The European Medicines Agency (EMA) has officially commenced its review of ENHERTU® (trastuzumab deruxtecan) in combination with pertuzumab, a move that could soon establish the antibody-drug conjugate (ADC) as a primary treatment for HER2-positive metastatic breast cancer in the European Union.
The EMA’s validation of the Type II Variation application, announced Jan. 16, follows a landmark December 2025 approval by the U.S. Food and Drug Administration.
If authorized, the regimen would challenge the current standard of care—a combination of taxane, trastuzumab, and pertuzumab (THP)—which has remained the frontline clinical benchmark for more than ten years.
The submission is underpinned by results from the DESTINY-Breast09 Phase 3 trial.
Data presented at the 2025 ASCO Annual Meeting and published in The New England Journal of Medicine showed that the ENHERTU-pertuzumab combination reduced the risk of disease progression or death by 44% compared to THP.
Median progression-free survival (PFS) reached 40.7 months for the ENHERTU arm, compared to 26.9 months for the existing standard.
“This validation in the EU is an important step in moving us closer to offering ENHERTU in combination with pertuzumab as a potential new first-line treatment option,” said Ken Takeshita, MD, Global Head of R&D at Daiichi Sankyo.
ENHERTU, which has already transformed the treatment landscape for later-stage breast, lung, and gastric cancers, is the cornerstone of a multi-billion-dollar oncology alliance between AstraZeneca (NASDAQ:AZN) and Daiichi Sankyo.
The validation triggers a scientific review by the EMA’s Committee for Medicinal Products for Human Use (CHMP), with a decision expected within the next 210 days, excluding potential "clock stops" for additional data requests.