AstraZeneca and Daiichi Sankyo’s antibody‑drug conjugate Datroway (datopotamab deruxtecan) has been granted Priority Review by the U.S. Food and Drug Administration (FDA) for use as an initial treatment in adults with unresectable or metastatic triple‑negative breast cancer (TNBC) who are not eligible for PD‑1/PD‑L1 immunotherapy. The FDA’s decision signals that the therapy may offer a meaningful advance over existing options, with a regulatory verdict expected in the second quarter of 2026.
A Potential New Standard for a Hard‑to‑Treat Population
Roughly 70% of patients with metastatic TNBC cannot receive immunotherapy, either because their tumors lack PD‑L1 expression or due to other medical or geographic barriers. For these individuals, chemotherapy remains the only approved first‑line option—despite historically poor outcomes and limited durability of response. Datroway aims to change this landscape. Its submission is also being evaluated through Project Orbis, an initiative that enables simultaneous review of oncology medicines by multiple global regulatory agencies.
Compelling Phase III Results
The FDA review is supported by the Phase III TROPION‑Breast02 trial, which enrolled 644 patients worldwide. Datroway demonstrated notable improvements over standard chemotherapy, including:
- A five‑month increase in median overall survival
- A 43% reduction in the risk of disease progression or death
- More frequent and longer‑lasting tumor responses (Objective response rate 62.5% vs. 29.3% with chemotherapy)
Investigators noted that these benefits occurred even in a trial population that included patients with highly aggressive disease characteristics, including brain metastases that are stable, and recurrent early‑stage disease. Safety findings were consistent with previous Datroway studies in breast cancer, with no new concerns identified.
About TNBC and the Need for New Options
TNBC represents about 15% of breast cancer cases globally and disproportionately affects younger women, as well as Black and Hispanic patients. Its aggressive biology, lack of common hormone receptors, and limited targeted therapies contribute to a median overall survival of only 12 to 18 months for metastatic disease. TROP2, the protein targeted by Datroway, is widely expressed in TNBC and linked to poorer clinical outcomes, making it an important therapeutic target.
What Datroway Is
Datroway is a TROP2‑directed antibody‑drug conjugate that uses Daiichi Sankyo’s DXd technology to deliver a topoisomerase I inhibitor directly into tumor cells. It has been approved in multiple countries already for certain HR‑positive, HER2‑negative breast cancers, and holds accelerated approval in the U.S. for EGFR‑mutated non‑small cell lung cancer. Over 20 global trials are currently exploring Datroway across various tumor types.
Looking Ahead
If approved, Datroway would be the first therapy to demonstrate a survival advantage over chemotherapy in the first‑line setting for metastatic TNBC patients who are unable to receive immunotherapy—potentially establishing a new standard of care for this underserved population.
