Study of Pembrolizumab (MK-3475) Plus Chemotherapy Versus Placebo Plus Chemotherapy in Participants With Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma (MK-3475-585/KEYNOTE-585)
Public ClinicalTrials.gov record NCT03221426. 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.
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, Clinical Trial of Pembrolizumab (MK-3475) Plus Chemotherapy (XP or FP) Versus Placebo Plus Chemotherapy (XP or FP) as Neoadjuvant/Adjuvant Treatment for Subjects With Gastric and Gastroesophageal Junction (GEJ) Adenocarcinoma (KEYNOTE-585)
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
The purpose of this study is to evaluate the efficacy of pembrolizumab (MK-3745) in the neoadjuvant (prior to surgery) or adjuvant (after surgery) treatment of previously untreated adults with gastric and gastroesophageal junction (GEJ) adenocarcinoma. The primary study hypotheses are that: * Neoadjuvant and adjuvant pembrolizumab plus chemotherapy, followed by adjuvant pembrolizumab is superior to neoadjuvant and adjuvant placebo plus chemotherapy, followed by adjuvant placebo in terms of Event-free Survival (EFS) based on Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1), and * Neoadjuvant pembrolizumab plus chemotherapy is superior to neoadjuvant placebo plus chemotherapy in terms of rate of Pathological Complete Response (pathCR) at the time of surgery. With Amendment 10, upon study completion, participants will be discontinued and may be enrolled in an extension study.
Study identification
- NCT ID
- NCT03221426
- Recruitment status
- Completed
- Study type
- Interventional
- Phase
- Phase 3
- Enrollment
- 1,007 participants
Conditions and interventions
Conditions
Interventions
- Pembrolizumab Biological
- Placebo Drug
- Cisplatin Drug
- Capecitabine Drug
- 5-fluorouracil Drug
- Docetaxel Drug
- Oxaliplatin Drug
- Leucovorin Drug
Biological · Drug
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 9, 2017 (Actual)
- Primary completion
- Feb 16, 2024 (Actual)
- Completion
- Apr 23, 2025 (Actual)
- Last update posted
- Mar 9, 2026
2017 – 2025
United States locations
- U.S. sites
- 14
- U.S. states
- 8
- U.S. cities
- 10
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 157 non-U.S. sites.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT03221426, 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 Mar 9, 2026 · Synced Oct 27, 2026
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Open the official record
The complete public registry record, listed eligibility criteria, and available contact information for NCT03221426 live on ClinicalTrials.gov.