Merck 3475 (Stomach and Esophagus Cancer)

What is the Purpose of this Study?

We are doing this study to compare the anti- tumor activitivy when the study drug, pembrolizumab, is given with trastuzumab and standard of care chemotherapy versus trastuzumab with placebo (an inactive pill) and chemotherapy.

We also want to test to see if it is safe, how well the drug combination works, and how your body handles the study drug if you do not receive the placebo.
What is the Condition Being Studied?
Stomach and Esophagus Cancer

Who Can Participate in this Study?

Adults who:

- Are at least 18 years of age

- Have confirmed diagnosis of previously untreated, locally advanced unresectable or metastatic HER2 positive gastric or gastroesophageal junction adenocarcinoma

Age Group
Participating Institutions

What is Involved?

If you choose to join this study, you will:

- Be randomly assigned (like a flip of a coin) to get either pembrolizumab (study drug) or placebo which is an inactive pill (along with trastuzumab and standard of care chemotherapy)

-- These will be given through an IV on Day 1 of each 3 week cycle

-- Depending on the side effects you may experience will decide how many cycles of the study drug you will get

- Have a study visit once every 3 weeks

-- During your clinic visits, blood samples and other procedures will be performed

- Have tests, exams, and procedures that are part of your standard care and for study purposes

Study Details

Full 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)
Principal Investigator

Gastrointestinal Oncology DCI Clinical Research Team
Protocol Number

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