Key points
- There are several targeted therapies available for HER2+ metastatic breast cancer.
- Only trastuzumab (Herzuma) is publicly funded in New Zealand.
- Patients may benefit from prognostic testing or clinical trials to identify further treatment options.
Targeted therapies for HER2+ advanced breast cancer
There are a number of targeted therapies available to treat advanced HER2+ breast cancer.
Trastuzumab (Herzuma)
Trastuzumab is the most widely used targeted therapy to treat HER2+ mBC. It can be given with other chemotherapy drugs and is administered every three weeks via IV infusion - funded, or SC injection - unfunded, for as long as the patient continues to benefit. For more information about Herceptin and possible side effects see the Medsafe consumer information booklet.
Pertuzumab (Perjeta)
This is another monoclonal antibody treatment that is used to treat advanced/metastatic HER2+ breast cancer. It is given by intravenous infusion and is administered every three weeks. Perjeta is used at the same time as Herceptin and docetaxel chemotherapy. Perjeta is currently indicated for patients with HER2+ metastatic breast cancer who have not received previous anti-HER2 therapy or chemotherapy for their advanced disease. As of January 2017, Perjeta is funded for use in the New Zealand public health system. For more information about Perjeta and possible side effects see the Medsafe consumer information.
Trastuzumab emtansine (Kadcyla)/TDM-1
This is known as an antibody drug conjugate, combining an antibody and a chemotherapy drug. It can be used to treat metastatic HER2+ disease. Kadcyla uses the monoclonal antibody in trastuzumab to deliver DM-1 directly to the inside of the cancer cells while minimising the effects on healthy tissues. It is delivered every three weeks via IV infusion. Kadcyla is publicly funded for New Zealanders with HER2+ advanced breast cancer. For more information about Kadcyla and possible side effects see the Medsafe consumer information.
Lapatinib (Tykerb)
Lapatinib is a small-molecule drug belonging to a group known as Tyrosine Kinase Inhibitors, which target both HER2 and epidermal growth factor receptor (EGFR) pathways. It is publicly funded for people with metastatic HER2+ breast cancer that have not been treated with Herceptin, or for people who have not been able to tolerate Herceptin in this setting. Lapatinib is an oral chemotherapy, given in combination with capecitabine (Xeloda) or paclitaxel (Taxol). It can also be given with an aromatase inhibitor. Treatment can continue after chemotherapy for as long as the cancer responds. Lapatinib is not publicly funded in New Zealand. For more information about Lapatinib (Tykerb) and possible side effects see the Medsafe consumer information.
