FDA Approves Datroway as First TROP2-Directed ADC for First-Line Metastatic Triple-Negative Breast Cancer in Non-PD-1/PD-L1 Candidates

The US Food and Drug Administration has approved Datroway, developed by AstraZeneca and Daiichi Sankyo, as the first TROP2-directed antibody drug conjugate cleared for first-line treatment of metastatic triple-negative breast cancer in patients who are not suitable candidates for PD-1 or PD-L1 inhibitor therapy. This approval marks a significant shift in how this difficult-to-treat cancer may be managed going forward.

What is Datroway and Why Does This Approval Matter?

Datroway, known generically as datopotamab deruxtecan (datopotamab deruxtecan), is the first and only TROP2-directed antibody drug conjugate to demonstrate a significant improvement in overall survival compared to standard chemotherapy in the first-line metastatic triple-negative breast cancer setting. With a median overall survival approaching two years in clinical testing, this approval represents a meaningful advance over existing treatment options in a population with historically poor outcomes.

What Did the FDA Base This Approval On?

The FDA granted Priority Review to Datroway and based its approval on data from the TROPION-Breast02 Phase III clinical trial. This was a head-to-head comparison of Datroway against physician-choice chemotherapy in patients with metastatic triple-negative breast cancer who were not eligible for immunotherapy with PD-1 or PD-L1 inhibitors.

What Were the Key Results from TROPION-Breast02?

The trial produced results across multiple efficacy measures:

• Datroway reduced the risk of disease progression or death by 43 percent compared to chemotherapy.

• Median overall survival reached 23.7 months with Datroway versus 18.7 months with chemotherapy, a statistically significant improvement of 5.0 months

• Objective response rate was 64 percent with Datroway compared to 30 percent with chemotherapy.

• Median progression-free survival was 10.8 months with Datroway versus 5.6 months with chemotherapy.

These results collectively position Datroway as a potential new standard of care in this patient population.

What is Triple-Negative Breast Cancer and Who Does It Affect?

Triple-negative breast cancer represents roughly 15 percent of all breast cancer diagnoses worldwide, translating to an estimated 345,000 new cases globally each year. In the United States alone, between 32,000 and 48,000 cases were diagnosed in 2025, with approximately 11,000 patients receiving treatment in the first-line metastatic setting annually.

TNBC disproportionately affects younger women, premenopausal women, and women of Black and Hispanic descent. The metastatic form carries one of the worst prognoses among all breast cancer subtypes, with a median overall survival of just 12 to 18 months under standard treatment and a five-year survival rate of only around 15 percent.

How Does Datroway Work?

Datroway is an antibody drug conjugate built on Daiichi Sankyo's proprietary DXd ADC Technology platform.

It consists of three core components working together:

• A humanised anti-TROP2 IgG1 monoclonal antibody that targets TROP2, a protein highly expressed on cancer cells, developed in collaboration with Sapporo Medical University.

• A topoisomerase I inhibitor payload, specifically an exatecan derivative known as DXd, which delivers cytotoxic activity directly to tumor cells.

• Tetrapeptide-based cleavable linkers that connect the antibody to the payload and allow for controlled drug release within the tumor microenvironment.

This targeted design aims to maximize cancer cell destruction while limiting exposure of healthy tissue to the cytotoxic agent.