NEW YORK – The European Medicines Agency (EMA) granted conditional approval on Wednesday for trastuzumab deruxtecan (Daiichi Sankyo/AstraZeneca's Enhertu) as a treatment for patients with metastatic, HER2-positive breast cancer who have previously received two or more anti-HER2 treatments.
The agency based its decision on the results from the single-arm, Phase II DESTINY-Breast01 trial, which enrolled 184 patients with metastatic HER2-positive breast cancer. Treatment with trastuzumab deruxtecan led to an objective response rate of 61 percent, with 6.5 percent of patients experiencing a complete response. The median duration of response was 20.8 months.
The EMA grants conditional marketing approval to drugs based on less data than typically required when the treatment addresses an unmet need, with the expectation that the sponsor will furnish more complete evidence on the drug's activity in the future.
"This expedited review underscores the practice-changing potential of [trastuzumab deruxtecan] for patients in the metastatic setting," Gilles Gallant, global head of oncology development and oncology R&D at Daiichi Sankyo, said in a statement. Trastuzumab deruxtecan "is the first-ever new medicine to be approved for breast cancer in Europe on the basis of Phase II single-arm data, and one of the fastest accelerated assessment procedures for an application in oncology."
Last March, the EMA's Committee for Medicinal Products for Human Use (CHMP) decided to review trastuzumab deruxtecan in this indication in an accelerated timeframe. In December, CHMP recommended approval for the drug in this setting, shortly after data from the DESTINY-Breast01 trial was presented at the San Antonio Breast Cancer Symposium.
Trastuzumab deruxtecan has already been approved for HER2-positive breast cancer in the US and in Japan. The drug was also approved in the US this week to treat advanced, HER2-positive gastric or gastroesophageal junction cancer.
The drug is being assessed in several ongoing Phase III breast cancer trials, which are evaluating trastuzumab deruxtecan in earlier lines of treatment, in patients with low HER2 expression, and as an adjuvant treatment.