CHICAGO. Are approximately 37 thousand Italian women live with metastatic breast cancer, the most advanced and insidious form of the neoplasm, but thanks to research progress, the treatment prospects for these patients are increasing. The latest step forward comes from the congress of American society of clinical oncology (Asco) underway in Chicago: a new therapy with a drug-conjugated monoclonal antibody has been shown to reduce the risk of disease progression or death by 38% in patients with low and very low expression of the Her2 protein (Her2-low and Her2-ultralow), which in our country are several thousand every year.
This is demonstrated by the data from the phase 3 Destiny-Breast06 study on 866 patients, presented in the plenary session at the congress by Giuseppe Curigliano, member of the national board of Aiom (Italian Association of Medical Oncology) and director of the Division of new drugs and innovative therapies of the European Institute of Oncology (Ieo). The drug (trastuzumab deruxtecan) belongs to the category of drug-conjugated antibodies, i.e. it is made up of an antibody directed against the Her2 receptor, expressed on tumor cells, and a very powerful chemotherapy linked to this antibody.
It is, says Curigliano, “a sort of smart chemotherapy”. It has been shown to improve patient survival and has made it possible to avoid subsequent chemotherapy after anti-hormonal therapy. In metastatic breast cancer that is positive for hormone receptors, explains Curigliano , “After endocrine therapy in the early stages, the standard of care is chemotherapy, but this is associated with limited benefits. In the study, patients with Her2-low and Her2-ultralow metastatic breast cancer treated with first-line trastuzumab deruxtecan lived longer, without disease progression or worsening, compared to standard chemotherapy. These results represent a potential change in the way we classify and treat metastatic breast cancer, and the Destiny study allows us to expand the horizons of treatment to patients previously excluded from the benefits of targeted Her2 therapies.”
There are side effects reported but, the expert notes, “they can be managed. In particular, interstitial pneumonia can occur in 5-7% of patients, which is why it is advisable to carry out a periodic CT scan”. In Italy, in 2023, there were 55,900 new cases of breast cancer.
“The progress in the treatment of this neoplasm in recent years has been very important and chronicity is a reality for a significant number of patients – underlines Francesco Perrone, president of Aiom -. The results of the Destiny study highlight the importance of accurately determining the status of Her2. In this sense, the role of the multidisciplinary team in breast centers is fundamental, in particular the collaboration between the oncologist and the pathologist who carries out the diagnostic tests to define the molecular profile”.
For Saverio Cinieripresident of the Aiom Foundation, “these long-awaited data suggest that the drug may become a preferred first-line therapeutic option for patients with this type of metastatic breast cancer.”
In January 2023, trastuzumab deruxtecan was approved by the European Commission. The Italian Medicines Agency (Aifa) has already approved its reimbursement with a previous indication (in second line again for breast cancer) in December 2023.
