AstraZeneca and Daiichi Sankyo’s Enhertu (trastuzumab deruxtecan) has been approved in the European Union (EU) as a monotherapy for the adjuvant treatment of adult patients with resected HER2-positive breast cancer who have residual invasive disease after neoadjuvant taxane-based and HER2-targeted treatment.

The approval by the European Commission (EC) follows the positive opinion of the Committee for Medicinal Products for Human (CHMP) use of the European Medicines Agency (EMA) and is based on results from the DESTINY-Breast05 phase 3 trial presented at the 2025 European Society for Medical Oncology (ESMO) congress and subsequently published in The New England Journal of Medicine.

Sibylle Loibl, MD, PhD, German Breast Group (GBG) and Goethe University Medicine Frankfurt, Frankfurt am Main, and lead investigator of the DESTINY-Breast05 trial, said, “For patients with HER2-positive early breast cancer and residual invasive disease after neoadjuvant therapy, reducing the risk of disease recurrence is critical for sustained long-term outcomes. The EU approval of trastuzumab deruxtecan, which demonstrated a more than 50 percent reduction in risk of recurrence compared to Standard of Care in DESTINY-Breast05, has the potential to change how we treat eligible patients in this setting.”

In DESTINY-Breast05, Enhertu significantly reduced the risk of invasive disease recurrence or death (Invasive Disease Free Survival [IDFS]) by 53 percent (based on a Hazard Ratio [HR] of 0.47; 95 percent Confidence Interval [CI] 0.34-0.66; p<0.0001) compared to trastuzumab emtansine (T-DM1) in patients with HER2-positive breast cancer with residual invasive disease following neoadjuvant therapy.

Dave Fredrickson, Executive Vice President, Oncology Haematology Business Unit, AstraZeneca, said, “The goal of treatment in early breast cancer is to help as many patients as possible achieve cure. Unfortunately, despite treatment advances, some patients still face recurrence in the long term. The approval of Enhertu in the adjuvant setting for patients with residual disease after neoadjuvant treatment has the potential to establish a new benchmark in this curative-intent setting, with more than 92 percent of patients alive and free of invasive disease at 3 years.”

The safety profile of Enhertu was consistent with the known profile with no new safety concerns identified.

Ken Keller, Global Head of Oncology Business, and President and CEO, Daiichi Sankyo, said, “By bringing Enhertu into the adjuvant setting, we are advancing this treatment option earlier in the course of disease for patients with HER2-positive early breast cancer. This first approval of Enhertu in early breast cancer in the EU reflects our continued commitment to bringing innovative medicines into earlier treatment settings, where there is significant potential to improve long-term outcomes for patients.”

Enhertu demonstrated a 3-year IDFS rate of 92.4 percent (95 percent CI 89.7-94.4) compared to 83.7 percent with T-DM1 (95 percent CI 80.2-86.7). It is now approved in over 35 countries for the adjuvant treatment of adult patients with HER2-positive breast cancer who have residual invasive disease following neoadjuvant trastuzumab (with or without pertuzumab) and taxane-based treatment based on the DESTINY-Breast05 trial.

Enhertu is a specifically engineered HER2-directed DXd Antibody Drug Conjugate (ADC) discovered by Daiichi Sankyo and being jointly developed and commercialised by AstraZeneca and Daiichi Sankyo.