Ado-trastuzumab emtansine
- Medical Review: Ilana Schlam, MD, MPH
Ado-trastuzumab emtansine (T-DM1, Kadcyla) combines the targeted therapy trastuzumab (Herceptin) with the chemotherapy medicine emtansine.
Ado-trastuzumab emtansine is an antibody-drug conjugate (ADC), a treatment that pairs a chemotherapy medicine with a targeted therapy. The trastuzumab helps deliver the chemotherapy directly to the HER2-positive tumor cells. This helps the drug reach the cancer cells and can help limit some of the chemotherapy side effects.
Who gets ado-trastuzumab emtansine
The FDA approved ado-trastuzumab emtansine for treatment of HER2-positive metastatic breast cancer that has grown despite treatment with trastuzumab and taxane chemotherapy.
Ado-trastuzumab emtansine is also approved to treat early-stage, HER2-positive breast cancer. It is only given in early-stage breast cancer if a person has already been given trastuzumab and chemotherapy before surgery, and breast cancer was still found at the time of surgery.
How ado-trastuzumab emtansine works
Trastuzumab attaches to the HER2 protein, allowing the chemotherapy emtansine to enter the cancer cell. Once inside the cell, it kills the cell. This way, ado-trastuzumab emtansine causes cancer cells to die, while limiting its effect on normal cells in the rest of the body.
How ado-trastuzumab emtansine is given
Ado-trastuzumab emtansine is given by vein once every 3 weeks.
For metastatic breast cancer, treatment continues as long as it controls the cancer, or until severe side effects develop. For early-stage breast cancer, it is given for 14 cycles after surgery.
Side effects and things to remember
Common side effects of ado-trastuzumab emtansine include:
- Neuropathy (tingling or numbness in the hands or feet)
- Liver problems (commonly, elevated liver enzymes)
- Bone and joint pain
- Diarrhea or constipation
- Low platelet count, which may result in bruising or bleeding
- Low potassium levels
- Low red blood cell count, which may result in fatigue and weakness
- Nausea or stomachache
- Reduced pumping function of the heart
Some people who take ado-trastuzumab emtansine develop a low white blood count, which may put you at risk for infection. Call your doctor right away if you show any symptoms of infection, such as a fever with chills.
Ado-trastuzumab emtansine can also decrease platelet counts, increasing the risk of bleeding or bruising. This can sometimes be dangerous. If you notice abnormal significant bleeding, call your doctor right away.
If you have serious side effects, your doctor may stop treatment for a time or switch you to another treatment.
Before starting ado-trastuzumab emtansine, tell your doctor about any history of heart or lung problems as well as any medicines you are taking, including vitamins, herbal supplements and over-the-counter medicines. You should not become pregnant while taking ado-trastuzumab emtansine.
Your doctor or nurse can help you manage your side effects. You can also visit our section on Side effects for more information.
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Living Beyond Breast Cancer is a national nonprofit organization that seeks to create a world that understands there is more than one way to have breast cancer. To fulfill its mission of providing trusted information and a community of support to those impacted by the disease, Living Beyond Breast Cancer offers on-demand emotional, practical, and evidence-based content. For over 30 years, the organization has remained committed to creating a culture of acceptance — where sharing the diversity of the lived experience of breast cancer fosters self-advocacy and hope. For more information, learn more about our programs and services.