Targeted therapy

Targeted therapies are treatments that target specific proteins or markers on or within cancer cells that help the cells to grow. Targeted therapies may be used alone or with other targeted therapies, hormonal therapies, or chemotherapy medicines. Your doctor may also call these treatments tailored or biologic therapies.

Targeted therapies look for a specific feature of a cancer cell, attach to it, and destroy it. Only cancers with that feature will respond to the therapy. Some examples are:

• If the breast cancer tests positive for the HER2 receptor, you may be able to receive a targeted therapy that only targets HER2-positive cells
• Medicines that block the growth of blood vessels that most tumors need to grow
• Therapies that work like antibodies made by the immune system

Unlike chemotherapy, targeted therapies only kill only cells with that particular target, meaning fewer effects on healthy cells. For this reason, targeted therapies by themselves have far fewer side effects than chemotherapy medicines. But each targeted therapy has unique side effects that you should discuss with your doctor.

Hormonal therapies targeting the estrogen receptor and the progesterone receptors are the earliest examples of targeted therapy. Some targeted therapies can be used along with hormonal therapy to make hormonal therapy more effective at killing the cancer.

There are many kinds of targeted therapy, and researchers will likely find others as they learn more about what makes certain cancers grow. Targeted treatments are helping scientists and doctors personalize treatment plans so they can better treat different types of cancer.

Many forms of targeted therapy are being tested in clinical trials. They are given intravenously (by vein) or by mouth as a pill. Some treatments have already been approved by the FDA, but others are only available in clinical trials.

You will need tests to know whether the cancer will respond to targeted therapy. Sometimes, you may be offered a targeted therapy only in specific situations. You may be offered targeted therapy if you have:

• Early-stage HER2-positive breast cancer
• Metastatic HER2-positive breast cancer
• Metastatic hormone receptor-positive, HER2-negative breast cancer
• Metastatic triple-negative breast cancer

If you are interested in other targeted therapies, ask your doctor about a clinical trial.

Targeted therapy for early-stage breast cancer

Targeted therapy for breast cancer can be given either:

• Before surgery, which is called neoadjuvant therapy, or
• After surgery, which is called adjuvant therapy

Neoadjuvant therapy

Neoadjuvant therapy is full-body, or systemic, treatment given as a first step to shrink tumors or slow cancer spread before surgery.

Neoadjuvant therapy is more commonly used for breast cancer that is locally advanced, or has traveled outside the breast to other nearby organs or tissues such as lymph nodes, skin or chest wall.

You may be able to have neoadjuvant therapy if you have a HER2-positive tumor that is too large to remove with lumpectomy. The goal of neoadjuvant therapy would be to shrink the tumor to a size that could allow you to have lumpectomy instead of mastectomy.

Targeted therapies that may be used as neoadjuvant therapy for HER2-positive breast cancer are:

• Trastuzumab (Herceptin): This medicine is given with chemotherapy. If you get trastuzumab before surgery, you will likely get it after surgery to complete your treatment.
• Pertuzumab (Perjeta): Pertuzumab is given with trastuzumab and chemotherapy before surgery. Afterward, you would continue taking trastuzumab to finish your treatment.

Trastuzumab and pertuzumab are part of a class of drugs called monoclonal antibodies.

After neoadjuvant targeted therapy, you may have tests, such as a mammogram or MRI, to see how the cancer responded to therapy. Then, surgery will be scheduled.

After your surgery, a pathologist will check the tissue that was removed for any signs of cancer. In some cases, there may be a complete response to therapy, meaning the doctor can find no evidence of remaining disease, or NED. When cancer completely goes away, it is linked to better overall outcomes. But you will still need to finish your treatment plan to reduce the risk of recurrence.

Adjuvant therapy

Adjuvant therapy is treatment given after surgery to lower the risk of the breast cancer coming back and increase the chance of long-term survival. The goal is to kill any cancer cells that may have traveled away from the breast or lymph nodes. If you are at higher risk of recurrence, you are more likely to need adjuvant therapy.

For early-stage HER2-positive breast cancer, adjuvant targeted therapy treatment options include:

• Trastuzumab
• Pertuzumab
• Neratinib (Nerlynx), a targeted therapy known as a tyrosine kinase inhibitor

For early-stage hormone receptor-positive, HER2-negative breast cancer, adjuvant targeted therapies include medicines called CDK 4/6 inhibitors. They are:

• Abemaciclib (Verzenio)
• Ribociclib (Kisqali)

For early-stage breast cancer in people who test positive for an inherited BRCA gene mutation, a targeted therapy called olaparib (Lynparza) is available. Olaparib is a type of medicine called a PARP inhibitor. To be eligible to take olaparib, the breast cancer can be either:

• Hormone receptor-positive and HER2-negative, or
• Triple-negative

New targeted therapies are being studied in clinical trials for early-stage breast cancer. If you’re interested in learning more about trials available to you, talk with your doctor. You can also visit the Early-stage trial search tool to look for current trials.

Targeted therapy for metastatic breast cancer

There are several targeted therapy medicines approved to treat metastatic breast cancer.

Antibody-drug conjugates

Antibody-drug conjugates pair a targeted therapy with a powerful chemotherapy. The targeted therapy delivers the chemotherapy directly into cancer cells. Here are the antibody-drug conjugates approved to treat metastatic breast cancer:

• Ado-trastuzumab emtansine (Kadcyla), which treats HER2-positive metastatic breast cancer
• Datopotamab deruxtecan (Datroway), which treats hormone receptor-positive, HER2-negative metastatic breast cancer
• Sacituzumab govitecan (Trodelvy), which treats hormone receptor-positive, HER2-negative metastatic breast cancer and triple-negative metastatic breast cancer
• Trastuzumab deruxtecan (Enhertu), which treats HER2-positive, HER2-low, and HER2-ultralow metastatic breast cancer

CDK 4/6 inhibitors

There are three cyclin-dependent kinase 4/6 (CDK 4/6) inhibitors approved to treat hormone receptor-positive, HER2-negative metastatic breast cancer:

• Abemaciclib (Verzenio)
• Palbociclib (Ibrance)
• Ribociclib (Kisqali)

You can learn more about CDK 4/6 inhibitors on the Targeted therapy for hormone receptor-positive breast cancer page.

Monoclonal antibodies

Monoclonal antibodies are a type of targeted therapy for HER2-positive metastatic breast cancer. They include:

• Margetuximab (Margenza)
• Trastuzumab
• Pertuzumab

PARP inhibitors

PARP inhibitors are targeted therapies approved to treat metastatic breast cancer in people who test positive for an inherited BRCA mutation. The cancer can be hormone receptor-positive and HER2-negative, or triple-negative. These medicines include:

• Olaparib
• Talazoparib

Other targeted therapies for metastatic breast cancer

There are several other targeted therapies available to treat metastatic breast cancer. These therapies target cancer cell features such as gene mutations, enzymes, and proteins. They include:

• Alpelisib (Piqray), a PI3K inhibitor, which treats hormone receptor-positive metastatic breast cancer
• Capivasertib (Truqap), an AKT inhibitor, which treats hormone receptor-positive, HER2-negative metastatic breast cancer
• Everolimus (Afinitor), an mTOR inhibitor, which treats hormone receptor-positive, HER2-negative metastatic breast cancer
• Inavolisib (Itovebi), a PI3K inhibitor, which treats hormone receptor-positive, HER2-negative metastatic breast cancer
• Lapatinib (Tykerb), a dual tyrosine kinase inhibitor, which treats HER2-positive metastatic breast cancer
• Tucatinib (Tukysa), a tyrosine kinase inhibitor, which treats HER2-positive metastatic breast cancer

Many targeted therapies for metastatic breast cancer are being tested in clinical trials. Clinical trials allow you to try a new therapy or combination of therapies prior to FDA approval. Visit the Metastatic trial search page to learn about current trials.