Researchers at LMU have successfully tested a novel medication that can significantly prolong the lives of patients with breast cancer. Brain metastases are frequently observed in patients with advanced HER2-positive breast cancer, and those who experience this condition have a low likelihood of surviving the following few years while receiving current treatments like radiotherapy and surgery.
A new medication has now been examined in a clinical study by an international team of researchers co-led by Professor Nadia Harbeck, Director of the Breast Center at LMU University Hospital. “With great results,” reports the oncologist. According to the findings to date, survival times increase substantially. The results of the trial have been published in the journal Nature Medicine.
Modern medicine classifies breast cancer into different types according to tumor biological characteristics. Fifty percent of patients with advanced breast cancer who have the tissue marker HER2 will suffer from brain metastases, which have not been successfully treated with drugs in the past due to the blood-brain barrier often preventing active substances from penetrating into the brain. New drugs are therefore urgently required.
One of these active substances is a so-called antibody-drug conjugate (ADC) called “trastuzumab deruxtecan.” Trastuzumab is an antibody that, once injected into the body, docks precisely to the HER2 protein. Its payload is the active ingredient deruxtecan, which kills cancer cells and is active in the tumor tissue while having minimal impact elsewhere in the body. “This is why we can use this active ingredient in the first place,” explains Harbeck. “Otherwise, it would be much too toxic.”
To determine the benefit of the ADC for HER2-positive breast cancer, the LMU oncologist launched the DESTINY-Breast12 study as one of the two principal investigators. Over 500 patients, with and without brain metastases, participated in the trial across 78 cancer centers in Western Europe, Japan, Australia, and the United States. The results showed that, on average, patients—including those with brain metastases—survived over 17 months without any progression of the cancer. More than 60 percent of patients survived 12 months without further tumor growth.
The researchers detected regression of the brain metastases in over 70 percent of participants, and 90 percent of all patients were alive one year after the start of treatment. “These findings,” says Nadia Harbeck, “offer hope to patients with brain metastases in particular.” The drug is already approved for use in standard practice.
Overall, the cancer specialist attests that the ADC has “great potential for the treatment of breast cancer.” An example of this is a large trial, ADAPT HER2 IV, which has been running for the past year under the initiative of the West German study group. This unique trial is available for patients with early, non-metastasized HER2-positive breast cancer in Germany. Patients receive infusions of the ADC just four times before surgery, which considerably simplifies and shortens the therapy.
Currently, three ADCs are approved for breast cancer treatment in Germany, and Harbeck believes, “there are many more to come.”