What the trial was testing
The DESTINY-Breast04 enrolled 557 patients with breast cancer. The study was sponsored by Daiichi Sankyo and tracked outcomes across the full group of patients who matched the trial's eligibility profile.
It was a large trial designed to confirm whether the treatment works well enough for wider use. Trials at this stage are designed to produce evidence regulators and physicians can act on — not just observations to follow up later.
What the results showed
Roughly doubled the time before cancer progression in HER2-low breast cancer.
New England Journal of Medicine · 2022 · NCT03734029
These findings — that median time before cancer progression on trastuzumab deruxtecan vs. chemotherapy in HER2-low metastatic breast cancer — were published in the New England Journal of Medicine and represent the headline result of the study.
Researchers tracked outcomes across 557 patients enrolled in the trial. The result was consistent enough across the group that the team felt confident reporting it.
What this means for patients
For patients with breast cancer, this result changes the calculus on what to ask their care team about. Whether it changes day-to-day care depends on factors like disease subtype, prior treatments, and where the patient is in their care journey.
What you can do now
Trastuzumab deruxtecan (Enhertu) is FDA-approved for HER2-low metastatic breast cancer that has been previously treated with chemotherapy and available now. It is given as an IV infusion every three weeks. A serious lung side effect is a known risk and requires careful monitoring. Ask your oncologist about HER2-low testing and eligibility.
Eligibility for the treatments mentioned above depends on specific test results and clinical history. Bring this summary, the trial name, and your most recent labs or pathology report to your next visit.
Open breast cancer trials
Correlation of Clinical Response to Pathologic Response in Patients With Early Breast Cancer
The purpose of this study is to learn whether clinical response (the amount a tumor shrinks based on imaging or tumor measurements obtained by physical exam) predicts pathologic response (the amount of tumor remaining when surgery is performed) in participants with breast cancer who are receiving chemotherapy prior to surgery.
Real-life Evaluation of Endopredict® in Early HR+/HER2- Breast Cancer
EndoPredict is a genomic signature used to determine the 10-year risk of recurrence in early HR+/HER2- breast cancers classified as of intermediate risk according to conventional clinical and pathological criteria, and to guide the adjuvant treatment decision: hormone therapy alone or hormone therapy and chemotherapy. Since 2016, french laboratories performing the Endopredict test, included prospectively analyzed tumors in the SiMoSein registry with data collection : age, tumor size, lymph node status, histology, grade, HR and HER2 IHC status, Ki67, EPscore, Epclin score, risk of relapse, absolue benefit from chemotherapy, risk of late relapse The main objectives of the trial are to: Evaluate long-term relapse-free survival and overall survival over a 10-year period in breast cancer patients who underwent EndoPredict® testing according to: * EPclin risk class (low vs. high), * Lymph node status (N0/N1), * Tumor size (pT), * Age groups (\<40 years, 40-49 years, 50-69 years, ≥70 years), * EP score alone. This study provide real-life data to determine the clinical usefulness of this molecular signature in the management of early HR+/HER2- breast cancers. The ultimate goal is to be able to offer therapeutic de-escalation (avoiding chemotherapy) to patients who are reliably assessed as having a low risk of relapse.