AZ, Daiichi get EU okay for breast cancer drug Datroway

AstraZeneca and Daiichi Sankyo have claimed approval from the European Commission for their TROP2-directed antibody-drug conjugate (ADC) for breast cancer, Datroway, the latest to emerge from their multibillion-dollar alliance.

Datroway (datopotamab deruxtecan) has been given the green light in the EU as a treatment for patients with metastatic HR-positive, HER2-negative breast cancer who have previously been treated with endocrine therapy and at least one line of chemotherapy.

It is the second ADC brought to market by AZ and Daiichi Sankyo after Enhertu (trastuzumab deruxtecan), a HER2-targeting ADC that is already a blockbuster with sales of more than $3.75 billion in 2024, up from $2.57 billion in the prior year. EU approval takes the tally of countries that have approved Datroway to more than 30, also including the US and Japan.

It is also the second TROP2-targeting ADC to reach the EU market after Gilead Sciences' Trodelvy (sacituzumab govitecan), which was approved for a similar HR-positive, HER2-negative breast cancer population in 2023 and can also be used to treat triple-negative breast cancer (TNBC).

There's another potential competitor on the way as well, as MSD is running late-stage trials of its sacituzumab tirumotecan candidate – licensed from Kelun – in several indications spanning breast, lung, and other solid tumours. The drug has already been approved in China for lung cancer.

The EU approval of Datroway is based on the results of the TROPION-Breast01 study, which revealed that patients treated with the ADC had a median progression-free survival (PFS) of 6.9 months compared to 4.9 months for those receiving chemotherapy, a 37% improvement.

"With the majority of breast cancer cases historically considered HR-positive, HER2-negative, additional treatment options are needed to improve outcomes for patients with metastatic disease that continues to progress following endocrine-based therapy and initial chemotherapy," commented Barbara Pistilli, who leads the breast cancer unit at the Gustave Roussy Cancer Centre in Villejuif, France.

"The approval of Datroway in the EU will provide these patients with a new treatment option that can help slow the progression of this disease," she added.

At one point, AZ and Daiichi Sankyo were also hoping to get EU approval for the TROP2 drug as a treatment for locally advanced or metastatic non-squamous non-small cell lung cancer (NSCLC) based on the TROPION-Lung01 study but withdrew the application in December after the EU regulator said it did not consider the evidence for that use to be sufficiently strong.

AstraZeneca has a target of $5 billion or more in peak annual sales for both Enhertu and Datroway, making the pair a core part of its objective of achieving $80 billion in group revenues by 2030.

Photo by National Cancer Institute on Unsplash