Anaplastic astrocytoma of brain; Glioblastoma multiforme of brain(newly diagnosed)

Temozolomide is a synthetic oral alkylating agent, and it is rapidly converted at physiologic pH to the active 5-(3-methyltriazen-1-yl)imidazole-4- carboxamide (MTIC). Metabolites of MTIC methylate the O6 position of guanine in DNA, with additional methylation at the N7 position, resulting in cytotoxicity.

Bioavailability is 96~100%, food reduces the rate and extend of absorption; protein binding 14%; elimination half-life: 1.7~2.3 hr, excretion: urine(~38%; parent drug 6%); feces 0.8%

Hypersensitivity to temozolomide or to any of its components

D

unknown/not recommended

Very common(>10%): anorexia, headache, nausea and vomiting, constipation, alopecia, rash, fatigue. Common: Myelosuppression(anemia, thrombocytopenia and leukopenia), depression (13%), insomnia (11%), anxiety (10%), dizziness (8%), convulsions, paresis, amnesia, paresthesia, ataxia, and transient neurologic deterioration, cough

Initial dose: 150 mg/m2/day for 5 days; repeat every 28 days. Subsequent doses of 100-200 mg/m2/day; based upon hematologic tolerance. Capsules should not be opened or chewed but swallowed whole with a glass of water. May be administered on an empty stomach to reduce nausea and vomiting. Bedtime administration may be advised