Trial purpose

Researchers are looking for other ways to treat breast cancer (BC) that is hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2-) and either unresectable locally advanced or metastatic.

* HR positive (HR+) means the cancer cells have proteins that attach to estrogen or progesterone (hormones) which help the cancer to grow and spread
* HER2 negative (HER2-) means the cancer cells have a low amount of a protein called HER2
* Unresectable locally advanced means the cancer cannot be completely removed by surgery and has spread into nearby tissue or muscles
* Metastatic means the cancer has spread to other parts of the body

Treatment for this type of breast cancer usually includes endocrine therapy (ET) and sometimes a second treatment. The main goal of this study is to learn if people who receive patritumab deruxtecan (also known as HER3-DXd and MK-1022) live longer overall or without the cancer growing/spreading, compared to people who receive chemotherapy or a different drug called trastuzumab deruxtecan.

View full trial information on Clinicaltrials.gov

NATIONAL TRIAL REFERENCE NUMBER

NCT07060807

When you talk with your doctor or clinical trial team member, please have the national trial reference number available.

Resources

Eligibility

Only a qualified healthcare professional can determine if you are eligible to take part in a clinical trial. However, this information may be useful in starting a conversation with your doctor.

Conditions

Breast Neoplasms

Age Range

18+

Sex

All

About the trial

Current trial phase

Phase 3

Tests the medicine or vaccine in approximately 1,000 to 5,000 participants. For medicines, participants have the disease or condition the medicine is designed to treat. In vaccine trials, the participants may be healthy or have diseases or conditions. Phase 3 trials may happen in a doctor’s office, a clinic, or a hospital.

Trial start and end dates
  • Trial start date 07-21-2025
  • Estimated primary completion date 07-14-2033
  • Estimated trial completion date 07-14-2033

Trial locations

Locations shown may have changed in some cases. Please call the number listed in the location results to confirm the nearest trial site. Talk with a trial site member for more information.

What can you do next?

If you think this clinical trial might be a good fit and you are interested in taking part, take the next step to see if you are eligible.

Discuss with your doctor or care team

Print this page with details about the trial or email it to your doctor to discuss the clinical trial during your next visit.

Get help talking with your doctor or care team

NATIONAL TRIAL REFERENCE NUMBER

NCT07060807

When you talk with your doctor or clinical trial team member, please have the national trial reference number available.