NEW YORK – Daiichi Sankyo and AstraZeneca on Tuesday announced the start of a Phase III, head-to-head comparison of trastuzumab deruxtecan (Enhertu) and trastuzumab emtansine (Genentech's Kadcyla or T-DM1) as adjuvant treatment in early-stage, HER2-positive breast cancer patients after they've received neo-adjuvant therapy.
The trial, called DESTINY-Breast05, will enroll up to 1,600 breast cancer patients considered to be at high risk of disease recurrence because they have residual invasive disease in the breast or in axillary lymph nodes following neo-adjuvant treatment. The primary endpoint is investigator-assessed invasive disease-free survival, but researchers will also track patients' overall survival and safety on these treatments.
Daiichi Sankyo and AstraZeneca are conducting the global trial with the National Surgical Adjuvant Breast and Bowel Project Foundation, the German Breast Group, Arbeitsgemeinschaft Gynäkologische Onkologie (AGO-B), and the SOLTI Breast Cancer Research Group.
Based on results from the earlier DESTINY-Breast01 trial, trastuzumab deruxtecan was approved in the US and in Japan as a treatment for HER2-positive, unresectable or metastatic breast cancer patients who have previously received two or more anti-HER2 treatments. The drug was recently approved in Japan as a treatment for HER2-positive, unresectable, advanced or recurrent gastric cancer that has progressed after chemotherapy. The same gastric cancer indication is also under review in the US.
In DESTINY-Breast05, trastuzumab deruxtecan is being pitted against Genentech's trastuzumab emtansine since it is already approved for HER2-positive, early-stage breast cancer patients who have residual invasive disease despite treatment with a taxane or a regimen containing trastuzumab (Genentech's Herceptin).
"This research builds on the data from DESTINY-Breast01 which showed durability of response in previously treated, HER2-positive, metastatic breast cancer," Antoine Yver, global head of oncology research and development at Daiichi Sankyo, said in a statement. "DESTINY-Breast05 will evaluate Enhertu in patients with early HER2-positive breast cancer, versus T-DM1, the current standard of care, which marks the first time we will evaluate the clinical benefit of Enhertu in early breast cancer, reflecting our commitment to transforming treatment for even more patients with HER2 targetable disease."