AstraZeneca, Daiichi Sankyo Seek Regulatory Approvals for Enhertu in Early Breast Cancer

The US Food and Drug Administration on Monday accepted and granted priority review to AstraZeneca and Daiichi Sankyo's application seeking approval for Enhertu (trastuzumab deruxtecan) as post-neoadjuvant treatment for patients with HER2-positive early-stage breast cancer. The European Medicines Agency has validated the companies' Type II Variation marketing authorization application for the same indication.

The application seeks approval for Enhertu as a monotherapy for adult patients with HER2 positive breast cancer who have residual invasive disease after neoadjuvant HER2 targeted treatment. The validation confirms completion of the application and begins the scientific review process by the EMA's Committee for Medicinal Products for Human Use.

The application is based on data from the DESTINY-Breast05 phase 3 trial, which showed Enhertu reduced the risk of invasive disease recurrence or death by 53% compared to trastuzumab emtansine (T-DM1) in patients with HER2 positive breast cancer with residual invasive disease following neoadjuvant therapy. The trial results were presented at the 2025 European Society for Medical Oncology Congress and published in The New England Journal of Medicine.

DESTINY-Breast05 enrolled 1,635 patients across Asia, Europe, North America, Oceania and South America. The trial evaluated Enhertu at 5.4 mg/kg versus T-DM1 in patients with high risk of recurrence, defined as presentation with inoperable cancer prior to neoadjuvant therapy or pathologically positive axillary lymph nodes following neoadjuvant therapy.

Enhertu is a HER2 directed antibody drug conjugate developed using Daiichi Sankyo's proprietary DXd technology. The drug is currently approved in more than 90 countries for various HER2 positive cancer indications, including breast, lung, and gastric cancers.