Patients with low levels of the HER2 protein, too low to qualify for HER2 drugs, were filed under HER2-negative and treated with chemotherapy alone. A trial called DESTINY-Breast04 tested whether a newer antibody-drug could still find that smaller target.
Researchers led by Shanu Modi at Memorial Sloan Kettering randomized 557 patients with HER2-low metastatic breast cancer to trastuzumab deruxtecan or standard chemotherapy. The antibody-drug nearly doubled progression-free survival, 9.9 months versus 5.1 months, and cut the risk of death by 36 percent in the hormone-receptor-positive group.
The result mattered beyond the numbers, since it showed that HER2-low disease, long treated as untreatable by HER2 drugs, could respond to one after all. Later estimates suggested roughly half of tumors once labeled HER2-negative actually fall into this newly treatable category, and trials are now testing the drug earlier, before the cancer spreads.
Read the original study
A new target inside 'no target' cancer.
Source
- Modi, S., Jacot, W., Yamashita, T., Sohn, J., Vidal, M., Tokunaga, E., Tsurutani, J., Ueno, N. T., Prat, A., Chae, Y. S., Lee, K. S., Niikura, N., Park, Y. H., Xu, B., Wang, X., Gil-Gil, M., Li, W., Pierga, J.-Y., Im, S.-A., . . . Cameron, D. A. (2022). Trastuzumab Deruxtecan in Previously Treated HER2-Low Advanced Breast Cancer. New England Journal of Medicine, 387(1), 9–20. https://doi.org/10.1056/NEJMoa2203690