By Fineline Cube 
Partners AstraZeneca (NASDAQ: AZN) and Daiichi Sankyo (TYO: 4568) announced that they have received approval from the European Commission (EC) for an additional indication for Enhertu (trastuzumab deruxtecan). The HER2-targeted antibody-drug conjugate (ADC) is now approved for the treatment of adult patients with unresectable or metastatic hormone receptor (HR)-positive, HER2-low or HER2-ultralow breast cancer. This approval applies to patients who have received at least one endocrine therapy in the metastatic setting and are not considered suitable for endocrine therapy as the next line of treatment.
Mechanism and Approval
Enhertu is designed to deliver cytotoxic chemotherapy directly to cancer cells that express HER2, leveraging its mechanism to enhance therapeutic efficacy while minimizing systemic exposure. The latest approval expands Enhertu’s use to earlier-line treatment of HR+/HER2-low breast cancer and includes patients with HER2-ultralow disease, further broadening its patient population.
Clinical Trial Success
The approval is based on positive results from the Phase III DESTINY-Breast06 study, which demonstrated that Enhertu significantly reduced the risk of disease progression or death by 38% compared to chemotherapy. Patients treated with Enhertu achieved a median progression-free survival (mPFS) of 13.2 months versus 8.1 months for those receiving chemotherapy.
Global Impact
Enhertu is now approved in over 75 countries for the treatment of HER2-positive breast cancer, non-small cell lung cancer (NSCLC), gastric or gastroesophageal junction adenocarcinoma (GC/GEJC), and other solid tumors. This latest approval underscores the drug’s growing role in oncology care, offering new hope to patients with challenging treatment profiles.-Fineline Info & Tech