AstraZeneca Plc (AZN) announced that its experimental drug datopotamab deruxtecan (Dato-DXd) did not achieve statistical significance in a Phase 3 trial for the treatment of inoperable or metastatic hormone receptor (HR)-positive, HER2-low or negative breast cancer. The study, known as TROPION-Breast01, compared Dato-DXd to an investigator’s choice of chemotherapy in patients who had previously received endocrine-based therapy and at least one systemic therapy. While the trial did not meet the primary endpoint of overall survival, it did meet the dual primary endpoint of progression-free survival, demonstrating that Dato-DXd can delay disease progression. The study also showed improvements in patient-reported outcomes, suggesting that the drug may offer a better quality of life for patients.
The safety profile of Dato-DXd remained consistent with previous findings. Notably, the rates of Grade 3 or higher treatment-related adverse events were lower than those seen with chemotherapy, and no new safety concerns were identified. The rates of all-grade interstitial lung disease (ILD) remained low, and no new Grade 3 or higher ILD events were observed. However, the trial results may have been affected by the fact that several antibody-drug conjugates (ADCs) were approved during the study period, including Enhertu (trastuzumab deruxtecan). Subsequent treatment following patients’ disease progression or treatment discontinuation could have influenced the overall survival results.
This news follows earlier positive results from AstraZeneca’s TROPION-Lung01 Phase 3 trial of Dato-DXd in treating locally advanced or metastatic nonsquamous non-small cell lung cancer (NSCLC). In that trial, while not statistically significant, overall survival results numerically favored Dato-DXd compared to docetaxel, the standard of care chemotherapy for this type of lung cancer.
In a separate development, the FDA approved AstraZeneca’s FluMist as the only self-administered influenza vaccine. This needle-free nasal spray is now approved for self-administration by adults up to 49 years of age or for parent/caregiver administration to individuals 2-17 years of age. Once available, individuals 18 and older will be able to have FluMist delivered directly to their homes via FluMist Home.
AZN stock closed down 1.86% at $76.92 during the premarket session on Monday, following the release of the TROPION-Breast01 trial results.
