Join Us


Save as Favorite
Sign in to receive recommendations (Learn more)

Phase: Phase III ID number: NCT04622319

Sponsors of the trial: Daiichi Sankyo, Inc., and AstraZeneca

Who is the trial for?

The DESTINY-Breast05 trial is for people diagnosed with HER2-positive breast cancer that did not have a pathological complete response from treatment given before surgery. Doctors call treatments given before surgery neoadjuvant treatments.

One way doctors judge the effectiveness of neoadjuvant treatments is to look at the tissue removed during surgery to see if any actively growing cancer cells are present. If no active cancer cells are present, doctors call it a “pathologic complete response” or pCR.

Why the trial is being done

People diagnosed with HER2-positive breast cancer who do not have pCR after neoadjuvant treatment have a higher risk of recurrence (the breast cancer coming back).

The trial is looking to see whether fam-trastuzumab-deruxtecan-nxki reduces recurrence risk more than Kadcyla (chemical name: T-DM1 or ado-trastuzumab emtansine) when given after surgery for HER2-positive breast cancer that didn’t have pCR.

Under the brand name Enhertu, fam-trastuzumab-deruxtecan-nxki is approved in the United States to treat unresectable or metastatic HER2-positive breast cancer that has been treated with two or more anti-HER2 treatment regimens. Unresectable means the cancer that can’t be removed with surgery.

The DESTINY-Breast05 trial is using the medicine to treat a different stage of breast cancer than Enhertu is approved for, so when talking about the trial, the medicine is called by its chemical name: fam-trastuzumab-deruxtecan-nxki.

Fam-trastuzumab-deruxtecan-nxki is an antibody-drug conjugate made up of three parts:

  • fam-trastuzumab: an anti-HER2 antibody medicine that has the same basic structure as Herceptin (chemical name: trastuzumab)
  • a topoisomerase I inhibitor chemotherapy medicine called DXd; topoisomerase I inhibitors work by interfering with the cancer cells’ ability to replicate
  • a compound that links the fam-trastuzumab to the topoisomerase I inhibitor

Fam-trastuzumab-deruxtecan-nxki was designed to deliver the chemotherapy medicine to cancer cells in a targeted way by targeting the HER2 receptors on cancer cells.

Fam-trastuzumab-deruxtecan-nxki is given by intravenous infusion, which means the medicine is delivered directly into your bloodstream through an IV or a port. The medicine is usually given once every 3 weeks.

Specific eligibility requirements

People are eligible for the DESTINY-Breast05 trial if:

  • they are a legal adult in their country and have been diagnosed with HER2-positive breast cancer
  • the cancer has been treated before surgery with neoadjuvant chemotherapy and an anti-HER2 medicine
  • the cancer has not achieved pCR

People are not eligible for the DESTINY-Breast05 trial if they:

  • have been diagnosed with metastatic/stage IV breast cancer
  • have a previous history of breast cancer
  • have previously been treated with Kadcyla, Enhertu, or another anti-HER2 antibody-drug conjugate
  • history of interstitial lung disease, disorders that cause inflammation and scarring in the lungs
  • are pregnant or plan to become pregnant: women in the trial who are able to become pregnant should use effective birth control during the trial and for at least 7 months after the trial ends; men in the trial with partners who are able to become pregnant should use effective birth control during the trial and for at least 4 months after the trial ends

Potential side effects of the treatment being studied

In earlier studies, the most common side effects of fam-trastuzumab-deruxtecan-nxki were:

  • nausea
  • anemia
  • fatigue
  • low white blood cell counts
  • vomiting
  • diarrhea
  • hair loss
  • cough
  • constipation
  • low platelet counts
  • decreased appetite
  • liver problems
  • low levels of blood potassium

Fam-trastuzumab-deruxtecan-nxki also may cause serious side effects, including:

  • Interstitial lung disease: Interstitial lung disease is a general term for disorders that cause inflammation and scarring in the lungs. The scarring makes lung tissue stiff, which makes it difficult to breathe. You will be closely monitored for signs of interstitial lung disease while being treated with fam-trastuzumab-deruxtecan-nxki. You must tell your doctor right away if you experience shortness of breath or have a dry cough.
  • Heart problems: Fam-trastuzumab-deruxtecan-nxki may cause serious heart problems, including some that don’t have symptoms, such as reduced heart function, and some that do have symptoms, such as congestive heart failure. Symptoms to watch for include swelling of the ankles or legs, shortness of breath, cough, or weight gain of more than 5 pounds in less than 24 hours.
  • Neutropenia: Neutrophils are a type of white blood cell. Neutropenia means you have low levels of neutrophils in your blood. When neutropenia is severe, even the normal bacteria in your mouth and digestive tract can cause serious illness.

Your doctor will monitor you for any serious side effects while you’re being treated with fam-trastuzumab-deruxtecan-nxki and may reduce your dose, delay your treatment, or completely stop treatment if you do have serious side effects.

Study locations

The DESTINY-Breast05 trial is being conducted at multiple sites in the United States and around the world. For a complete list of sites, visit

For more information or to enroll

Email or call 908-992-6400.

Was this article helpful? Yes / No
Rn icon

Can we help guide you?

Create a profile for better recommendations

How does this work? Learn more
Are these recommendations helpful? Take a quick survey

Fy22oct sidebarad v02
Back to Top