Researchers have examined whether the antibody-drug conjugate fam-trastuzumab deruxtecan-nxki (T-DXd) may improve progression-free survival in patients with advanced breast cancer who have undergone prior hormone-based therapies, according to recent findings presented by Bardia et al at the 2024 San Antonio Breast Cancer Symposium (SABCS; Abstract LBA1-04) and simultaneously published in The New England Journal of Medicine.
Background
“The [SABCS] provides an invaluable platform to share and discuss major advancements that are reshaping breast cancer care,” explained lead study author Aditya Bardia, MD, MPH, FASCO, Professor of Medicine and Hematology/Oncology at the David Geffen School of Medicine and Director of the Breast Oncology Program and Translational Research Integration at the Health Jonsson Comprehensive Cancer Center at the University of California, Los Angeles. “This year’s presentations reflect the academic commitment to innovative research that aims to improve survival and quality of life for patients worldwide,” he emphasized.
Study Methods and Results
In this study, the researchers randomly assigned 866 patients with hormone receptor–positive, HER2-low or HER2-ultralow metastatic breast cancer who experienced disease progression following at least one endocrine therapy and no prior chemotherapy to receive either T-DXd or physician’s choice of chemotherapy.
The researchers previously reported that patients in the T-DXd group experienced an extended progression-free survival of 13.2 months compared with 8.1 months among those in the chemotherapy group.
The researchers discovered that T-DXd significantly improved progression-free survival compared with chemotherapy in the new study. The recent results highlighted the activity of T-DXd in all patient subgroups, including patients with rapid disease progression (< 6 months) following first-line endocrine-based therapy.
Although T-DXd was previously approved for use in a later-line setting among patients with HER2-low tumors, these recent findings demonstrate that it may be used earlier instead of chemotherapy in a broader patient population with advanced breast cancer, leading to a potential change in clinical practice.
Disclosure: For full disclosures of the study authors, visit nejm.org.
