FDA Grants Priority Review for Trastuzumab Deruxtecan to Treat HER2-Positive Metastatic Breast Cancer

The Food and Drug Administration (FDA) has granted a priority review for trastuzumab deruxtecan (DS-8201), an investigational HER2-targeting antibody drug conjugate, for the treatment of patients with HER2-positive metastatic breast cancer.

The priority review was based on data from a second phase 1 trial, published by AstraZeneca and The Lancet Oncology,¹ and the pivotal phase 2 DESTINY-Breast01 trial. Safety and tolerability for the drug was consistent with results found in the original phase 1 trial data. Trastuzumab deruxtecan is designed to deliver chemotherapy inside the cancer cells and reduce exposure to chemotherapy, however, efficacy has not been established.

Adverse events (AEs) of any grade occurred in less than 30% of the patients. The most common AEs included nausea, decreased appetite, vomiting, alopecia, fatigue, anemia, diarrhea, and constipation. Detailed results from the DESTINY-Breast01 trial will be presented at the San Antonio Breast Cancer Symposium this December.

“Trastuzumab deruxtecan has the potential to transform the treatment landscape for patients with HER2-positive metastatic breast cancer who have limited treatment options,” José Baselga, MD, PhD, executive vice president, Research & Development Oncology, AstraZeneca, said in a press release.

The investigational agent was originally granted a breakthrough therapy designation in 2017 by the FDA to treat women with HER2-positive metastatic breast cancer who received trastuzumab (Herceptin), pertuzumab (Perjeta), and T-DM1 (Kadcyla) prior. At the time, the agent showed an objective response rate of 59.5% in a phase 1 trial of women with advanced breast cancer and prior exposure to T-DM1.²

“We are pleased that the FDA has accepted the application and granted priority review as we believe trastuzumab deruxtecan has the potential to redefine the treatment of patients with HER2-positive metastatic breast cancer,” Antoine Yver, MD, MSc, executive vice president and global head, Oncology Research and Development, Daiichi Sankyo, said in a statement.

The Prescription Drug User Fee Act (PDUFA) date for trastuzumab deruxtecan is set for the first quarter of fiscal year 2020.

References

• American Cancer Society. Breast Cancer HER2 Status. Available at https://www.cancer.org/cancer/breast-cancer/understanding-a-breast-cancer-diagnosis/breast-cancer-her2-status.html. Accessed August 2019.
• Tamura K, Tsurutani J, Takahashi S, et al. Trastuzumab deruxtecan (DS-8201a) in patients with advanced HER2-positive breast cancer previously treated with trastuzumab emtansine: a dose-expansion, phase 1 study. Lancet Oncol. 2019;20(6):816-826. doi: 10.1016/S1470-2045(19)30097-X.