A Phase III Study Comparing Trastuzumab Plus Chemotherapy and Pembrolizumab Immunotherapy with Trastuzumab Plus Chemotherapy and Placebo as Initial Treatment for HER2-Positive Advanced Gastric or Gastroesophageal Junction Cancer


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) (WIRB)


Chemotherapy drugs such as 5-fluorouracil (5-FU), cisplatin, oxaliplatin, and capecitabine are used to treat cancers of the stomach (gastric cancer) and the junction between the stomach and esophagus (gastroesophageal junction or GEJ cancers). Patients whose tumors make a protein called HER2 may also receive the drug trastuzumab. In this study, researchers want to see if adding the immunotherapy drug pembrolizumab to trastuzumab and chemotherapy is more effective as initial treatment for newly diagnosed advanced gastric and GE cancers than trastuzumab and chemotherapy alone.

Pembrolizumab blocks PD-1, a protein cancer cells use to evade detection by the immune system, thereby enabling the immune system to find and kill cancer cells. Patients in this study will be randomly assigned to receive trastuzumab, chemotherapy, and pembrolizumab or trastuzumab, chemotherapy, and a placebo (inactive drug). The chemotherapy for each patient will either be cisplatin/5-FU or capecitabine/oxaliplatin. Capecitabine is taken orally (by mouth) and the other medications are given intravenously (by vein).


To be eligible for this study, patients must meet several criteria, including but not limited to the following:

  • Patients must have previously untreated inoperable or metastatic gastric or GEJ cancer that is positive for HER2.
  • Patients may not have previously received immunotherapy.
  • Patients must be physically well enough that they are fully ambulatory, capable of all self care, and are capable of all but physically strenuous activities. As an example, patients must be well enough that they would be able to carry out office work or light housework.
  • This study is for patients age 18 and older.

For more information about this study and to inquire about eligibility, please contact Dr. Yelena Janjigian at 646-888-4186.





Disease Status

Relapsed or Refractory