A Phase III Study of Trastuzumab Deruxtecan (DS-8201A) versus Standard Therapy for HER2-Low Inoperable or Metastatic Breast Cancer


Full Title

A phase 3, multicenter, randomized, open-label, active-controlled trial of trastuzumab deruxtecan (DS-8201a), an anti-HER2-antibody drug conjugate (ADC), versus treatment of physician’s choice for HER2-low, unresectable and/or metastatic breast cancer subjects


The purpose of this study is to compare the effectiveness of the drug trastuzumab deruxtecan with standard therapy in patients with inoperable or metastatic breast cancer that has low levels of the HER2 protein. Trastuzumab deruxtecan 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 breast cancer cells. Deruxtecan is the cell-killing part. When trastuzumab sticks to HER2, deruxtecan is released and kills the cancer cell from within. Trastuzumab deruxtecan is given intravenously (by vein).

Patients in this study will receive trastuzumab deruxtecan or one of five standard therapies (capecitabine, eribulin, gemcitabine, paclitaxel, or nab-paclitaxel).


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

  • Patients must have inoperable or metastatic breast cancer that has low levels of HER2 and continues to grow despite one or two prior regimens of chemotherapy for recurrent or advanced disease.
  • Patients need measurable disease and will need to have a biopsy.
  • Patients’ disease must have tested negative for HER2 earlier in the course of care, and patients may not have previously received HER2-targeted treatments.
  • 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 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 or older.

For more information and to inquire about eligibility for this study, please contact Dr. Shanu Modi at 646-888-5243.