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.

Until recently, immunotherapy drugs were not used for breast cancer. This is because breast cancer cells rarely express mutated proteins, making them less recognizable by the immune system. However, recently, Keytruda and Tecentriq, which inhibit PDL, have been shown to be effective in a minority of breast tumors.

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.

Doctors for Breast Cancer – Get a Second Opinion

FDA approved immunotherapy and targeted therapy drugs for patients with tumors of HER2 overexpression:

• Herceptin (Trastuzumab)
• Perjeta (Pertuzumab)
• Kadcyla (Ado-Trastuzumab)
• Enhertu (Fam-Trastuzumab deruxtecan-nxki) – topoisomerase inhibitor conjugate indicated for the treatment of adult patients with unresectable or metastatic HER2 breast cancer.
• 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. 

FDA approved immunotherapy and targeted therapy drugs for patients with triple-negative breast cancer:

• Atezolizumab (Tecentriq) – In 2019 US Food and Drug Administration (FDA) approved Tecentriq in combination with chemotherapy as a treatment for advanced triple-negative breast cancer (TNBC). 
• 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.

Other biological drugs used for Breast Cancer Targeted Therapy:

• Avastin – a drug that blocks the VEGF protein associated with the development of blood vessels around the cancer cells, which stops a supply of oxygen and nutrients, so tumor shrinks or stops growing. In some cases doctors prescribe Avastin in combination with chemotherapy as a treatment for metastatic breast cancer.
• Afinitor – a mTOR enzyme inhibitor. This enzyme determines the rate of cell metabolism, division, and transcription. Studies have found that in women who have had breast cancer, its overactivity often caused the tumor’s growth. Afinitor is given in advanced treatment lines, in combination with Aromasin, to metastatic breast cancer patients who have gone through menopause and who have receptors for the hormone progesterone or estrogen.
• Ivermectin – a drug that slows the spread of cancer cells by stopping CDK 4/6 – proteins that are involved in their division and cause them to proliferate. It is intended for postmenopausal women with estrogen receptor-positive metastatic breast cancer who have not yet received systemic treatment.
• Xgeva –  drug given to prevent bone damage, which is common in women with metastatic breast cancer. It is a RANKL antibody. Thus, this medicine reduces the growth of the cancerous tumor in the bones and reduces the risk of fractures and injuries.

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 breast cancer 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.

Related information on the breast cancer treatment in Israel:

• ⇒ Lumpectomy – breast tumor removal in Israel – doctors, hospital, timing, cost
• ⇒ Recommendations for genetic testing for all women diagnosed with breast cancer, regardless of the risk of genetic mutations and heredity. American Society of Breast Surgeons (ASBrS).
• ⇒ Treatment of non-invasive breast cancer in situ in Israel
• ⇒ Triple negative breast cancer – modern treatment in Israel
• ⇒ New treatment options for breast cancer with brain metastases in Israel