Daiichi Sankyo and AstraZeneca (AZN, Financial) have announced that their joint supplementary Biologics License Application (sBLA) for the antibody-drug conjugate (ADC) Enhertu (trastuzumab deruxtecan) has been accepted by the U.S. FDA and granted priority review status. The drug is intended for adult patients with unresectable or metastatic HER2-low (IHC 1+ or IHC 2+/ISH-) or HER2 ultra-low (IHC 0 with membrane staining) expressing breast cancer who have undergone at least one line of metastatic endocrine therapy. The FDA is expected to complete its review in the first quarter of 2025.
If approved, Enhertu will be the first HER2-targeted ADC therapy to be used prior to chemotherapy in patients with metastatic breast cancer. Breast cancer remains one of the most common cancers and a leading cause of cancer-related deaths worldwide. HER2 is a tyrosine kinase receptor growth protein expressed on the surface of various tumor cells, including breast cancer. Approximately 60% to 65% of HR-positive, HER2-negative breast cancers have low HER2 expression, and another 25% show ultra-low HER2 expression. Currently, there are no approved targeted therapies for patients with ultra-low HER2 expression.
Enhertu, jointly developed by AstraZeneca and Daiichi Sankyo, is the first HER2-targeted ADC therapy with indications not limited to any specific type of cancer.
