04:57 AM EST, 01/28/2025 (MT Newswires) -- AstraZeneca ( AZN ) and Daiichi Sankyo said their drug Enhertu has been approved in the US for the treatment of adult patients with certain types of inoperable breast cancer that has progressed on one or more endocrine therapies.

The drug, also known as fam-trastuzumab deruxtecan-nxki, has specifically been approved for use in patients with metastatic hormone receptor-positive, HER2-low, or HER2-ultralow types of breast cancer as determined by a US Food and Drug Administration-approved test, the companies said Monday.

The approval came after the drug secured Priority Review and Breakthrough Therapy Designation and was based on results from a phase 3 trial in which Enhertu showed a 36% reduction in the risk of disease progression or death in comparison with chemotherapy, the companies said.

The antibody drug conjugate was discovered by Daiichi Sankyo and is being jointly developed and commercialized by AstraZeneca ( AZN ) and Daiichi Sankyo, the companies said.