Overview
11 DESCRIPTION Imatinib is a small molecule kinase inhibitor. Imatinib mesylate film-coated tablets are supplied as 100 mg and 400 mg tablets for oral administration. Each 100 mg tablet contains 119.5 mg of imatinib mesylate equivalent to 100 mg of imatinib free base. Each 400 mg tablet contains 478 mg of imatinib mesylate equivalent to 400 mg of imatinib free base.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Imatinib mesylate is a protein-tyrosine kinase inhibitor that inhibits the BCR-ABL tyrosine kinase, the constitutive abnormal tyrosine kinase created by the Philadelphia chromosome abnormality in CML. Imatinib inhibits proliferation and induces apoptosis in BCR-ABL positive cell lines as well as fresh leukemic cells from Philadelphia chromosome positive chronic myeloid leukemia. Imatinib inhibits colony formation in assays using ex vivo peripheral blood and bone marrow samples from CML patients. In vivo , imatinib inhibits tumor growth of BCR-ABL transfected murine myeloid cells as well as BCR-ABL positive leukemia lines derived from CML patients in blast crisis.
Indications
- 1 INDICATIONS AND USAGE Imatinib mesylate is a kinase inhibitor indicated for the treatment of: • Newly diagnosed adult and pediatric patients with Philadelphia chromosome positive chronic myeloid leukemia (Ph+ CML) in chronic phase ( 1.1 ) • Patients with Philadelphia chromosome positive chronic myeloid leukemia (Ph+ CML) in blast crisis (BC), accelerated phase (AP), or in chronic phase (CP) after failure of interferon-alpha therapy ( 1.2 ) • Adult patients with relapsed or refractory Philadelphia chromosome positive acute lymphoblastic leukemia (Ph+ ALL) ( 1.
Common Doses
- 400 mg
- 600 mg
- 340 mg
- 100 mg
Dosage
2 DOSAGE AND ADMINISTRATION Adults with Ph+ CML CP ( 2.2 ): 400 mg/day Adults with Ph+ CML AP or BC ( 2.2 ): 600 mg/day Pediatrics with Ph+ CML CP ( 2.3 ): 340 mg/m 2 /day Adults with Ph+ ALL ( 2.4 ): 600 mg/day Pediatrics with Ph+ ALL ( 2.5 ) 340 mg/m 2 /day Adults with MDS/MPD ( 2.6 ): 400 mg/day Adults with ASM ( 2.7 ): 100 mg/day or 400 mg/day Adults with HES/CEL ( 2.8 ): 100 mg/day or 400 mg/day Adults with DFSP ( 2.9 ): 800 mg/day Adults with metastatic and/or unresectable GIST ( 2.10 ): 400 mg/day Adjuvant treatment of adults with GIST ( 2.
Contraindications
- 4 CONTRAINDICATIONS None. None ( 4 ).
Side Effects
- 6 ADVERSE REACTIONS The following serious adverse reactions are described elsewhere in the labeling: Fluid Retention and Edema [see Warnings and Precautions ( 5.1 )] Hematologic Toxicity [see Warnings and Precautions ( 5.2 )] Congestive Heart Failure and Left Ventricular Dysfunction [see Warnings and Precautions ( 5.3 )] Hepatotoxicity [see Warnings and Precautions ( 5.4 )] Hemorrhage [see Warnings and Precautions ( 5.5 )] Gastrointestinal Disorders [see Warnings and Precautions ( 5.6 )] Hypereosinophilic Cardiac Toxicity [see Warnings and Precautions ( 5.
Interactions
- 7 DRUG INTERACTIONS CYP3A4 inducers may decrease imatinib mesylate C max and area under curve (AUC). ( 2.12 , 7.1 , 12.3 ) CYP3A4 inhibitors may increase imatinib mesylate C max and AUC. ( 7.2 , 12.3 ) Imatinib mesylate is an inhibitor of CYP3A4 and CYP2D6 which may increase the C max and AUC of other drugs. ( 7.3 , 7.4 , 12.3 ) Patients who require anticoagulation should receive low-molecular weight or standard heparin and not warfarin. ( 7.3 ) Imatinib mesylate tablets delay the clearance of methotrexate when methotrexate is used at high doses (> 500 mg/m 2 ). ( 7.5 ) 7.