Daiichi Sankyo Korea and AstraZeneca Korea receive approval for Enhertu for patients with HER2 low- and ultra-low-expression metastatic breast cancer treated with endocrine therapy

CAR-T Digest - August 2020

Weekly Digest - January 2026

21 January 2026: Daiichi Sankyo Korea and AstraZeneca Korea receive approval for Enhertu for patients with HER2 low- and ultra-low-expression metastatic breast cancer treated with endocrine therapy

Daiichi Sankyo Korea and AstraZeneca Korea announced that Enhertu (trastuzumab deruxtecan) has received approval from Korea’s Ministry of Food and Drug Safety for the treatment of patients with HER2 low- and ultra-low-expression metastatic breast cancer who have been treated with endocrine therapy, further expanding access to targeted treatment in this setting
With this decision, Enhertu is now approved as a first-line option after endocrine therapy for patients with hormone receptor–positive metastatic breast cancer, extending its use beyond HER2 low expression to also include HER2 ultra-low expression and enabling earlier use without prior chemotherapy
The expanded indication is supported by results from the Phase 3 DESTINY-Breast06 study, which demonstrated that Enhertu significantly reduced the risk of disease progression or death compared with chemotherapy and delivered a median progression-free survival exceeding one year in patients who had not previously received chemotherapy
In the intention-to-treat population, Enhertu showed superior efficacy across key endpoints, including progression-free survival, objective response rate, and clinical benefit rate, with consistent benefits observed in patients with both HER2 low and ultra-low expression and a safety profile aligned with previous studies
This approval addresses a major unmet need in hormone receptor–positive metastatic breast cancer, the most common breast cancer subtype, by offering a more effective targeted therapy option earlier in the treatment journey for patients who are no longer benefiting from endocrine therapy