GLEEVEC dosing for the adjuvant treatment of KIT+ GIST
GLEEVEC® (imatinib mesylate) tablets are indicated for adjuvant treatment of adult patients following complete gross resection of KIT (CD117)-positive GIST.
In clinical trials (Study 2), 1 year of GLEEVEC and 3 years of GLEEVEC were studied. In the patient population defined in Study 2, 3 years of GLEEVEC is recommended. The optimal treatment duration with GLEEVEC is not known.1
Important Safety Considerations
GLEEVEC is often associated with edema and, occasionally, serious fluid retention. Severe fluid retention was reported in 9% to 13.1% of patients taking GLEEVEC for KIT+ GIST. Patients should be weighed and monitored regularly for signs and symptoms of fluid retention, which can be serious or life threatening, and be advised to report any rapid, unexpected weight gain. The probability of edema tended to be increased among older patients (>65 years) or those taking higher doses of GLEEVEC. Severe edema was observed in 182 patients (11.1%). If severe fluid retention occurs, manage with diuretic therapy and withhold GLEEVEC until the event has resolved, and then resume depending on the initial severity of the event.
The recommended starting dose for adjuvant treatment is 400 mg/day
- GLEEVEC may be continued in the absence of progression or unacceptable toxicity1
- There is no treatment restriction based on tumor size1
In the SSG study (Study 2), GLEEVEC 400 mg/day was the dosage for all patients1
Important Safety Considerations
Cytopenias have been reported. Complete blood counts should be performed weekly for the first month, biweekly for the second month, and periodically thereafter as clinically indicated (eg, every 2-3 months). Dose reduction, treatment interruption, or in rare cases discontinuation of treatment may be required for severe neutropenia or thrombocytopenia (see full Prescribing Information for dose adjustment recommendations).
Dose adjustment for hematologic and nonhematologic adverse reactions and hepatoxicity1
- Treatment with GLEEVEC is associated with anemia, neutropenia, and thrombocytopenia. Complete blood counts should be performed weekly for the first month, biweekly for the second month, and periodicially thereafter as clinically indicated
- In some cases, permanent discontinuation may be required
†Absolute neutrophil count (ANC) and platelets are measured in units per µL.
- If elevations in bilirubin >3× institutional upper limit of normal (IULN) or in liver transaminases >5× IULN occur, GLEEVEC should be withheld until bilirubin levels have returned to <1.5× IULN and transaminase levels to <2.5× IULN
- In adults, treatment with GLEEVEC may then be continued at a reduced daily dose
- If severe hepatotoxicity develops, GLEEVEC should be withheld until the event has resolved; if severe fluid retention occurs, manage with diuretic therapy and withhold GLEEVEC until the event has resolved
- Treatment may be resumed depending on the initial severity of the event
1. GLEEVEC® (imatinib mesylate) tablets prescribing information. East Hanover, NJ: Novartis Pharmaceuticals Corporation.
GLEEVEC dosing for the metastatic treatment of KIT+ GIST
GLEEVEC® (imatinib mesylate) tablets are indicated for patients with KIT (CD117)-positive unresectable and/or metastatic malignant gastrointestinal stromal tumors (GIST).
The recommended starting dose of GLEEVEC for adult patients with unresectable and/or metastatic, malignant KIT+ GIST is 400 mg/day1
- 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 reactions1
- Adverse reactions were similar across both dosages in the metastatic trials with the exception of edema and rash/related terms1
- Incidence of both was higher in the 800-mg/day arm vs the 400-mg/day arm (86% vs 77% for edema and 70% vs 56% for rash/related terms)
- Some serious adverse reactions may occur. Please refer to Important Safety Information located at the bottom of this page
1. GLEEVEC® (imatinib mesylate) tablets prescribing information. East Hanover, NJ: Novartis Pharmaceuticals Corporation; January 2012.