What is the treatment for chronic myeloid leukemia (CML)?

Systemic treatment for chronic myeloid leukemia (CML) is one example of a modern medicine success story. This disease results classically (though not always) from a wrong movement of genetic pieces between chromosomes. The result of these two pieces, called breakpoint cluster region (BCR) and Albeson (ABL), moving together erroneously forms what is termed the Philadelphia chromosome, which is found to be present in many patients with CML.

Historically, the disease was treated with a type of immunotherapy called interferon alpha (IFN) which didn't have great success and caused significant side effects for patients. However, over the past decade, thanks to advances in molecular biology, a new class of drugs has become the standard of care, resulting in better outcomes, including less toxicity from treatment. "Shotgun" treatment to the entire immune system with IFN has been replaced with targeted drug therapy using a class of tyrosine kinase inhibitors (TKIs). More specifically, a subgroup of TKIs that inhibits or blocks BCR-ABL has been shown to be much more effective than IFN in a randomized controlled trial (RCT). The most common BCR-ABL inhibitor in use over the past several years has been imatinib. However, two major RCTs revealed a significant benefit to second generation BCR-ABL inhibitors, nilotinib and dasatinib. These drugs have become the new standard for treatment of chronic phase CML that's Philadelphia chromosome positive.