FDA Grants Priority Review to Datroway for Metastatic Triple-Negative Breast Cancer

The U.S. Food and Drug Administration (FDA) has accepted a supplemental biologics license application and granted priority review for Datroway (datopotamab deruxtecan) for the treatment of adult patients in the United States with unresectable or metastatic triple-negative breast cancer who are not candidates for PD-1/PD-L1 inhibitor therapy, AstraZeneca announced in a news release.

The application seeks approval for patients whose cancer is not eligible for immunotherapy, a group that currently relies on chemotherapy as the only approved first-line treatment option. This regulatory milestone, announced following the 2025 European Society for Medical Oncology Congress, moves the therapy toward a potential action date during the second quarter of 2026.

Priority review is reserved for medicines that the FDA believes could offer significant improvements over available treatments by enhancing safety or efficacy, preventing serious conditions or improving how well patients can follow their treatment plans. The application is also being reviewed under Project Orbis, an international framework that allows health authorities in multiple countries to review oncology medicines concurrently. This initiative is designed to deliver effective cancer treatments to patients as early as possible.

Main data supporting the findings

Triple-negative breast cancer (TNBC) is an aggressive form of the disease that tests negative for estrogen receptors, progesterone receptors and the overexpression of HER2. Because it lacks these common receptors, it is characteristically difficult to treat. While immunotherapy combined with chemotherapy has improved outcomes for some, approximately 70% of patients with metastatic TNBC are not candidates for immunotherapy. This includes patients whose tumors do not express PD-L1 and those who cannot receive the treatment due to other medical factors.

Data from the Phase 3 TROPION-Breast02 trial indicate that Datroway significantly improved survival outcomes compared to traditional chemotherapy. Patients treated with Datroway experienced a statistically significant five-month improvement in median overall survival.

Furthermore, the treatment nearly doubled the time patients lived without the disease worsening. Researchers reported a 43% reduction in the risk of disease progression or death compared to chemotherapy.

The trial also measured how well and how long patients responded to the treatment. Datroway demonstrated an objective response rate of 62.5% compared to 29.3% for those receiving chemotherapy. The duration of these responses was also longer for those in the Datroway group, lasting a median of 12.3 months compared to 7.1 months in the chemotherapy group.

Trial details

The TROPION-Breast02 trial was a global, multicenter, randomized, open-label Phase 3 study. It enrolled 644 patients across sites in Africa, Asia, Europe, North America and South America. The study specifically focused on patients with previously untreated locally recurrent inoperable or metastatic TNBC for whom immunotherapy was not an option.

The trial included a diverse group of participants, including those with de novo or recurrent disease and patients with poor prognostic factors such as stable brain metastases. Patients were eligible if they could not receive immunotherapy due to several reasons, such as prior exposure during early-stage disease, other existing health conditions or lack of access to immunotherapy in their geographic region.

During the study, participants were randomized to receive either Datroway or an investigator's choice of chemotherapy, which included paclitaxel, nab-paclitaxel, capecitabine, carboplatin or eribulin. Datroway is a TROP2-directed antibody drug conjugate (ADC). TROP2 is a protein broadly expressed in several solid tumors, including TNBC, and is associated with increased tumor progression and poor survival. The dual primary endpoints of the trial were progression-free survival, as assessed by a blinded independent central review, and overall survival.

Safety

In the TROPION-Breast02 trial, the safety profile of Datroway remained consistent with findings from previous clinical trials involving the medicine for the treatment of breast cancer.

Datroway is a specifically engineered TROP2-directed DXd antibody drug conjugate discovered by Daiichi Sankyo and jointly developed and commercialized by AstraZeneca and Daiichi Sankyo. The medicine is already approved in more than 40 countries for certain types of HR-positive, HER2-negative breast cancer and holds accelerated approval in the United States for a specific type of lung cancer. The ongoing monitoring of safety remains a core component of the regulatory review process as the FDA evaluates the supplemental application for this new patient population.

Reference

1. “Datroway granted Priority Review in the US as 1st-line treatment for patients with metastatic triple-negative breast cancer who are not candidates for immunotherapy,” news release; https://www.astrazeneca.com/media-centre/press-releases/2026/datroway-granted-priority-review-in-the-us-as-1st-line-treatment-for-patients.html

Editor's note: This article is for informational purposes only and is not a substitute for professional medical advice, as your own experience will be unique. Use this article to guide discussions with your oncologist. Content was generated with AI and reviewed by a human editor.

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.