FDA granted Priority Review to AstraZeneca’s supplemental application for Enhertu in early-stage HER2-positive breast cancer, moving the drug closer to a potential new indication for patients at high risk of recurrence following initial treatment.

The decision builds on FDA’s previous priority review approval back in October 2024, granting priority review to Enhertu for HER2-Low or HER2-Ultralow metastatic breast cancer. Enhertu currently has several approved indications, including the most recent approval of Enhertu plus Perjeta for HER2-positive metastatic breast cancer.²

AstraZeneca and Daiichi Sankyo submitted the supplemental Biologics License Application (BLA) for Enhertu (trastuzumab deruxtecan) to treat adult patients with HER2-positive breast cancer who have residual invasive disease after neoadjuvant HER2-targeted treatment.¹

The FDA's decision is expected to come in the third quarter of 2026, as the application is also being reviewed under Project Orbis, a framework for concurrent regulatory review among international partners.¹ Enhertu has separately received Breakthrough Therapy Designation from the FDA in this setting.¹

Why was Enhertu granted priority review?

The BLA for Enhertu was filed based on results from the Destiny-Breast05 Phase III trial, presented at the ESMO 2025 Congress and published in the New England Journal of Medicine.¹

The trial enrolled 1,635 patients across Asia, Europe, North America, Oceania, and South America, comparing Enhertu against trastuzumab emtansine (T-DM1) as a post-neoadjuvant treatment.²

In the trial, Enhertu displayed the ability to reduce the risk of invasive disease recurrence or death by 53% compared with T-DM1, with a three-year invasive disease-free survival rate of 92.4% versus 83.7%. The drug also reduced the risk of distant disease recurrence by 51% and the risk of brain metastases by 36% compared with T-DM1. Results were consistent across all pre-specified patient subgroups, and no new safety concerns were identified.²

Why does this decision matter for patients?

According to AstraZeneca, about one in five breast cancers are HER2-positive, a subtype associated with aggressive disease and poor prognosis.¹ Roughly half of patients diagnosed with HER2-positive early breast cancer will also have residual disease after neoadjuvant treatment, placing them at elevated risk of recurrence.

While the five-year survival rate for early-stage HER2-positive breast cancer is close to 90%, that figure drops to approximately 30% if the disease progresses to metastatic stage, making effective post-neoadjuvant treatment critical.¹

Susan Galbraith, executive vice president of oncology and haematology R&D at AstraZeneca, said the priority review brings the company closer to offering patients at higher risk of recurrence the opportunity for sustained long-term outcomes and a potential path to cure. “While there has been significant progress in treating HER2-positive early breast cancer, managing patients at a higher risk of recurrence remains challenging. With this Priority Review, we move closer to bringing Enhertu to the post-neoadjuvant setting, offering more patients the opportunity for sustained long-term outcomes and a potential path to cure.”

Ken Takeshita, global head of R&D at Daiichi Sankyo, said the data from Destiny-Breast05 reinforce Enhertu's potential to become a new standard of care in HER2-positive early breast cancer.

Enhertu is already approved in more than 90 countries for HER2-positive metastatic breast cancer. Regulatory submissions based on Destiny-Breast05 are also under review in the EU and Japan.¹

Sources

1. Enhertu granted Priority Review in the US as post-neoadjuvant treatment for patients with HER2-positive early breast cancer AstraZeneca March 9, 2026 https://www.astrazeneca.com/media-centre/press-releases/2026/enhertu-granted-priority-review-in-the-us-as-post-neoadjuvant-treatment-for-patients-with-her2-positive-early-breast-cancer.html
2. A Study of Trastuzumab Deruxtecan (T-DXd) Versus Trastuzumab Emtansine (T-DM1) in High-risk HER2-positive Participants With Residual Invasive Breast Cancer Following Neoadjuvant Therapy (DESTINY-Breast05) National Library of Medicine September 5, 2025 https://clinicaltrials.gov/study/NCT04622319
3. ENHERTU® Plus Pertuzumab Approved in the U.S. as First New Treatment in More Than a Decade for First-Line Treatment of Patients with HER2 Positive Metastatic Breast Cancer. News release. AstraZeneca. December 15, 2025. Accessed December 15, 2025. https://www.businesswire.com/news/home/20251210874349/en/ENHERTU-Plus-Pertuzumab-Approved-in-the-U.S.-as-First-New-Treatment-in-More-Than-a-Decade-for-First-Line-Treatment-of-Patients-with-HER2-Positive-Metastatic-Breast-Cancer