Oncologists hope that the drug Enhertu, developed by AstraZeneca and Daiichi Sankyo, will change the way the most common advanced breast cancer is treated. The results of the clinical trial of the drug, an antibody therapy (Trastuzumab Deruxtecan), showed that it significantly improved the survival rates of patients compared to chemotherapy, even patients with tumor metastases in their body.
The announcement was made at a conference of the American Society of Clinical Oncology (ASCO) in Chicago and involved a study of 557 patients, according to Reuters and the Financial Times. It is the first time that targeted therapy has improved survival in patients with HER2-low or negative metastatic cancer.
The drug reduced the risk of cancer by 49% and reduced the risk of death by 36% compared to standard chemotherapy. Patient survival without disease exacerbation (the period during which the tumor was stable or contracted and the patient's condition did not begin to worsen) increased from an average of 5,4 months in the case of chemotherapy to 10,1 months with Enhertu, that is, it almost doubled.
In hormone-sensitive cancer patients (which is the majority), the median survival increased from 17,5 months with chemotherapy to 23,9 months, or at least half a year (6,4 months). In the smaller group of patients with tumor-insensitive tumors, life expectancy was proportional (6,3 months).
The two companies said they would use the above positive results - published in the New England Journal of Medicine - to seek approval from global regulators for widespread use of the drug in patients with HER2-low-grade breast cancer. They estimate that this will be achieved in a few months.
The Japanese Daiichi announced that it is conducting studies in early stage patients with breast cancer, to see if the drug is more effective than the existing ones in these cases and whether it could cure this cancer in the future. Enhertu is designed to target and shrink cancer cells that express the HER2 protein (which helps tumors grow), while reducing damage to healthy cells. The treatment was already approved in 2019 by the US Food and Drug Administration (FDA) for a smaller group of patients with advanced HER2-positive breast cancer (about 15% of all patients), but the new clinical study shows that Enhertu also "works" on the most common cancers with low HER2 or HER2-negative levels.
For these patients the treatment options have been limited until today. Existing anticancer drugs such as Roche Herceptin have so far only benefited the minority of HER2-positive breast cancers, leaving the majority of advanced patients with low HER2 to rely on standard chemotherapy for preoperative treatment. disease.
Intravenous Enhertu has also already been approved in the US for certain types of gastric cancer, and has also raised hopes for some lung cancers. AstraZeneca oncology executive vice president David Fredrickson said Enhertu has the potential to become a "multi-successful drug" by transforming the treatment of different types of breast cancer, as well as gastrointestinal and lung cancers.
As early as 2021, global drug sales outside Japan reached $ 426 million and the prospect, according to analysts, is to reach $ 2,5 to $ 6,6 billion a year, given that breast cancer has now surpassed lung cancer and has become the most commonly diagnosed cancer in the world.
"Miracle" medicine for rectal cancer
The results of another small clinical trial of a new drug, dostarlimab, for rectal cancer (it is the final part of the colon that ends in the anus) are very positive. The study of 12 patients, published in the New England Journal of Medicine and also presented at a conference of the American Society of Clinical Oncology, according to the New York Times, showed that the cancer suddenly disappeared in all patients and did not was no longer detectable by any method (physical examination, endoscopy, magnetic resonance imaging or PET).
Researcher Dr. Luis Diaz of the Memorial Cancer Center Sloan Kettering said he was not aware of any other study in which one treatment had completely eradicated cancer from all the patients involved, even though the number was small. "I think this is the first time this has happened in the history of cancer," he said. However, it remains to be seen whether the patients were actually treated, so a larger clinical trial should follow.
The drug was administered every three weeks for six months and its cost is high (about $ 11.000 per dose). Its role is to facilitate the immune system to selectively detect and destroy cancer cells. Patients did not experience significant side effects.
Links to scientific publications:
https://www.nejm.org/doi/full/10.1056/NEJMoa2203690?query=featured_home
https://www.nejm.org/doi/full/10.1056/NEJMoa2201445?query=featured_home