This treatment differs from traditional chemotherapy, which targets any rapidly dividing cells, because targeted therapies are designed to interfere with genes and proteins specific to malignant cancer.

While targeted therapies have been shown to be helpful in patients with stage IV cancer, they have not been as helpful in patients with stage III cancer.

Recent studies show that cetuximab and panitumumab do not work as well for tumors that have specific changes, called mutations or alterations, to a gene called RAS.

The RAS gene family is a group of genes that make proteins involved in cell signaling pathways that control cell growth and cell death. Mutated (changed) forms of the RAS gene may be found in some types of cancer. These changes may cause cancer cells to grow and spread in the body.

Members of the RAS gene family include KRAS and NRAS.

ASCO recommends that all people with metastatic colorectal cancer who may receive an EGFR inhibitor have their tumors tested for RAS and RAF gene mutations.

Of these drugs, only tucatinib is currently approved specifically to treat colorectal cancer, although the others are all mentioned within NCCN treatment guideline. These drugs are generally used to treat cancer that has already been treated with chemotherapy, and the most common regimens include trastuzumab in combination with tucatinib, lapatinib, or pertuzumab.

Larotrectinib (Vitrakvi®) and entrectinib (Rozlytrek®) are types of targeted therapy that are not specific to a certain type of cancer but focus on a specific genetic change called an NTRK fusion. This type of genetic change is rare but is found in a range of cancers, including colorectal cancer. These medications are approved as treatment for colorectal cancer that is metastatic or cannot be removed with surgery and has worsened with other treatments.

Selpercatnib targets a specific mutation in the RET gene, which a small number of colorectal cancers possess. This drug is not specifically approved to treat colorectal cancer, but may be prescribed off-label. It is used in advanced cancers with mutations in the RET gene that are still growing despite other treatments.

This drug is used to treat people with metastatic colorectal cancer who have already received certain types of chemotherapy and other targeted therapies. Kinases are proteins near the surface of cells that carry important signals to the cells, stimulating it to grow or produce new blood vessels. Blocking these proteins can help stop the growth of cancer cells.

Targeted therapies can be administered through an IV or orally in pill- or capsule-form. Typically, monoclonal antibodies are administered through an IV. It depends on the drug and how it will be administered to determine whether you can undergo treatment at home or if you’ll need to visit a medical facility.

Since targeted therapies are designed to have a more focused action, they tend to have less severe side effects when compared to chemotherapies. However, the actual effects and their severity largely depend on the targeted action in question.

And since targeted therapies are a relatively new development in cancer treatment, the long-term effects are still being studied.

Immunotherapy is a type of targeted therapy drug for colorectal cancer patients, and one of the treatment options for some stage IV colorectal cancer patients. Read more about immunotherapy.