Gleevec Drug Information

Drug Administration

The prescribed dose should be administered orally, with a meal and a large glass of water. For patients unable to swallow the film-coated tablets, the tablets may be dispersed in a glass of water or apple juice. The required number of tablets should be placed in the appropriate volume of beverage (approximately 50 mL for a 100-mg tablet, and 200 mL for a 400-mg tablet) and stirred with a spoon.

The suspension should be administered immediately after complete disintegration of the tablet(s). For daily dosing of 800 mg and above, dosing should be accomplished using the 400-mg tablet to reduce exposure to iron. Treatment may be continued as long as there is no evidence of progressive disease or unacceptable toxicity.

Adult Patients With Ph+ CML CP, AP, or BC

The recommended dose of Gleevec is 400 mg/day for adult patients in chronic phase CML and 600 mg/day for adult patients in accelerated phase or blast crisis. In CML, a dose increase from 400 mg to 600 mg in adult patients with chronic phase disease, or from 600 mg to 800 mg (given as 400 mg twice daily) in adult patients in accelerated phase or blast crisis may be considered in the absence of severe adverse drug reaction and severe non-leukemia related neutropenia or thrombocytopenia in the following circumstances: disease progression (at any time), failure to achieve a satisfactory hematologic response after at least 3 months of treatment, failure to achieve a cytogenetic response after 6 to 12 months of treatment, or loss of a previously achieved hematologic or cytogenetic response.

Pediatric Patients With Ph+ CML CP

The recommended dose of Gleevec for children with newly diagnosed Ph+ CML is 340 mg/m 2 /day (not to exceed 600 mg). Gleevec treatment can be given as a once daily dose or the daily dose may be split into two–one portion dosed in the morning and one portion in the evening. There is no experience with Gleevec treatment in children under 1 year of age.

Adult Patients With Ph+ ALL

The recommended dose of Gleevec is 600 mg/day for adult patients with relapsed/refractory Ph+ ALL.

Adult Patients With MDS/MPD Determine

PDGFRb gene rearrangements status prior to initiating treatment. The recommended dose of Gleevec is 400 mg/day for adult patients with MDS/MPD.

Adult Patients With ASM Determine

D816V c-Kit mutation status prior to initiating treatment. The recommended dose of Gleevec is 400 mg/day for adult patients with ASM without the D816V c-Kit mutation. If c-Kit mutational status is not known or unavailable, treatment with Gleevec 400 mg/day may be considered for patients with ASM not responding satisfactorily to other therapies.

For patients with ASM associated with eosinophilia, a clonal hematological disease related to the fusion kinase FIP1L1-PDGFRα, a starting dose of 100 mg/day is recommended. Dose increase from 100 mg to 400 mg for these patients may be considered in the absence of adverse drug reactions if assessments demonstrate an insufficient response to therapy.

Adult Patients With HES/CEL

The recommended dose of Gleevec is 400 mg/day for adult patients with HES/CEL. For HES/CEL patients with demonstrated FIP1L1-PDGFRα fusion kinase, a starting dose of 100 mg/day is recommended.

Adult Patients With Metastatic and/or Unresectable GIST The recommended dose of Gleevec is 400 mg/day for adult patients with unresectable and/or metastatic, malignant GIST. A dose increase up to 800 mg daily (given as 400 mg twice daily) may be considered, as clinically indicated, in patients showing clear signs or symptoms of disease progression at a lower dose and in the absence of severe adverse drug reactions.

Adult Patients With Adjuvant GIST

The recommended dose of Gleevec is 400 mg/day for the adjuvant treatment of adult patients following complete gross resection of GIST. In clinical trials, one year of Gleevec and three years of Gleevec were studied. In the patient population defined in Study 2, three years of Gleevec is recommended.

The optimal treatment duration with Gleevec is not known.

Dose Modification Guidelines Concomitant Strong

• CYP3A4 inducers: The use of concomitant strong CYP3A4 inducers should be avoided (e.g., dexamethasone, phenytoin, carbamazepine, rifampin, rifabutin, rifampacin, phenobarbital). If patients must be coadministered a strong CYP3A4 inducer, based on pharmacokinetic studies, the dosage of Gleevec should be increased by at least 50%, and clinical response should be carefully monitored.
• Hepatic Impairment: Patients with mild and moderate hepatic impairment do not require a dose adjustment and should be treated per the recommended dose. A 25% decrease in the recommended dose should be used for patients with severe hepatic impairment.
• Renal Impairment: Patients with moderate renal impairment (creatinine clearance = 20-39 mL/min) should receive a 50% decrease in the recommended starting dose and future doses can be increased as tolerated. Doses greater than 600 mg are not recommended in patients with mild renal impairment (CrCL = 40-59 mL/min). For patients with moderate renal impairment doses greater than 400 mg are not recommended. Imatinib should be used with caution in patients with severe renal impairment. A dose of 100 mg/day was tolerated in two patients with severe renal impairment.

Dose Adjustment for Hepatotoxicity and Non-Hematologic Adverse Reactions If elevations in bilirubin greater than 3 times the institutional upper limit of normal (IULN) or in liver transaminases greater than 5 times the IULN occur, Gleevec should be withheld until bilirubin levels have returned to a less than 1.5 times the IULN and transaminase levels to less than 2.5 times the IULN. If a severe non-hematologic adverse reaction develops (such as severe hepatotoxicity or severe fluid retention), Gleevec should be withheld until the event has resolved. Thereafter, treatment can be resumed as appropriate depending on the initial severity of the event.

Dose Adjustment for Hematologic Adverse Reactions

Dose reduction or treatment interruptions for severe neutropenia and thrombocytopenia are recommended as indicated in Table 1. Table 1: Dose Adjustments for Neutropenia and Thrombocytopenia

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Chronic Myeloid Leukemia The majority of Gleevec-treated patients experienced adverse reactions at some time. Gleevec was discontinued due to drug-related adverse reactions in 2.4% of patients receiving Gleevec in the randomized trial of newly diagnosed patients with Ph+ CML in chronic phase comparing Gleevec versus IFN+Ara-C, and in 12.5% of patients receiving Gleevec in the randomized trial of newly diagnosed patients with Ph+ CML in chronic phase comparing Gleevec and nilotinib.

Gleevec was discontinued due to drug-related adverse reactions in 4% of patients in chronic phase after failure of interferon-alpha therapy, in 4% of patients in accelerated phase and in 5% of patients in blast crisis. The most frequently reported drug-related adverse reactions were edema, nausea and vomiting, muscle cramps, musculoskeletal pain, diarrhea and rash (Table 2 and Table 3 for newly diagnosed CML, Table 4 for other CML patients). Edema was most frequently periorbital or in lower limbs and was managed with diuretics, other supportive measures, or by reducing the dose of Gleevec.

The frequency of severe superficial edema was 1.5%-6%. A variety of adverse reactions represent local or general fluid retention, including pleural effusion, ascites, pulmonary edema, and rapid weight gain with or without superficial edema. These reactions appear to be dose related, were more common in the blast crisis and accelerated phase studies (where the dose was 600 mg/day), and are more common in the elderly.

These reactions were usually managed by interrupting Gleevec treatment and using diuretics or other appropriate supportive care measures. These reactions may be serious or life threatening. Table 2: Adverse Reactions Regardless of Relationship to Study Drug Reported in Newly Diagnosed CML Clinical Trial in the Gleevec Versus IFN+Ara-C Study (Greater Than or Equal to 10% of Gleevec-Treated Patients) Abbreviations: CML, chronic myeloid leukemia; CNS, central nervous system; CTC, common terminology criteria; GI, gastrointestinal; IFN, Interferon-alpha. NCI Common Terminology Criteria for Adverse Events, version 3.0.

Table 3: Most Frequently Reported Non-Hematologic Adverse Reactions (regardless of relationship to study drug) in Patients With Newly Diagnosed Ph+ CML-CP in the Gleevec Versus Nilotinib Study (Greater Than or Equal to 10% in Gleevec 400 mg Once Daily or Nilotinib 300 mg Twice Daily Groups) 60-Month Analysis a 1 Table 4: Adverse Reactions Regardless of Relationship to Study Drug Reported in Other CML Clinical Trials (Greater Than or Equal to 10% of All Patients in Any Trial) Abbreviations: CML, chronic myeloid leukemia; IFN, Interferon-alpha. Hematologic and Biochemistry Laboratory Abnormalities Cytopenias, and particularly neutropenia and thrombocytopenia, were a consistent finding in all studies, with a higher frequency at doses greater than or equal to 750 mg (Phase 1 study). The occurrence of cytopenias in CML patients was also dependent on the stage of the disease.

In patients with newly diagnosed CML, cytopenias were less frequent than in the other CML patients (see Tables 5, 6, and 7). These reactions can usually be managed with either a reduction of the dose or an interruption of treatment with Gleevec, but may require permanent discontinuation of treatment. Table 5: Laboratory Abnormalities in Newly Diagnosed CML Clinical Trial Table 6: Percent Incidence of Clinically Relevant Grade 3/4* Laboratory Abnormalities in the Newly Diagnosed CML Clinical Trial ( 0 Table 7: Laboratory Abnormalities in Other CML Clinical Trials Abbreviations: CML, chronic myeloid leukemia; CTC, common terminology criteria; IFN, Interferon-alpha; SGOT, serum glutamic-oxaloacetic transaminase is now referred to as aspartate aminotransferase (AST); SGPT, serum glutamic-pyruvic transaminase is now referred to as alanine aminotransferase (ALT). 9 /L), anemia (hemoglobin greater than or equal to 65–80 g/L, Grade 4 less than 65 g/L), elevated creatinine (Grade 3 greater than 3–6 x upper limit normal range, Grade 4 greater than 6 x ULN), elevated bilirubin 0 Hepatotoxicity Severe elevation of transaminases or bilirubin occurred in approximately 5% of CML patients (see Tables 6 and 7) and were usually managed with dose reduction or interruption (the median duration of these episodes was approximately 1 week).

Treatment was discontinued permanently because of liver laboratory abnormalities in less than 1.0% of CML patients. One patient, who was taking acetaminophen regularly for fever, died of acute liver failure. Bilirubin elevation was observed in 2.7% of patients.

Adverse Reactions in Pediatric Population Single-Agent Therapy The overall safety profile of pediatric patients treated with Gleevec in 93 children studied was similar to that found in studies with adult patients, except that musculoskeletal pain was less frequent (20.5%) and peripheral edema was not reported. Nausea and vomiting were the most commonly reported individual adverse reactions with an incidence similar to that seen in adult patients. Most patients experienced adverse reactions at some time during the study.

The incidence of Grade 3/4 events across all types of adverse reactions was 75%; the events with the highest Grade 3/4 incidence in CML pediatric patients were mainly related to myelosuppression. In Combination with Multi-Agent Chemotherapy Pediatric and young adult patients with very high risk ALL, defined as those with an expected 5 year event-free survival (EFS) less than 45%, were enrolled after induction therapy on a multicenter, non-randomized cooperative group pilot protocol. Patients with Ph+ ALL (n = 92) were assigned to receive Gleevec and treated in 5 successive cohorts.

Gleevec exposure was systematically increased in successive cohorts by earlier introduction and more prolonged duration. The safety of Gleevec given in combination with intensive chemotherapy was evaluated by comparing the incidence of Grade 3 and 4 adverse events, neutropenia (less than 750/mcL) and thrombocytopenia (less than 75,000/mcL) in the 92 patients with Ph+ ALL compared to 65 patients with Ph- ALL enrolled on the trial who did not receive Gleevec. The safety was also evaluated comparing the incidence of adverse events in cycles of therapy administered with or without Gleevec.

The protocol included up to 18 cycles of therapy. Patients were exposed to a cumulative total of 1425 cycles of therapy, 778 with Gleevec, and 647 without Gleevec. The adverse events that were reported with a 5% or greater incidence in patients with Ph+ ALL compared to Ph- ALL or with a 1% or greater incidence in cycles of therapy that included Gleevec are presented in Table 8.

Table 8: Adverse Reactions Reported More Frequently in Patients Treated With Study Drug (Greater Than 5%) or in Cycles With Study Drug (Greater Than 1%) 9 Adverse Reactions in Other Subpopulations In older patients (greater than or equal to 65 years old), with the exception of edema, where it was more frequent, there was no evidence of an increase in the incidence or severity of adverse reactions. In women there was an increase in the frequency of neutropenia, as well as Grade 1/2 superficial edema, headache, nausea, rigors, vomiting, rash, and fatigue. No differences were seen that were related to race but the subsets were too small for proper evaluation.

Acute Lymphoblastic Leukemia The adverse reactions were similar for Ph+ ALL as for Ph+ CML. The most frequently reported drug-related adverse reactions reported in the Ph+ ALL studies were mild nausea and vomiting, diarrhea, myalgia, muscle cramps, and rash. Superficial edema was a common finding in all studies and were described primarily as periorbital or lower limb edemas.

These edemas were reported as Grade 3/4 events in 6.3% of the patients and may be managed with diuretics, other supportive measures, or in some patients by reducing the dose of Gleevec. Myelodysplastic/Myeloproliferative Diseases Adverse reactions, regardless of relationship to study drug, that were reported in at least 10% of the patients treated with Gleevec for MDS/MPD in the Phase 2 study, are shown in Table 9. Table 9: Adverse Reactions Regardless of Relationship to Study Drug Reported (More Than One Patient) in MPD Patients in the Phase 2 Study Greater Than or Equal to 2 Aggressive Systemic Mastocytosis All aggressive systemic mastocytosis (ASM) patients experienced at least one adverse reaction at some time.

The most frequently reported adverse reactions were diarrhea, nausea, ascites, muscle cramps, dyspnea, fatigue, peripheral edema, anemia, pruritus, rash, and lower respiratory tract infection. None of the 5 patients in the Phase 2 study with ASM discontinued Gleevec due to drug-related adverse reactions or abnormal laboratory values. Hypereosinophilic Syndrome and Chronic Eosinophilic Leukemia The safety profile in the HES/CEL patient population does not appear to be different from the safety profile of Gleevec observed in other hematologic malignancy populations, such as Ph+ CML.

All patients experienced at least one adverse reaction, the most common being GI, cutaneous and musculoskeletal disorders. Hematological abnormalities were also frequent, with instances of CTC Grade 3 leukopenia, neutropenia, lymphopenia, and anemia. Dermatofibrosarcoma Protuberans Adverse reactions, regardless of relationship to study drug, that were reported in at least 10% of the 12 patients treated with Gleevec for DFSP in the Phase 2 study are shown in Table 10.

The most frequently reported adverse reactions were edema, fatigue, nausea, abdominal pain, diarrhea, rash, vomiting, myalgia, anemia, and anorexia. Drug was discontinued for adverse reactions in a total of 89 patients (5.4%). Severe (CTC Grade 3/4) edema was observed in 182 patients (11.1%).

Overall the incidence of all grades of adverse reactions and the incidence of severe adverse reactions (CTC Grade 3 and above) were similar between the two treatment arms except for edema, which was reported more frequently in the 800 mg group. Table 12: Number (%) of Patients With Adverse Reactions Regardless of Relationship to Study Drug Where Frequency is Greater Than or Equal to 10% in any One Group (Full Analysis Set) in the Phase 3 Unresectable and/or Malignant Metastatic GIST Clinical Trials Clinically relevant or severe abnormalities of routine hematologic or biochemistry laboratory values were not reported or evaluated in the Phase 3 GIST trials. Severe abnormal laboratory values reported in the Phase 2 GIST trial are presented in Table 13.

Table 13: Laboratory Abnormalities in the Phase 2 Unresectable and/or Malignant Metastatic GIST Trial Abbreviations: CTC, common terminology criteria; GIST, gastrointestinal stromal tumors; SGOT, serum glutamic-oxaloacetic transaminase is now referred to as aspartate aminotransferase (AST); SGPT, serum glutamic-pyruvic transaminase is now referred to as alanine aminotransferase (ALT). 1 less than 65 g/L, elevated creatinine (Grade 3 greater than 3–6 x upper limit normal range, Grade 4 greater than 6 x ULN), elevated bilirubin (Grade 3 greater than 3–10 x ULN, Grade 4 greater than 10 x ULN), elevated alkaline phosphatase, SGOT or SGPT Adjuvant Treatment of GIST In Study 1, the majority of both Gleevec and placebo-treated patients experienced at least one adverse reaction at some time. The most frequently reported adverse reactions were similar to those reported in other clinical studies in other patient populations and include diarrhea, fatigue, nausea, edema, decreased hemoglobin, rash, vomiting, and abdominal pain. No new adverse reactions were reported in the adjuvant GIST-treatment setting that had not been previously reported in other patient populations, including patients with unresectable and/or malignant metastatic GIST.

Edema, GI disturbances (nausea, vomiting, abdominal distention, and diarrhea), fatigue, low hemoglobin, and rash were the most frequently reported adverse reactions at the time of discontinuation. As in previous trials the most common adverse reactions were diarrhea, fatigue, nausea, edema, decreased hemoglobin, rash, vomiting, and abdominal pain. There were no deaths attributable to Gleevec treatment in either trial.

Table 14: Adverse Reactions Regardless of Relationship to Study Drug Reported in Study 1 (Greater Than or Equal to 5% of Gleevec-Treated Patients) Abbreviations: CTC, common terminology criteria; GIST, gastrointestinal stromal tumors; SGOT, serum glutamic-oxaloacetic transaminase is now referred to as aspartate aminotransferase (AST); SGPT, serum glutamic-pyruvic transaminase is now referred to as alanine aminotransferase (ALT). NCI Common Terminology Criteria for Adverse Events, version 3.0. A patient with multiple occurrences of an adverse reaction is counted only once in the adverse reaction category.: Adverse Reactions Regardless of Relationship to Study Drug by Preferred Term All Grades and 3/4 Grades (Greater Than or Equal to 5% of Gleevec-Treated Patients) Study 2 Abbreviations: AE, adverse event; CTC, common terminology criteria. A patient with multiple occurrences of an adverse reaction is counted only once in the adverse reaction category. 0 0 Adverse Reactions from Multiple Clinical Trials Cardiac Disorders: Estimated 1%-10%: palpitations, pericardial effusion Estimated 0.1%-1%: congestive cardiac failure, tachycardia, pulmonary edema Estimated 0.01%-0.1%: arrhythmia, atrial fibrillation, cardiac arrest, myocardial infarction, angina pectoris Vascular Disorders: Estimated 1%-10%: flushing, hemorrhage Estimated 0.1%-1%: hypertension, hypotension, peripheral coldness, Raynaud’s phenomenon, hematoma, subdural hematoma Investigations: Estimated 1%-10%: blood creatine phosphokinase (CPK) increased, blood amylase increased Estimated 0.1%-1%: blood lactate dehydrogenase (LDH) increased Skin and Subcutaneous Tissue Disorders: Estimated 1%-10%: dry skin, alopecia, face edema, erythema, photosensitivity reaction, nail disorder, purpura Estimated 0.1%-1%: exfoliative dermatitis, bullous eruption, psoriasis, rash pustular, contusion, sweating increased, urticaria, ecchymosis, increased tendency to bruise, hypotrichosis, skin hypopigmentation, skin hyperpigmentation, onychoclasis, folliculitis, petechiae, erythema multiforme, panniculitis (including erythema nodosum) Estimated 0.01%-0.1%: vesicular rash, Stevens-Johnson syndrome, acute generalized exanthematous pustulosis, acute febrile neutrophilic dermatosis (Sweet’s syndrome), nail discoloration, angioneurotic edema, leucocytoclastic vasculitis Gastrointestinal Disorders: Estimated 1%-10%: abdominal distention, gastroesophageal reflux, dry mouth, gastritis Estimated 0.1%-1%: gastric ulcer, stomatitis, mouth ulceration, eructation, melena, esophagitis, ascites, hematemesis, chelitis, dysphagia, pancreatitis Estimated 0.01%-0.1%: colitis, ileus, inflammatory bowel disease General Disorders and Administration-Site Conditions: Estimated 1%-10%: weakness, anasarca, chills Estimated 0.1%-1%: malaise Blood and Lymphatic System Disorders: Estimated 1%-10%: pancytopenia, febrile neutropenia, lymphopenia, eosinophilia Estimated 0.1%-1%: thrombocythemia, bone marrow depression, lymphadenopathy Estimated 0.01%-0.1%: hemolytic anemia, aplastic anemia Hepatobiliary Disorders: Estimated 0.1%-1%: hepatitis, jaundice Estimated 0.01%-0.1%: hepatic failure and hepatic necrosis 1 Immune System Disorders: Estimated 0.01%-0.1%: angioedema Infections and Infestations: Estimated 0.1%-1%: sepsis, herpes simplex, herpes zoster, cellulitis, urinary tract infection, gastroenteritis Estimated 0.01%-0.1%: fungal infection Metabolism and Nutrition Disorders: Estimated 1%-10%: weight decreased, decreased appetite Estimated 0.1%-1%: dehydration, gout, increased appetite, hyperuricemia, hypercalcemia, hyperglycemia, hyponatremia, hyperkalemia, hypomagnesemia Musculoskeletal and Connective Tissue Disorders: Estimated 1%-10%: joint swelling Estimated 0.1%-1%: joint and muscle stiffness, muscular weakness, arthritis Nervous System/Psychiatric Disorders: Estimated 1%-10%: paresthesia, hypesthesia Estimated 0.1%-1%: syncope, peripheral neuropathy, somnolence, migraine, memory impairment, libido decreased, sciatica, restless leg syndrome, tremor Estimated 0.01%-0.1%: increased intracranial pressure 1, confusional state, convulsions, optic neuritis Renal and Urinary Disorders: Estimated 0.1%-1%: renal failure acute, urinary frequency increased, hematuria, renal pain Reproductive System and Breast Disorders: Estimated 0.1%-1%: breast enlargement, menorrhagia, sexual dysfunction, gynecomastia, erectile dysfunction, menstruation irregular, nipple pain, scrotal edema Respiratory, Thoracic and Mediastinal Disorders: Estimated 1%-10%: epistaxis Estimated 0.1%-1%: pleural effusion Estimated 0.01%-0.1%: interstitial pneumonitis, pulmonary fibrosis, pleuritic pain, pulmonary hypertension, pulmonary hemorrhage Endocrine Disorders: Estimated 0.1%-1%: hypothyroidism, hyperthyroidism Eye, Ear, and Labyrinth Disorders: Estimated 1%-10%: conjunctivitis, vision blurred, orbital edema, conjunctival hemorrhage, dry eye Estimated 0.1%-1%: vertigo, tinnitus, eye irritation, eye pain, scleral hemorrhage, retinal hemorrhage, blepharitis, macular edema, hearing loss, cataract Estimated 0.01%-0.1%: papilledema 1, glaucoma 1 Including some fatalities.

Postmarketing Experience

The following additional adverse reactions have been identified during post approval use of Gleevec. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Blood and Lymphatic System Disorders: thrombotic microangiopathy Cardiac Disorders: pericarditis, cardiac tamponade 1 Eye Disorders: vitreous hemorrhage Gastrointestinal Disorders: ileus/intestinal obstruction, tumor hemorrhage/tumor necrosis, GI perforation 1, diverticulitis, gastric antral vascular ectasia Infections: hepatitis B virus reactivation 1 Musculoskeletal and Connective Tissue Disorders: osteonecrosis, rhabdomyolysis/myopathy, growth retardation in children, musculoskeletal pain upon treatment discontinuation (including myalgia, pain in extremity, arthralgia, bone pain), bone marrow edema.

Nervous System Disorders: cerebral edema 1 Reproduction Disorders: hemorrhagic corpus luteum/hemorrhagic ovarian cyst Respiratory, Thoracic and Mediastinal Disorders: acute respiratory failure 1, interstitial lung disease Skin and Subcutaneous Tissue Disorders: lichenoid keratosis, lichen planus, toxic epidermal necrolysis, palmar-plantar erythrodysesthesia syndrome, drug rash with eosinophilia and systemic symptoms (DRESS), pseudoporphyria, pemphigus Vascular Disorders: thrombosis/embolism, anaphylactic shock 1 Including some fatalities.

Agents Inducing CYP3A Metabolism

Concomitant administration of Gleevec and strong CYP3A4 inducers may reduce total exposure of imatinib; consider alternative agents.

Agents Inhibiting CYP3A Metabolism

Concomitant administration of Gleevec and strong CYP3A4 inhibitors may result in a significant imatinib exposure increase. Grapefruit juice may also increase plasma concentrations of imatinib; avoid grapefruit juice.

Interactions With Drugs Metabolized by CYP3A4 Gleevec will increase plasma concentration of CYP3A4 metabolized drugs (e.g., triazolo-benzodiazepines, dihydropyridine calcium channel blockers, certain HMG-CoA reductase inhibitors, etc.). Use caution when administering Gleevec with CYP3A4 substrates that have a narrow therapeutic window. Because warfarin is metabolized by CYP2C9 and CYP3A4, use low-molecular weight or standard heparin instead of warfarin in patients who require anticoagulation.

Interactions With Methotrexate Gleevec may delay the clearance of methotrexate and result in sustained methotrexate concentrations when methotrexate is used at high doses (> 500 mg/m 2 ). Refer to the prescribing information for methotrexate injection for recommendations on management of methotrexate concentrations.

Pregnancy Risk Summary Gleevec can cause fetal harm when administered to a pregnant woman based on human and animal data. There are no clinical studies regarding use of Gleevec in pregnant women. There have been postmarket reports of spontaneous abortions and congenital anomalies from women who have been exposed to Gleevec during pregnancy.

Reproductive studies in rats have demonstrated that imatinib mesylate induced teratogenicity and increased incidence of congenital abnormalities following prenatal exposure to imatinib mesylate at doses equal to the highest recommended human dose of 800 mg/day based on BSA. Advise women to avoid pregnancy when taking Gleevec. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, apprise the patient of the potential hazard to the fetus.

The background risk of major birth defects and miscarriage for the indicated population is not known; however, in the U.S. general population, the estimated background risk of major birth defects of clinically recognized pregnancies is 2% to 4% and of miscarriage is 15% to 20%. Data Animal Data In embryo-fetal development studies in rats and rabbits, pregnant animals received oral doses of imatinib mesylate up to 100 mg/kg/day and 60 mg/kg/day, respectively, during the period of organogenesis. In rats, imatinib mesylate was teratogenic at 100 mg/kg/day (approximately equal to the maximum human dose of 800 mg/day based on BSA), the number of fetuses with encephalocoele and exencephaly was higher than historical control values and these findings were associated with missing or underdeveloped cranial bones.

Lower mean fetal body weights were associated with retarded skeletal ossifications. In rabbits, at doses 1.5 times higher than the maximum human dose of 800 mg/day based on BSA, no effects on the reproductive parameters with respect to implantation sites, number of live fetuses, sex ratio or fetal weight were observed. The examinations of the fetuses did not reveal any drug related morphological changes.

In a pre- and postnatal development study in rats, pregnant rats received oral doses of imatinib mesylate during gestation (organogenesis) and lactation up to 45 mg/kg/day. Five animals developed a red vaginal discharge in the 45 mg/kg/day group on Days 14 or 15 of gestation, the significance of which is unknown since all females produced viable litters and none had increased post-implantation loss. Other maternal effects noted only at the dose of 45 mg/kg/day (approximately one-half the maximum human dose of 800 mg/day based on BSA) included an increased number of stillborn pups and pups dying between postpartum Days 0 and 4.

In the F1 offspring at this same dose level, mean body weights were reduced from birth until terminal sacrifice and the number of litters achieving criterion for preputial separation was slightly decreased. There were no other significant effects in developmental parameters or behavioral testing. F1 fertility was not affected but reproductive effects were noted at 45 mg/kg/day, including an increased number of resorptions and a decreased number of viable fetuses.

The no-observed-effect level (NOEL) for both maternal animals and the F1 generation was 15 mg/kg/day.

Pediatric Use The safety and effectiveness of Gleevec have been demonstrated in pediatric patients with newly diagnosed Ph+ chronic phase CML and Ph+ ALL. There are no data in children under 1 year of age.

Experience with doses greater than 800 mg is limited. Isolated cases of Gleevec overdose have been reported. In the event of overdosage, observe the patient and give appropriate supportive treatment.

Therapy was temporarily interrupted and complete reversal of all abnormalities occurred within 1 week. Treatment was resumed at a dose of 400 mg daily without recurrence of adverse reactions. Another patient developed severe muscle cramps after taking 1,600 mg of Gleevec daily for 6 days.

Complete resolution of muscle cramps occurred following interruption of therapy and treatment was subsequently resumed. Therapy was interrupted, no adverse reactions occurred and the patient resumed therapy. Pediatric Overdose One 3 year old male exposed to a single dose of 400 mg experienced vomiting, diarrhea, and anorexia; and another 3 year old male exposed to a single dose of 980 mg experienced decreased white blood cell (WBC) count and diarrhea.