How it is administered

Imatinib is taken by mouth as a tablet or oral solution. Tablets are available in 100 mg and 400 mg strengths. The oral solution contains 80 mg imatinib per mL. All doses should be taken with a meal and a large glass of water to help reduce stomach upset. If you have trouble swallowing tablets, they can be dissolved in water or apple juice.

For adults with chronic phase Chronic Myeloid Leukemia (CML), the typical starting dose is 400 mg once daily. For more advanced phases or after other treatments have failed, the dose may be higher. Pediatric doses are based on body surface area (mg/m²) and should not exceed 600 mg per day. Always use an accurate measuring device for the oral solution.

How it works

Imatinib is a type of medicine called a tyrosine kinase inhibitor. In Chronic Myeloid Leukemia (CML), a genetic change creates an abnormal protein called BCR-ABL tyrosine kinase, which causes white blood cells to grow uncontrollably. Imatinib works by blocking the activity of this abnormal protein.

By inhibiting BCR-ABL, imatinib stops the growth and multiplication of leukemia cells and can even cause them to die (apoptosis). This targeted action helps control the disease and can lead to remission. Imatinib also blocks other similar proteins (like c-Kit and PDGF receptors) that are involved in other cancers, but for CML, its main effect is on the BCR-ABL protein.

Who Should take it

Imatinib is recommended for:

• Adults and children newly diagnosed with Philadelphia chromosome positive (Ph+) chronic myeloid leukemia (CML) in chronic phase.
• Patients with Ph+ CML in blast crisis, accelerated phase, or chronic phase after failure of interferon-alpha therapy.

Imatinib may also be used in other blood cancers and conditions, but for CML, it is often the first-line treatment. It can be used in both adults and children (over 1 year old). Your doctor will determine the best dose and schedule for you based on your age, weight, and phase of CML.

Who should not take it

There are no absolute contraindications listed for imatinib, but it should not be used by anyone who is allergic to imatinib or any of its ingredients.

Caution is needed in people with severe liver or kidney impairment, heart problems, or those who are pregnant or breastfeeding (imatinib can harm the unborn baby and passes into breast milk). Women of childbearing potential should use effective contraception during treatment and for 14 days after stopping imatinib. Always discuss your full medical history with your doctor before starting imatinib.

Commonly used with

Imatinib is often used alone for CML, especially in the chronic phase. In some cases, it may be combined with other medications, such as chemotherapy agents for acute lymphoblastic leukemia (ALL) or with supportive treatments like antibiotics or growth factors if blood counts are low.

Patients who need anticoagulation (blood thinners) should use heparin rather than warfarin, as imatinib can interact with warfarin.

Commonly tested with

Imatinib has been compared in studies with interferon-alpha and cytarabine (Ara-C) in CML. It has also been tested against other tyrosine kinase inhibitors like nilotinib. In pediatric ALL, it is used in combination with chemotherapy.

Your doctor may also monitor your response to imatinib with regular blood tests, bone marrow exams, and molecular tests for BCR-ABL.