AstraZeneca and Daiichi Sankyo’s HER2-targeting antibody drug conjugate (ADC) Enhertu (trastuzumab deruxtecan) has been granted a conditional approval in the EU.

The European Commission (EC) approval will make Enhertu available for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens.

The EC approval is based on results from the DESTINY-Breast01 Phase II trial, in which patients treated with Enhertu demonstrated a confirmed objective response rate of 61.4% after a median follow-up of 20.5 months.

This also included a 6.5% complete response rate, a 54.9% partial response rate and an estimated median duration of response (DoR) of 20.8 months for patients with HER2-positive metastatic breast cancer who had received at least two previous lines of therapy.

“Enhertu is already transforming outcomes for patients with HER2-positive metastatic breast cancer in the US and Japan, and this approval enables us to bring the benefits of this medicine to patients in the EU,” said Dave Fredrickson, executive vice president, Oncology Business Unit, AZ.

“We will continue to explore the potential of Enhertu in this setting, as well as in earlier lines of treatment and stages of disease, with the ambition of improving the lives of patients with HER2-targetable breast cancer,” he added.

In Europe, around 531,000 cases of breast cancer in women are diagnosed each year, with approximately one in five cases being HER2-positive.