Findings from the phase 3 DESTINY-Breast04 trial supported the approval of fam-trastuzumab deruxtecan-nxki for HER2-low breast cancer in China.
China’s National Medical Products Administration has granted approval to fam-trastuzumab deruxtecan-nxki (Enhertu) monotherapy as a treatment for unresectable or metastatic HER2-low breast cancer following previous systemic treatment for metastatic disease or recurrence on or after 6 months of finishing adjuvant chemotherapy, according to a press release from AstraZeneca and Daiichi Sankyo.1
The HER2-directed antibody-drug conjugate was approved based on data from the phase 3 DESTINY-Breast04 trial (NCT03734029) that were presented at the 2022 American Society of Clinical Oncology Annual Meeting.2 In the overall patient population, the median progression-free survival was 9.9 months in the trastuzumab deruxtecan arm compared with 5.1 months in the physician’s choice of chemotherapy arm (HR, 0.50; 95% CI, 0.40-0.63; P <.0001). Additionally, the overall survival was 23.4 months compared with 16.8 months in each respective arm (HR, 0.64; 95% CI, 0.49-0.84 P = .001).
“Historically, breast cancer tumors with low levels of HER2 expression have been classified as HER2-negative and have not been eligible for treatment with HER2-directed therapies. With this approval in China, based on the results of the DESTINY-Breast04 trial, clinicians will now be able to identify and potentially treat a distinct patient population based on HER2-low status,” Binghe Xu, MD, director of the National Clinical Research Center for New Anticancer Drugs, tenured professor, and former director in the Department of Medical Oncology at the Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, said in the press release
Grade 3 or higher adverse effects were observed in 52.6% of those in the experimental arm vs 67.4% in the control arm.
Trastuzumab deruxtecan was approved by the FDA in August 2022 for patients with unresectable/metastatic HER2-low breast cancer based on the phase 3 DESTINY-Breast04 study.3