The treatment of advanced breast cancer of the “HER2 positive” type changes in the countries of the European Union. We are talking about about 20% of patients, for whom the European Commission has just approved the anti-HER2 trastuzumab deruxtecan conjugated antibody since the second line of treatment. So anticipating its use, since until now it could only be used by the third line.
Breast cancer, ‘smart’ drugs that fight the enemy with a ‘Trojan horse’
by Tiziana Moriconi
Metastatic HER2 positive breast cancer
In Italy, about 55,000 breast cancers are diagnosed each year and it is estimated that about one in 5 is HER2 positive, i.e. expresses high amounts of a protein called Receptor type 2 of human epidermal growth factor on its surface, which stimulates its growth. The news of the new approval concerns cases where the disease progresses and spreads to other tissues, becoming metastatic. In Italy, today, about 50,000 women live with metastatic breast cancer, according to the latest estimates.
The efficacy data of the new drug
Trastuzumab deruxtecan was approved in Europe for the third line of treatment at the end of 2020. The new approval, which covers the second line, is based on the results of the phase 3 study DESTINY-Breast03, published in the New England Journal of Medicine, in which trastuzumab deruxtecan demonstrated a 72% reduction in the risk of disease progression or death compared to the current standard of care, the conjugated antibody trastuzumab emtansine (or T-DM1). In the study, the median progression-free survival for patients treated with trastuzumab deruxtecan was not achieved, while that with T-DM1 was 6.8 months. “This approval represents an important milestone for European patients and clinicians, as patients previously treated for HER2-positive metastatic breast cancer with current standard treatment usually progress in less than a year. “, Explains Javier Cortés, head of the International Breast Cancer Center (IBCC) in Barcelona:” In the DESTINY-Breast03 study, the time to progression extended well beyond one year for patients who received trastuzumab deruxtecan, demonstrating the potential of this drug to become a new benchmark “.
Metastatic breast cancer, Europe approves a new drug
by Viola Rita, Tiziana Moriconi
The side effects
The drug is taken intravenously on its own. The most common adverse reactions reported in the trial were nausea (77%), fatigue (57.2%), vomiting (46.8%), alopecia (38%), neutropenia (34.6%), constipation (33, 9%), decreased appetite (33.7%), anemia (32.3%), diarrhea (30.7%), musculoskeletal pain (27.4%), increased transaminases (24.4%), leukopenia (24.1%), thrombocytopenia (23%) and upper respiratory tract infection (22.7%). Cases of interstitial lung disease or pneumonia were reported in 12% of patients, mostly non-serious.
Breast cancer, ‘smart’ drugs that fight the enemy with a ‘Trojan horse’
by Tiziana Moriconi
Anticipate treatments to increase survival
Already last October, based on the results of DESTINY-Breast03, the ESMO guidelines of clinical practice were updated to recommend the use of trastuzumab deruxtecan as a preferable second-line therapy for patients with HER2-positive metastatic breast cancer who had progressed after taxane and trastuzumab therapy. “With this extension of the trastuzumab deruxtecan indication we are now able to offer patients with HER2-positive metastatic breast cancer another treatment option earlier in their treatment pathway,” said Ken Keller, Global Head of ‘Oncology Business, President and CEO of Daiichi Sankyo. “Thanks to this approval, patients with HER2-positive metastatic breast cancer in Europe will have the opportunity to be treated with this drug at an even earlier stage of therapy, thus increasing the chances of achieving better clinical outcomes, in addition to those that we can already offer in more advanced stages, ”concluded Dave Fredrickson, Executive Vice President, AstraZeneca’s Oncology Business Unit.