Enhertu granted priority review by FDA in latest indication

Enhertu (trastuzumab deruxtecan) has been granted priority review in a new indication in the USA following results from the DESTINY-Breast04 Phase III trial showing that it is the first HER2-directed therapy to demonstrate a survival benefit in patients with HER2-low metastatic breast cancer.

The specifically engineered HER2-directed antibody drug conjugate being jointly developed and commercialized by AstraZeneca (LSE: AZN) and Daiichi Sankyo (TYO: 4568).

Both companies see this product as key to their oncology growth and the signs are that it could become one of the world's biggest-selling cancer drugs over the next decade. Some estimates predict that peak sales will exceed $4 million.

Susan Galbraith, executive vice president of AstraZeneca, said: “The data from DESTINY-Breast04 represent the first time a HER2-targeted therapy has shown a survival benefit in patients with HER2-low metastatic breast cancer. For more than two decades, only patients with HER2-positive breast cancer have been able to benefit from HER2-targeted therapies. If approved, Enhertu will redefine how we classify and treat metastatic breast cancer, enabling patients whose tumors have lower levels of HER2 expression the opportunity to benefit from a HER2-directed therapy.”

Enhertu is already approved is approved in more than 30 countries, including the the USA and the European Union (EU), for patients with previously treated HER2-positive metastatic breast cancer. Regulatory reviews for Enhertu in the HER2-low patient population are also underway in the EU and Japan.