A Phase IB/II Study of Trastuzumab Deruxtecan in People with Advanced Gastric Cancer or Gastroesophageal Junction Cancer


Full Title

A Phase 1b/2 Multicenter, Open-label, Dose-escalation and Dose-expansion Study to Evaluate the Safety, Tolerability, Pharmacokinetics, Immunogenicity, and Antitumor Activity of Trastuzumab Deruxtecan (T-DXd) Monotherapy and Combinations in Adult Participants with HER2-expressing Gastric Cancer (DESTINY-Gastric03)


Trastuzumab is an anticancer medication that targets HER2, a protein overproduced by some cancers of the stomach (gastric cancers) and the junction between the stomach and esophagus (gastro-esophageal junction or GEJ cancers). In this study, researchers are evaluating the safety of combining the drug trastuzumab deruxtecan (T-DXd) with immunotherapy and/or chemotherapy in patients with inoperable or metastatic stomach and GEJ cancers that have come back or continued to grow despite prior treatment.

T-DXd is an antibody drug conjugate (ADC). ADCs have two parts: the antibody targets cancer cells and the other part (a chemotherapy drug attached to the antibody) kills cancer cells. Trastuzumab, the antibody part, binds to HER2 on stomach and GEJ cancer cells. Deruxtecan is the cell-killing part. When trastuzumab sticks to HER2, deruxtecan is released and kills the cancer cell from within.

T-DXd is approved to treat metastatic breast cancer; its use in this study is investigational. It is given intravenously (by vein).

Who Can Join

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

  • Patients must have inoperable or metastatic gastric or GEJ cancers that are positive for the HER2 protein and came back or continued to grow despite at least two prior regimens of treatment.
  • Patients should recover from the serious side effects of previous treatments before entering the study.
  • Patients must be physically well enough that they are fully ambulatory, capable of all self-care, and 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.




Phase I/II (phases 1 and 2 combined)



ClinicalTrials.gov ID