# Pembrolizumab (MK-3475) Plus Chemotherapy Versus Placebo Plus Chemotherapy in Participants Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma (MK-3475-859/KEYNOTE-859)

> **NCT03675737** · PHASE3 · COMPLETED · sponsor: **Merck Sharp & Dohme LLC** · enrollment: 1579 (actual)

## Conditions studied

- Stomach Neoplasms

## Interventions

- **BIOLOGICAL:** Pembrolizumab
- **DRUG:** Cisplatin
- **DRUG:** 5-fluorouracil
- **DRUG:** oxaliplatin
- **DRUG:** capecitabine
- **DRUG:** Placebo for Pembrolizumab

## Key facts

- **NCT ID:** NCT03675737
- **Lead sponsor:** Merck Sharp & Dohme LLC
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2018-11-08
- **Primary completion:** 2022-10-03
- **Final completion:** 2025-03-03
- **Target enrollment:** 1579 (ACTUAL)
- **Last updated:** 2026-02-27


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT03675737

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT03675737, "Pembrolizumab (MK-3475) Plus Chemotherapy Versus Placebo Plus Chemotherapy in Participants Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma (MK-3475-859/KEYNOTE-859)". Retrieved via AI Analytics 2026-06-08 from https://api.ai-analytics.org/clinical/NCT03675737. Licensed CC0.

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