Call your doctor before leaving home if you think you’ve been exposed to COVID-19 or have symptoms

Due to the presence of COVID-19 in our community, visitor restrictions are in place for all Duke clinics and hospitals. For your safety and the safety of others, we recommend patients do not bring a visitor to Duke clinics, if at all possible. If a visitor must accompany a patient, only one individual over 12 years of age is allowed. Patients and visitors will be screened for symptoms upon arrival. Individuals with flu-like symptoms are not allowed. View the complete list of Visitor Restrictions.

Effective immediately, Duke Health is prioritizing and rescheduling some non-emergent or non-critical surgeries, procedures, and appointments. Check our COVID-19 (Coronavirus) page for updates.

Merck 3475 (Stomach and Esophagus Cancer) - Clinical Trial

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 the 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

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
Medical Oncologist
Protocol Number
IRB: PRO00100448
NCT: NCT03615326
Phase III
Contact the Duke Recruitment Innovation Center