Early US approval for breast cancer drug Enhertu

With yet another earlier-than-expected US regulatory approval, on Friday, the US Food and Drug Administration granted accelerated approval to Enhertu (fam-trastuzumab deruxtecan-nxki) for the treatment of adults with unresectable (unable to be removed with surgery) or metastatic (when cancer cells spread to other parts of the body) HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens in the metastatic setting.

An FDA decision on the Biologic License Application has not been expected until second-quarter 2020. The drug is predicted peak annual sales of more than $4.5 billion and, according to UBS Securities Japan analyst Atsushi Seki, even $7 billion.

Developed by Daiichi Sankyo (TYO: 46568), whose shares gained 2.84% to 7,244 yen by close of trading today, and partner AstraZeneca (LSE: AZN), Enhertu, which combines the active ingredient in Roche's (ROG: SIX) top-selling Herceptin (trastuzumab) with a toxic payload designed to destroy tumor cells, is a human epidermal growth factor receptor 2 (HER2)-directed antibody and topoisomerase inhibitor conjugate, meaning that the drug targets the changes in HER2 that help the cancer grow, divide and spread, and is linked to a topoisomerase inhibitor, which is a chemical compound that is toxic to cancer cells.

Enhertu represents the newest treatment option