Sloan-Kettering - Chronic Myelogenous Leukemia: Treatment

Newly Diagnosed?
We can help

Getting the correct diagnosis and the most appropriate treatment from the start is crucial

Physicians recommend a course of treatment for each CML patient that takes a number of factors into consideration: the stage of the disease; whether the patient has been treated already, with what, and how successfully; the number of blasts in the bone marrow; the results of cytogenetic testing; and the patient's overall health and other medical problems.

Imatinib (Gleevec®)

The standard initial treatment for chronic phase CML is a drug, in the form of a pill, called imatinib mesylate (Gleevec®). This drug blocks the action of the bcr/abl gene, the source of the abnormal protein found in CML. A very high percentage of patients in the chronic phase of the disease respond to imatinib. Typically, patients' complete blood count normalizes within the first three months of treatment, and the number of cells that contain the Philadelphia chromosome decreases.

Although the drug is effective at controlling the disease, it is not a cure. Patients are monitored frequently to assess their response to the drug and to check for side effects.

Over time some patients may become resistant to imatinib. In some instances, the bcr/abl protein becomes mutated (changed) and imatinib can no longer interact with it. A test used to determine the presence of the mutated protein is called a bcr/abl mutation test. If imatinib stops working, two other drugs -- dasatinib (Sprycel^®) and nilotinib (Tasigna^®) -- may be used. Some patients, fortunately a small number, cannot tolerate imatinib because of side effects of the drug.

Chronic Phase of CML

Our Transplant Program

Information about our transplant program

Imatinib controls the disease in most patients, but because the drug was licensed by the FDA somewhat recently, in 2001, doctors do not yet know how long patients will respond to the drug. As noted above, there are alternative drugs to imatinib that have also been shown to be highly effective. For those patients whose disease "breaks through" these drugs, another option called stem cell transplantation may be available. In this procedure, stem cells -- blood-forming cells -- are removed from an appropriate donor. The patient then receives a high dose of chemotherapy, sometimes in conjunction with radiation therapy, which destroys tumor cells but also damages the stem cells in the patient's bone marrow. The harvested stem cells are then administered (transplanted) to help rebuild the patient's immune system.

Accelerated Phase

For patients in the accelerated phase, treatment may include the options outlined above - imatinib, dasatinib, nilotinib, bone marrow transplantation, immunotherapy, or chemotherapy. Patients may also receive transfusions of blood or blood products to relieve symptoms.

Blast Phase

For patients in the blast phase, treatment generally includes chemotherapy in addition to imatinib (or dasatinib or nilotinib). This is a difficult phase of the disease to treat. Often, stem cell transplantation is recommended if an appropriate donor is identified and if the patient is healthy enough to undergo the procedure. Because the best results with stem cell transplantation are when the disease is in chronic or early accelerated phase disease, the aim of treatment in this phase is to get the patient back to the earlier phase of the disease.

Investigational Treatments

Find a Clinical Trial

Find out about new clinical trials for leukemia

Researchers are now developing new agents for cancer treatment at a faster rate than at any time since chemotherapeutic drugs were introduced in the late 1940s. Relying, in part, on the information that is emerging about the genetic basis of leukemia, investigators are pursuing a variety of strategies to control the disease -- approaches that can kill tumor cells directly, inhibit the body's production of substances that promote their growth, or enhance the immune response against leukemic cells.

Below are some of the therapies now being tested for CML. Studies of these and other promising new treatments are available to patients through clinical trials. For patients whose disease has recurred or is refractory, or who are not candidates for stem cell transplantation, clinical trials provide additional treatment options.

Targeted Therapies

Researchers are studying the most effective ways, including timing and dose, to use the targeted therapies now available (imatinib, dasatinib, nilotinib) and are working to create and test additional therapies that will block the aberrant gene and its variants.

Vaccines

Many leukemias, including CML and some solid tumors, are associated with chromosome translocations that create fusion genes -- new genes that include pieces of both the original chromosomes. These new genes contain instructions for new proteins, called fusion gene products. Researchers are using the amino acid sequences of these fusion proteins or mutated sequences to develop tumor-specific vaccines (called oncogene fusion point vaccines) for treating patients with cancer.

The first such vaccine for treating CML was developed by investigators at Memorial Sloan-Kettering and has been used in clinical trials to treat patients. The vaccine consists of a piece of the protein made by the Philadelphia chromosome gene and uses a portion of the fusion gene, called the bcr/abl fusion point, as its target. The goal of this therapeutic vaccine is to make the patients' immune system recognize and destroy the leukemia cells.

Cellular Therapy After Stem Cell Transplantation

In some patients who undergo stem cell transplantation, the disease recurs following the procedure. A strategy developed here at Memorial Sloan-Kettering and at other institutions -- a reinfusion of a particular type of white blood cell called lymphocytes from the original donor -- may boost these patients' ability to fight the disease. The effectiveness of this approach is now under study.