AstraZeneca and Daiichi Sankyo's trastuzumab deruxtecan has taken a step closer to US approval having been accepted for priority review by the US Food and Drug Administration (FDA) for breast cancer.

The drug, an HER2-targeting antibody drug conjugate (ADC), has been filed as a treatment HER2-positive metastatic breast cancer. A decision by the regulator is expected for the second quarter of 2020.

“Trastuzumab deruxtecan has the potential to transform the treatment landscape for patients with HER2-positive metastatic breast cancer who have limited treatment options today,” said José Baselga, executive vice president, Oncology R&D at AstraZeneca.

“This priority review draws on the strength and the consistency of results seen in the Phase I and Phase II trials and is a critical step on the journey to deliver this potential new medicine to patients.”

The BLA is based on the combination of data from the Phase I trial published in The Lancet Oncology and the pivotal Phase II DESTINY-Breast01 trial. The response rate observed in DESTINY-Breast01, as assessed by an independent review committee, “validated the clinical activity observed in the Phase I trial,” AZ noted.

Detailed data from DESTINY-Breast01 are to be presented at the forthcoming San Antonio Breast Cancer Symposium in December.