Imatinib is a targeted anti-cancer drug. It’s known as a tyrosine kinase inhibitor and it blocks the action of an abnormal enzyme called BCR-ABL. A major clinical trial shows imatinib brings about a complete hematologic response in 97 percent of patients who are in the chronic phase of CML. The drug brings about a complete cytogenetic response in 76 percent of patients. In almost 40 percent of patients, imatinib also brings about a significant reduction in the number of cells containing the Philadelphia chromosome when measured by the sensitive PCR molecular technique.
Most patients find side effects from imatinib mild and generally manageable. One common side effect is fluid buildup, often experienced as puffiness around the eyes. Other side effects can include bleeding, skin rash, diarrhea, nausea, muscle pain and fatigue. More serious side effects can include liver problems and abnormally low blood counts. There has been a report of rare, but serious, heart problems.
Adherence
The effectiveness of imatinib can decrease rapidly if not taken as prescribed. Patients are at risk of relapse if they do not take their full dose on schedule. Imatinib can be expensive, which may be one reason patients may fail to take the drug as recommended. Patients may also falsely believe that if they experience good control of their blood counts (hematological response) their continued use of imatinib is not important.