Enhertu Shows Significant Efficacy in First-Line HER2-Positive Metastatic Breast Cancer Treatment

AstraZeneca and Daiichi Sankyo announced on April 21, 2025, that Enhertu (fam-trastuzumab deruxtecan-nxki) plus pertuzumab demonstrated a "highly statistically significant and clinically meaningful improvement in progression-free survival" as a first-line treatment for HER2-positive metastatic breast cancer15.
The interim analysis results from a Phase 3 clinical trial showed Enhertu's superiority compared to the current triple-drug combination standard for first-line treatment of this cancer type5.
Enhertu is an antibody drug conjugate (ADC) specifically engineered to target HER2, a protein overexpressed in certain breast cancers3.
The drug is already approved in more than 75 countries as a second-line treatment for HER2-positive breast cancer patients1.
In January 2025, Enhertu received FDA approval as the first HER2-directed therapy for patients with HER2-low or HER2-ultralow metastatic breast cancer following disease progression34.
In previous trials (DESTINY-Breast06), Enhertu demonstrated a 36% reduction in the risk of disease progression or death versus chemotherapy, with a median progression-free survival of 13.2 months compared to 8.1 months with chemotherapy3.
The new first-line data is particularly significant because many patients with metastatic breast cancer do not live long enough to receive a second line of treatment5.
Enhertu was originally discovered by Daiichi Sankyo and is being jointly developed and commercialized by Daiichi Sankyo and AstraZeneca3.

Sources:

1. https://www.astrazeneca-us.com/media/press-releases/2025/ENHERTU-fam-trastuzumab-deruxtecan-nxki-plus-pertuzumab-demonstrated-highly-statistically-significant-and-clinically-meaningful-improvement-in-progression-free-survival-THP-as-1st-line-therapy-for-patients-with-HER2-positive-metastatic-breast-cancer.html

3. https://daiichisankyo.us/press-releases/-/article/enhertu-approved-in-the-u-s-as-first-her2-directed-therapy-for-patients-with-her2-low-or-her2-ultralow-metastatic-breast-cancer-following-disease-prog

4. https://www.astrazeneca.com/media-centre/press-releases/2025/enhertu-approved-in-us-for-breast-cancer-post-et.html

5. https://medcitynews.com/2025/04/astrazeneca-daiichi-sankyo-enhertu-first-line-breast-cancer-adc-azn/