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Immunotherapy is a type of drug therapy that stimulates the immune system. Interferon is a substance naturally made by the immune system, but it can also be made in the laboratory. Interferon reduces the growth and division of cancer cells.

Prior to the introduction of tyrosine kinase inhibitors (TKIs), interferon was considered first-line treatment for patients who could not receive an allogeneic stem cell transplantation. Currently, interferon therapy is less commonly used as a treatment for CML because, in general, TKIs are more effective and they have fewer side effects. While interferon is no longer used as a first-line treatment for CML, it may be an option for some patients who cannot tolerate the side effects of TKI therapy, or who are pregnant.

Interferon can cause significant side effects including

  • Trouble with concentration and memory
  • Mood changes
  • Flu-like symptoms such as muscle aches, fatigue, fever, chills, headaches, nausea and vomiting
  • Low red blood cell, white blood cell and platelet counts

These side effects continue as long as the patient uses the drug, but over time, it may become easier to tolerate. Many patients, however, cannot cope with these side effects every day and need to discontinue treatment with interferon.

Recently, interferon has re-emerged as an option in CML treatment, with the advent of pegylated formulations. Pegylation is a chemical process designed to increase a drug’s stability and retention time in the blood, while allowing for reduced dosing frequency. Pegylated interferon requires less frequent administration and is better tolerated by patients.

For information about the drugs listed on this page, visit Drug Listings.

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