Lung cancer begins with genetic mutations in genes. These mutations can cause cells to uncontrollably grow and divide, causing cancer.

Researchers have identified several different gene mutations associated with non-small cell lung cancer (NSCLC). Some of the genes found to have mutations include TP53, EGFR, KRAS, ALK, ROS1, BRAF, RET, MET, and NTRK genes.

So-called oncogenes control when cells divide, grow, and continue to live. Tumor suppressor genes, on the other hand, control the division of cells and trigger cells to die.

Mutations to these genes can “turn on” oncogenes and “turn off” tumor suppressor genes. These changes can cause cells to grow out of control and form tumors.

In lung cancer, people typically do not inherit these mutations. Instead, these acquired mutations can occur during a person’s lifetime.

This may be due to exposure to chemicals that cause cancer, such as those found in tobacco smoke. However, some genetic mutations can occur randomly, without an obvious outside cause.

Targeted therapies are treatments that hone in on gene mutations that cause cancer. By identifying mutations associated with lung cancer, researchers have been able to develop treatments to target specific mutations.

These treatments can turn off, or block, the signals that encourage growth and division of cells, stopping cells from living longer than they should, or destroying cancer cells.

The most common forms of targeted therapies fall into two categories:

  • Monoclonal antibodies: These block specific targets found on the outside of a cancer cell. They can also send toxic substances directly to a cancer cell. This enables chemotherapy and radiation therapy to better reach cancer cells.
  • Small-molecule drugs: These work by blocking signals that encourage cancer cells to divide, grow, and spread. One form of this therapy uses angiogenesis inhibitors. These stop the formation of new blood vessels around tumors, thereby starving the tumor of its needed nutrients.

A doctor may use targeted therapies alone or in combination with traditional treatments, such as chemotherapy, radiation, and surgery. In some cases, targeted therapies work when chemotherapy does not.

There are a number of targeted drug therapies for NSCLC.

Angiogenesis inhibitors

These drugs block the growth of new blood vessels surrounding tumors. This in turn starves the tumor of nutrients. Drugs in this category include bevacizumab (Avastin) and ramucirumab (Cyramza).

Drugs targeting ROS1 gene mutations

These drugs can shrink tumors in people who have advanced lung cancer with a ROS1 gene mutation.

Drugs in this category include:

  • crizotinib (Xalkori)
  • ceritinib (Zykadia)
  • lorlatinib (Lorbrena)
  • entrectinib (Rozlytrek)

Drugs targeting EGFR gene mutations

Called EGFR inhibitors, these drugs work by blocking signals that encourage cell growth.

Drugs in this category include:

  • erlotinib (Tarceva)
  • afatinib (Gilotrif)
  • gefitinib (Iressa)
  • osimertinib (Tagrisso)
  • dacomitinib (Vizimpro)

In many cases, these drugs can shrink tumors for at least several months. In the majority of cases, however, they may eventually stop working. This is often due to further gene mutations. When this happens, Tagrisso can target this mutation.

Drugs targeting ALK gene mutations

This group of drugs can shrink tumors in people with advanced lung cancer with an ALK genetic mutation. A doctor may recommend these drugs instead of chemotherapy or after chemotherapy has stopped working.

Drugs in this category include:

  • Xalkori
  • Zykadia
  • alectinib (Alecensa)
  • brigatinib (Alunbrig)
  • Lorbrena

Drugs targeting BRAF gene mutations

Healthcare professionals use these drugs to treat metastatic NSCLC that has a BRAF genetic mutation.

Drugs in this category include dabrafenib (Tafinlar) and trametinib (Mekinist).

Drugs targeting NTRK gene mutations

These drugs work by targeting and disabling proteins made by NTRK genes.

Drugs in this category include larotrectinib (Vitrakvi) and Rozlytrek.

Drugs targeting MET gene mutations

Known as MET inhibitors, these drugs attack the MET protein, which helps cells grow and spread.

Drugs in this category include capmatinib (Tabrecta) and tepotinib (Tepmetko).

Drugs targeting RET genetic mutations

Called RET inhibitors, these drugs work by attacking the RET protein.

Drugs in this category include selpercatinib (Retevmo) and pralsetinib (Gavreto).

Side effects vary depending on the medication. Common side effects of targeted therapies for lung cancer include:

  • nausea
  • diarrhea
  • high blood pressure
  • fatigue
  • skin rashes
  • loss of appetite
  • constipation
  • mouth sores
  • changes to vision

Targeted therapies have changed the treatment of NSCLC. One study found a decrease in mortality among people with NSCLC that corresponds with the approval of targeted therapies.

This is a rapidly growing field of research, and scientists are working continuously to identify new targets and create new therapies. Right now, clinical trials are taking place around the world to examine new targeted therapies and immunotherapies.

These trials include examining the role of immune monotherapies, combination immunotherapies, and treatments that combine targeted therapies with immunotherapies. Targeted therapies such as these can provide hope to people with lung cancer who may have limited treatment options.

There are several different genetic mutations associated with lung cancer. Identifying these mutations in people with NSCLC can help doctors find the best treatment for each individual.

These advances in treatment can help improve outcomes and pave the way for future therapies.