Breast cancer immunotherapy and targeted therapy
Immunotherapy for breast cancer in Israel is a treatment that uses certain parts of the immune system to fight breast cancer. Immunotherapy drugs stimulate the immune system to search for cancer cells or add components (proteins) to the human immune system for killing cancer cells.
Traditional methods of treating breast cancer in Israel include chemotherapy, radiosurgery and surgery. Hormone therapy is also used in women with tumors with a positive hormone receptor as it helps to reduce the levels of estrogen and progesterone.
However, the advantage of breast cancer immunotherapy is that being biological by nature, it acts more softly and causes fewer side effects.
FDA approved immunotherapy and targeted therapy drugs for patients with tumors of HER2 overexpression:
- • Herceptin (Trastuzumab)
- • Perjeta (Pertuzumab)
- • Kadcyla (Ado-Trastuzumab)
- • Tukysa (Tucatinib) – a new oral drug approved in April 2020, a tyrosine kinase inhibitor, for the treatment of HER2-positive breast cancer. The drug is used in combination with chemotherapy Trastuzumab and Capecitabine for women who have received at least one line of treatment for the progressive stage of the disease. The main outcome of the study was progression-free survival, and all women were treated with Trastuzumab and Capecitabine and randomized to receive Tucatinib or placebo. About half of the women (48%) in the study were diagnosed with metastases to the brain at the start of the study. The median progression-free survival in the Tucatinib group was 7.8 months compared with 5.6 months in the placebo group. The progression-free survival results in the subgroup of women with cerebral metastases were almost the same. The median overall survival in the Tucatinib treatment group was 21.9 months compared to 17.4 months in the placebo group. The new drug is a rare success in the treatment of breast cancer with brain metastases, as previously the results of studies on this topic were not so successful.
FDA approved immunotherapy and targeted therapy drugs for patients with triple-negative breast cancer:
- • Atezolizumab (Tecentriq)
- • Nab-Paclitaxel (in combination with chemotherapy)
- • Sacituzumab Govitecan – Trodelvy – for metastatic and negative breast cancer for hormone receptors, following the failure of two previous treatment lines, approved 25/04/2020. Sacituzumab Govitecan, a vein-mediated antibody conjugate, is an active metabolite of Irinotecan and conjugated to a monoclonal antibody directed against an antigen that is widely expressed in negative breast cancer tumors for the three hormone receptors and promotes cancer cell growth. This approval is based on safety and efficacy results from a phase 1/2 study involving 108 women (median age of 56 years) who received at least two prior treatment lines for metastatic disease. Overall response rates were 33% (36 women), including three women with full response evidence. The median duration of response to treatment was 7.7 months. Of the women responding to treatment, 55.6% maintained response for at least six months and 16.7% maintained response after 1 year or more. The median progression-free survival was 5.5 months and the median overall survival was 13 months. There are risks of severe neutropenia and severe diarrhea during administration. Blood counts should be monitored during treatment and consideration should be given to G-CSF. The drug is prohibited for use in pregnant women.
Other immunotherapy drugs are currently being tested in clinical trials for breast cancer. Some of them showed impressive results.
Recent studies have shown that triple negative breast cancer is one of the subtypes that is most likely to respond the same as to treatment methods of melanoma.
PRECISION TREATMENT OF BREAST CANCER
A new approach to the treatment of breast cancer in Israel is the Personalized (precision) medicine. It arose as a reaction to the fact that not all women respond equally to the standard treatment of breast cancer that are suitable for the statistically average patient. Moreover, some patients respond to treatment with drugs that are used to treat other cancers.
Therefore, in recent years, our doctors have taken a course to personalize the treatment of breast cancer.
Immunotherapy drugs are also used in personalized treatment of breast cancer in Israel. In a personalized method, our doctors select drugs for each woman (based on molecular genomic tests for tumor tissue or blood samples) that may not be included in the standard treatment protocol, but show effect during the tests. As a result, a woman receives an individual list of drugs that has an effective prognosis for her tumor only.