19, 2024
Completion
Nov 11, 2025
Last update posted
Dec 10, 2025

2018 – 2025

United States locations

U.S. sites
23
U.S. states
16
U.S. cities
22
Facility City State ZIP Site status
UCLA Hematology/Oncology - Westwood (Building 200 Suite 120) ( Site 0045) Los Angeles California 90095
Pacific Cancer Care ( Site 0063) Monterey California 93940
UC Irvine Medical Center/Chao Family Comprehensive Cancer Center ( Site 0050) Orange California 92868
University of Miami Sylvester Comprehensive Cancer Center - Plantation ( Site 0026) Miami Florida 33136
Southeastern Regional Medical Center, Inc. ( Site 0058) Newnan Georgia 30265
Midwestern Regional Medical Center, Inc. ( Site 0059) Zion Illinois 60099
Beth Israel Deaconess Medical Center ( Site 0070) Boston Massachusetts 02215
Dana-Farber Cancer Institute [Boston, MA] ( Site 0010) Boston Massachusetts 02215
Minnesota Oncology Hematology, PA ( Site 8001) Minneapolis Minnesota 55404
Washington University School of Medicine ( Site 0040) St Louis Missouri 63110
Memorial Sloan Kettering Cancer Center- Monmouth ( Site 0071) Middletown New Jersey 07748
Memorial Sloan-Kettering Cancer Center at West Harrison ( Site 0065) Harrison New York 10604
Memorial Sloan-Kettering Cancer Center ( Site 0017) New York New York 10065
University of Rochester ( Site 0041) Rochester New York 14642
Levine Cancer Institute ( Site 0015) Charlotte North Carolina 28204
Duke Cancer Institute ( Site 0042) Durham North Carolina 27710
CTCA Southwestern ( Site 0060) Tulsa Oklahoma 74133
Cancer Treatment Centers of America-Eastern Regional Medical Center ( Site 0025) Philadelphia Pennsylvania 19124
Allegheny General Hospital ( Site 0053) Pittsburgh Pennsylvania 15212
Sanford Hematology Oncology-Sioux Falls SD ( Site 0004) Sioux Falls South Dakota 57104
University of Texas MD Anderson Cancer Center ( Site 0001) Houston Texas 77030
Oncology & Hematology Assoc. SW Virginia, Inc., DBA Blue Ridge Cancer Care ( Site 8000) Roanoke Virginia 24014
Seattle Cancer Care Alliance ( Site 0038) Seattle Washington 98109

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

Non-U.S. locations

This page focuses on the U.S. directory. The official record also lists 169 non-U.S. sites.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT03615326, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Dec 10, 2025 · Synced Apr 29, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT03615326 live on ClinicalTrials.gov.

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