Dosage guidance:
Safety: ANC should be ≥1,500/mm3 and platelets ≥100,000/mm3 prior to administration.
Clinical considerations: Temozolomide is associated with a moderate or high emetic potential (Ref); antiemetics are recommended to prevent nausea and vomiting. Pneumocystis jirovecii pneumonia (PCP) prophylaxis is required during concomitant radiation therapy phase for all patients with newly diagnosed glioblastoma; continue PCP prophylaxis in patients who develop lymphocytopenia until lymphocyte recovery to ≤ grade 1. Refer to the protocol or institutional guidance for additional details of off-label dosing.
Anaplastic astrocytoma, newly diagnosed:
Adjuvant therapy (beginning 4 weeks after the completion of radiotherapy):
Cycle 1: Oral, IV: 150 mg/m2 once daily on days 1 to 5 of the 28-day treatment cycle.
Cycles 2 to 6 ( if cycle 1 is tolerated with no or minimal toxicity): Oral, IV: 200 mg/m2 once daily on days 1 to 5 of subsequent 28-day treatment cycles for a total of 6 cycles. If dose was not escalated at the onset of cycle 2, do not increase for cycles 3 to 6.
Concurrent radiation followed by adjuvant therapy (off-label): Oral: 75 mg/m2 once daily for a maximum of 7 weeks during radiation therapy and then (adjuvant therapy; beginning 4 weeks after completion of radiation therapy) 150 mg/m2 once daily for 5 days of a 28-day treatment cycle in cycle 1, followed by 200 mg/m2 once daily for 5 days of subsequent 28-day treatment cycles for up to a total of 12 adjuvant cycles (Ref).
Anaplastic astrocytoma, refractory: Oral, IV: Initial dose: 150 mg/m2 once daily on days 1 to 5 of a 28-day cycle. If ANC ≥1,500/mm3 and platelets ≥100,000/mm3 at the nadir and on day 1 of the next cycle, increase dose to 200 mg/m2 on days 1 to 5 of a 28-day cycle and continue until disease progression or unacceptable toxicity.
Anaplastic oligoastrocytoma or anaplastic oligodendroglioma (off-label use): Oral: 200 mg/m2 once daily on days 1 to 5 of a 28-day treatment cycle for 8 cycles (Ref) or 200 mg/m2 once daily on days 1 to 5 of a 28-day treatment cycle for 6 cycles (Ref) or (in patients with chromosome 1p/19q loss) 150 mg/m2 once daily for 5 days of a 28-day treatment cycle in cycles 1 and 2, followed by 200 mg/m2 once daily for 5 days of subsequent 28-day treatment cycles (Ref) or (in patients without chromosome 1p/19q loss) 150 mg/m2 once daily for 5 days of a 28-day treatment cycle in cycles 1 and 2, followed by 200 mg/m2 once daily for 5 days for up to two 28-day cycles, followed by 75 mg/m2 once daily during radiation therapy, and then followed by post-radiation temozolomide treatment (Ref) or 150 to 200 mg/m2 once daily for 5 days of a 28-day treatment cycle for a maximum of 12 cycles in patients with a complete response or until disease progression in patients with partial response or stable disease (Ref).
Astrocytoma or oligodendroglioma, low grade (off-label use): Oral: 75 mg/m2 once daily during radiation therapy and then (adjuvant therapy) 150 to 200 mg/m2 once daily for 5 days of a 28-day treatment cycle for up to 12 cycles (Ref) or (protracted single-agent therapy) 75 mg/m2 once daily for 21 days of a 28-day treatment cycle for 12 to 15 cycles (Ref).
CNS metastases from solid tumors (off-label use): Oral: 150 mg/m2 (200 mg/m2 in chemotherapy-naïve patients) once daily for 5 days of a 28-day treatment cycle until disease progression or unacceptable toxicity up to a maximum of 1 year (Ref) or 150 mg/m2 (200 mg/m2 in chemotherapy-naïve patients) once daily for 5 days of a 28-day treatment cycle until disease progression or unacceptable toxicity (Ref) or 150 mg/m2 once daily for 5 days of a 28-day treatment cycle until disease progression or unacceptable toxicity (Ref) or 150 mg/m2 once daily on days 1 to 7 and days 15 to 21 of a 28-day or 35-day treatment cycle until disease progression or unacceptable toxicity (Ref) or 150 mg/m2 once daily on days 1 to 7 and days 15 to 21 of a 28-day treatment cycle for a maximum of 2 cycles after complete response, until disease progression or for 4 cycles after stable partial response, 6 cycles after stable disease, or until unacceptable toxicity (Ref).
Cutaneous T-cell lymphoma, mycosis fungoides and Sézary syndrome, advanced (off-label use): Oral: 200 mg/m2 once daily for 5 days every 28 days for up to 1 year (Ref).
Ewing sarcoma, recurrent or progressive (off-label use): Oral: 100 mg/m2 once daily for 5 days every 21 days (in combination with irinotecan) (Ref).
Glioblastoma, newly diagnosed:
Concomitant phase: Oral, IV: 75 mg/m2 once daily for 42 to 49 days (in combination with focal radiotherapy of 60 Gy administered in 30 fractions to the tumor bed or resection site with a 2- to 3-cm margin).
Continue at 75 mg/m2 once daily throughout the concomitant phase as long as ANC ≥1,500/mm3, platelets ≥100,000/mm3, and nonhematologic toxicity ≤ grade 1 (excludes alopecia, nausea/vomiting).
Maintenance phase: Begin 4 weeks after concomitant phase completion.
Cycle 1: Oral, IV: 150 mg/m2 once daily on days 1 to 5 of the 28-day treatment cycle.
Cycles 2 to 6: Oral, IV: May increase to 200 mg/m2 once daily on days 1 to 5; repeat every 28 days for a total of 6 cycles (if ANC ≥1,500/mm3, platelets ≥100,000/mm3, and nonhematologic toxicities for cycle 1 are ≤ grade 2 [excludes alopecia, nausea/vomiting]). If dose was not escalated at the onset of cycle 2, do not increase for cycles 3 to 6.
Duration of therapy: A retrospective analysis of 4 randomized studies in patients with newly diagnosed glioblastoma who were progression free following 6 cycles of adjuvant temozolomide therapy determined that continued administration beyond 6 cycles did not demonstrate improvement in overall survival (Ref). In a randomized study in patients with stable disease after 6 cycles, those randomized to a total of 12 temozolomide cycles had similar progression free and overall survival as the patients who stopped after 6 cycles; however, toxicities, including lymphopenia, thrombocytopenia, and nausea/vomiting, were higher in the patients who continued temozolomide beyond 6 months (Ref).
Glioblastoma, recurrent, relapsed, or progressive (off-label use): Oral: 200 mg/m2 once daily for 5 days every 28 days; if previously treated with chemotherapy, initiate at 150 mg/m2 once daily for 5 days every 28 days and increase to 200 mg/m2 once daily for 5 days every 28 days with cycle 2 if no hematologic toxicity (Ref) or 200 mg/m2 once daily for 5 days every 28 days for up to 9 cycles or until disease progression (Ref) or 150 mg/m2 once daily on days 1 to 7 and days 15 to 21 of a 28-day treatment cycle for a maximum of 12 cycles (Ref) or 50 mg/m2 once daily for a maximum of 12 months or until disease progression (Ref) or 50 mg/m2 once daily until disease progression (Ref).
Melanoma, metastatic malignant (off-label use): Oral: 200 mg/m2 once daily for 5 days every 28 days for up to 12 cycles in the absence of disease progression or unacceptable toxicity. Reduce the dose by 25% in subsequent cycles for grade 3 or 4 hematologic toxicity and reduce the dose by 50% for grade 3 or 4 nonhematologic toxicity (Ref).
Pancreatic neuroendocrine tumors, advanced (off-label use): Oral: 150 mg/m2 once daily for 7 days every 14 days (in combination with bevacizumab) until disease progression or unacceptable toxicity (Ref) or 150 mg/m2 once daily for 7 days every 14 days (in combination with everolimus) for 6 months (Ref) or 150 mg/m2 once daily for 7 days every 14 days (in combination with thalidomide) until disease progression or unacceptable toxicity (Ref) or 200 mg/m2 (maximum dose: 400 mg) once daily on days 10 to 14 (5 days) of a 28-day treatment cycle (in combination with capecitabine) for up to 13 cycles (Ref) or 175 to 200 mg/m2 once daily (at bedtime) on days 10 to 14 (5 days) of a 28-day treatment cycle (in combination with capecitabine) until maximum response, disease progression, or unacceptable toxicity (Ref) or (single-agent therapy) 100 to 150 mg/m2 once daily for 5 days of a 28-day treatment cycle in cycle 1, followed by 100 to 200 mg/m2 once daily for 5 days of subsequent 28-day treatment cycles (Ref).
Primary CNS lymphoma, newly diagnosed (off-label use): Oral: Induction: 150 mg/m2 once daily on days 7 to 11 each month for 5 months (in combination with 14-day cycles of high-dose methotrexate, leucovorin, and rituximab; temozolomide is administered during odd cycles), followed by consolidation therapy with etoposide and cytarabine (Ref).
Primary CNS lymphoma, relapsed or refractory (off-label use): Oral: 150 mg/m2 once daily for 5 days every 28 days, initially in combination with rituximab (for 4 cycles), followed by temozolomide monotherapy: 150 mg/m2 once daily for 5 days every 28 days for 8 cycles (Ref) or 150 mg/m2 once daily on days 1 to 7 and 15 to 21 every 28 days (initially in combination with rituximab for 1 or 2 cycles), followed by temozolomide maintenance monotherapy: 150 mg/m2 once daily for 5 days every 28 days (Ref).
Small cell lung cancer, relapsed/refractory (off-label use): Oral: 75 mg/m2 once daily on days 1 to 21 of a 28-day treatment cycle; continue until disease progression or unacceptable toxicity (Ref).
Soft tissue sarcomas, advanced (off-label use): Oral: 75 to 100 mg/m2 once daily for 6 weeks (Ref).
Soft tissue sarcoma, hemangiopericytoma/solitary fibrous tumor (off-label use): Oral: 150 mg/m2 once daily on days 1 to 7 and days 15 to 21 of a 28-day treatment cycle (in combination with bevacizumab) (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
The renal dosing recommendations are based upon the best available evidence and clinical expertise. Senior Editorial Team: Bruce Mueller, PharmD, FCCP, FASN, FNKF; Jason A. Roberts, PhD, BPharm (Hons), B App Sc, FSHP, FISAC; Michael Heung, MD, MS.
Altered kidney function:
IV, Oral:
CrCl ≥36 mL/minute/m2: No dosage adjustment necessary.
CrCl <36 mL/minute/m2: There are no dosage adjustments provided in the manufacturer's labeling (has not been studied). However, the active alkylating species, methylhydrazine, is not recovered in urine and so no dosage adjustment should theoretically be necessary (Ref). A small retrospective analysis reported that hematologic toxicity in patients with eGFR <36 mL/minute/1.73 m2 is similar to that of patients with normal kidney function (Ref).
Augmented renal clearance (measured urinary CrCl ≥130 mL/minute/1.73 m2):
Note: Augmented renal clearance (ARC) is a condition that occurs in certain critically ill patients without organ dysfunction and with normal SCr concentrations. Young patients (<55 years of age) admitted post-trauma or major surgery are at highest risk for ARC, as well as those with sepsis, burns, or hematologic malignancies. An 8- to 24-hour measured urinary CrCl is necessary to identify these patients (Ref).
IV, Oral: No data available; no dosage adjustment necessary (Ref).
Hemodialysis, intermittent (thrice weekly): Parent drug temozolomide is highly dialyzable (Ref):
IV, Oral: Limited data available; no dosage adjustment necessary. When scheduled dose falls on dialysis days, administer after dialysis (Ref). In one case report, the pharmacokinetics of temozolomide in a patient undergoing hemodialysis were described as similar to those with normal kidney function (Ref). Additionally, acceptable hematologic tolerance was reported in a case series of 6 patients with high-grade gliomas undergoing hemodialysis who were given standard adjuvant doses of temozolomide (Ref). Monitor closely for hematologic toxicities (Ref).
Peritoneal dialysis: Parent drug is likely to be dialyzable (Ref):
IV, Oral: Limited data available; no dosage adjustment necessary (Ref). Monitor closely for hematologic toxicities (Ref).
CRRT: IV, Oral: No data available; no dosage adjustment necessary (Ref).
PIRRT (eg, sustained, low-efficiency diafiltration): IV, Oral: No data available. No dosage adjustment necessary; when scheduled doses falls on PIRRT days, administer after PIRRT (Ref).
Hepatic function impairment prior to treatment initiation:
Mild to moderate impairment (Child-Turcotte-Pugh classes A, B): No dosage adjustment necessary.
Severe impairment (Child-Turcotte-Pugh class C): There are no dosage adjustments provided in the manufacturer's labeling (has not been studied).
American Society of Clinical Oncology guidelines for appropriate systemic therapy dosing in adults with cancer with a BMI ≥30 kg/m2: Utilize patient's actual body weight or calculation of BSA- or weight-based dosing; manage regimen-related toxicities in the same manner as for patients with a BMI <30 kg/m2; if a dose reduction is utilized due to toxicity, may consider resumption of full, weight-based dosing (or previously tolerated dose level) with subsequent cycles only if dose escalations are allowed in the prescribing information, if contributing underlying factors (eg, hepatic or kidney impairment) are sufficiently resolved, AND if performance status has markedly improved or is considered adequate (Ref).
Anaplastic astrocytoma, newly diagnosed:
Monitor CBC on day 22 and then weekly until ANC >1,500/mm3 and platelets>100,000/mm3.
ANC <1,000/mm3, platelets <50,000/mm3, or grade 3 nonhematologic toxicity (excludes alopecia, nausea/vomiting) during previous cycle: Interrupt temozolomide therapy; when ANC >1,500/mm3, platelets >100,000/mm3, and nonhematologic toxicity is resolved to ≤ grade 1, resume temozolomide at a reduced dose for the next cycle. If temozolomide is withheld, decrease dose by 50 mg/m2/day. Discontinue temozolomide for a grade 4 nonhematologic toxicity, for recurrent grade 3 nonhematologic toxicity following a dose reduction, or if unable to tolerate a dose of 100 mg/m2/day.
Anaplastic astrocytoma, refractory:
Monitor CBC on day 22 and then weekly until ANC >1,500/mm3 and platelets >100,000/mm3.
ANC <1,000/mm3 or platelets <50,000/mm3 during any cycle: Reduce temozolomide dose for the next cycle by 50 mg/m2/day. Permanently discontinue temozolomide if unable to tolerate a dose of 100 mg/m2/day.
Glioblastoma, newly diagnosed:
Concomitant phase:
ANC ≥500/mm3 to <1,500/mm3 or platelets ≥10,000/mm3 to <100,000/mm3 or grade 2 nonhematologic toxicity (excludes alopecia, nausea/vomiting): Interrupt temozolomide therapy; resume temozolomide at the same dose when ANC ≥1,500/mm3, platelets ≥100,000/mm3, and nonhematologic toxicity is resolved to ≤ grade 1.
ANC <500/mm3 or platelets <10,000/mm3 or grade 3 or 4 nonhematologic toxicity (excludes alopecia, nausea/vomiting): Discontinue temozolomide therapy.
Maintenance phase:
Monitor CBC on day 22 and then weekly until ANC >1,500/mm3 and platelets>100,000/mm3.
ANC <1,000/mm3, platelets <50,000/mm3, or grade 3 nonhematologic toxicity (excludes alopecia, nausea/vomiting) during previous cycle: Interrupt temozolomide therapy; when ANC >1,500/mm3, platelets >100,000/mm3, and nonhematologic toxicity is resolved to ≤ grade 1, resume temozolomide at a reduced dose for the next cycle. If temozolomide is withheld, decrease dose by 50 mg/m2/day. Discontinue temozolomide for a grade 4 nonhematologic toxicity, for recurrent grade 3 nonhematologic toxicity following a dose reduction, or if unable to tolerate a dose of 100 mg/m2/day.
Glioblastoma, newly diagnosed (off-label dosing): ≥65 years of age:
Concomitant phase: Oral: 75 mg/m2 once daily for 21 consecutive days during radiation therapy (in combination with a reduced radiotherapy total dose of 40.05 Gy administered in 15 daily fractions over 3 weeks) (Ref).
Adjuvant/maintenance therapy: Oral: 150 to 200 mg/m2 once daily for 5 days of each 28-day treatment cycle until disease progression for up to a maximum of 12 cycles (Ref).
Also refer to adult dosing.
(For additional information see "Temozolomide: Pediatric drug information")
Note: Temozolomide is associated with a low or moderate emetic potential depending on dose (Ref); antiemetics may be recommended to prevent nausea and vomiting. Prior to dosing, ANC should be ≥1,500/mm3 and platelets ≥100,000/mm3. Dose, frequency, number of doses, and start date may vary by protocol and treatment phase. Refer to individual protocols.
Ewing sarcoma, recurrent or progressive: Limited data available: Children ≥2 years and Adolescents: Oral: 100 mg/m2/dose once daily for 5 days, repeat cycle every 21 days (in combination with irinotecan; administer 1 hour prior to irinotecan) (Ref); dosing based on a retrospective review.
Neuroblastoma , relapsed or refractory: Limited data available:
Irinotecan regimen: Infants, Children, and Adolescents: Oral: 100 mg/m2/dose once daily for 5 days, repeat cycle every 21 days for up to 6 cycles; in combination with irinotecan; administer 1 hour prior to irinotecan (Ref). Note: Temozolomide doses were rounded to the nearest capsule size.
Topotecan regimen (TOTEM): Infants ≥6 months, Children, and Adolescents: Oral: 150 mg/m2/dose on days 1 to 5 every 28 days; in combination with topotecan; administer prior to the topotecan; continue until disease progression or unacceptable toxicity up to a maximum of 12 months; doses were reduced for hematologic toxicity (Ref).
Single agent: Children ≥3 years and Adolescents: Oral: Administer doses on days 1 to 5 every 21 to 28 days; continue until disease progression or unacceptable toxicity up to a maximum of 24 cycles; doses were reduced by 25% for grade 4 thrombocytopenia or neutropenia, and grade 3 or 4 mucositis, documented sepsis, pulmonary distress/infiltrate, or seizures requiring prophylaxis (Ref).
No prior craniospinal irradiation: Oral: 215 mg/m2/day.
Previous craniospinal irradiation or relapse after bone-marrow transplant: Oral: 180 mg/m2/day.
Solid tumors, relapsed/refractory (including but not limited to brain tumor [astrocytomas, gliomas, medulloblastoma], neuroblastoma, and sarcomas): Limited data available; efficacy results variable: Infants, Children, and Adolescents: Oral: 200 to 215 mg/m2/dose days 1 to 5 every 21 to 28 days; dose was decreased to 180 mg/m2/dose for patients who received prior craniospinal irradiation or relapsed after bone marrow transplant (Ref); in other trials, lower doses of 160 to 200 mg/m2/dose once daily for 5 days every 28 days were used in patients 3 to 18 years of age (Ref).
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no pediatric specific recommendations; refer to individual protocols if available. Based on experience in adult patients with mild to moderate renal impairment, no effect on temozolomide clearance was demonstrated; in severe impairment and dialysis, use with caution; has not been adequately studied.
There are no pediatric specific recommendations; refer to individual protocols if available. Based on experience in adult patients, use with caution; has not been adequately studied.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified. Adverse reactions reported in adults.
>10%:
Cardiovascular: Peripheral edema (11%)
Dermatologic: Alopecia (55%), skin rash (13%)
Gastrointestinal: Anorexia (27%), constipation (22% to 33%), diarrhea (10% to 16%; grades ≥3: 1% to 2%), nausea (49% to 53%; grades ≥3: 1% to 10%), vomiting (29% to 42%; grades ≥3: 2% to 6%)
Hematologic & oncologic: Decreased neutrophils (grades 3/4: 14%), leukopenia (grades 3/4: 11%), lymphocytopenia (grades 3/4: 55%), thrombocytopenia (5%; grades 3/4: 19%)
Infection: Viral infection (11%)
Nervous system: Asthenia (13%), ataxia (11%), dizziness (12%), fatigue (34% to 61%; severe: 13%), headache (23% to 41%; severe: 5%), hemiparesis (18%), seizure (6% to 23%)
Miscellaneous: Fever (13%)
1% to 10%:
Dermatologic: Erythema of skin (<10%), pruritus (<10%), xeroderma (<10%)
Endocrine & metabolic: Hypercorticoidism (<10%), weight gain (<10%)
Gastrointestinal: Abdominal pain (<10%), dysgeusia (<10%), dysphagia (<10%), stomatitis (<10%)
Genitourinary: Mastalgia (females: <10%), urinary frequency (<10%), urinary incontinence (<10%), urinary tract infection (<10%)
Hypersensitivity: Hypersensitivity reaction (<10%)
Nervous system: Abnormal gait (<10%), amnesia (10%), anxiety (<10%), confusion (<10%), depression (<10%), drowsiness (<10%), insomnia (10%), memory impairment (<10%), paresis (<10%), paresthesia (<10%)
Neuromuscular & skeletal: Arthralgia (<10%), back pain (<10%), myalgia (<10%)
Ophthalmic: Blurred vision (<10%), diplopia (<10%), visual disturbance (including visual deficit, vision changes: <10%)
Respiratory: Cough (<10%), dyspnea (<10%), pharyngitis (<10%), sinusitis (<10%), upper respiratory tract infection (<10%)
Frequency not defined: Hematologic & oncologic: Anemia, malignant neoplasm (secondary; including secondary acute myelocytic leukemia), myelodysplastic syndrome
Postmarketing:
Dermatologic: Erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis
Endocrine & metabolic: Diabetes insipidus
Gastrointestinal: Cholestasis
Hematologic & oncologic: Pancytopenia (may be prolonged)
Hepatic: Hepatitis, hepatotoxicity (severe), hyperbilirubinemia, increased liver enzymes
Hypersensitivity: Anaphylaxis
Infection: Opportunistic infection
Local: Injection-site reaction (including erythema at injection site, hematoma at injection site, injection-site pruritus, irritation at injection site, pain at injection site, petechia, swelling at injection site, warm sensation at injection site)
Respiratory: Interstitial pneumonitis, pneumonia due to Pneumocystis jirovecii, pneumonitis, pulmonary alveolitis, pulmonary fibrosis
Serious hypersensitivity to temozolomide or any component of the formulation; serious hypersensitivity to dacarbazine (both temozolomide and dacarbazine are metabolized to 5-[3-methyl-triazene-1-yl]-imidazole-4-carboxamide [MTIC]).
Canadian labeling: Additional contraindications (not in the US labeling): Not recommended in patients with severe myelosuppression.
Concerns related to adverse effects:
• Bone marrow suppression: Myelosuppression (including leukopenia, anemia, and pancytopenia), including fatal outcomes, may occur. In the refractory anaplastic astrocytoma study, myelosuppression usually occurred during the first few therapy cycles and was not typically cumulative; the median platelet nadir onset occurred at 26 days (range: 21 to 40 days) and the median neutrophil nadir onset occurred at 28 days (range: 1 to 44 days). Some patients required hospitalization, blood transfusions, and/or discontinuation due to hematologic toxicity. An increased risk of hematologic toxicity has been reported in older adults and female patients.
• Hepatotoxicity: Hepatotoxicity has been reported; may be severe or fatal. Postmarketing reports of hepatotoxicity have included liver function abnormalities, hepatitis, hepatic failure, cholestasis, hepatitis cholestasis, jaundice, cholelithiasis, hepatic steatosis, hepatic necrosis, hepatic lesion, and hepatic encephalopathy (Sarganas 2012).
• Hypersensitivity: Allergic reactions (including anaphylaxis) have been observed with temozolomide.
• Pneumocystis pneumonia: Pneumocystis jirovecii pneumonia (PCP) has been reported with temozolomide; the risk is increased in those receiving corticosteroids or with longer temozolomide treatment regimens. Provide PCP prophylaxis to all patients with newly diagnosed glioblastoma receiving concomitant phase radiotherapy; continue PCP prophylaxis in patients with lymphopenia until lymphopenia resolves to ≤ grade 1.
• Secondary malignancies: The incidence of secondary malignancies is increased with temozolomide-containing regimens. Cases of myelodysplastic syndromes and secondary malignancies, including myeloid leukemia, have been reported following treatment with temozolomide.
Special populations:
• Older adult: Patients ≥70 years of age experienced a higher incidence of grade 4 neutropenia and thrombocytopenia in cycle 1 (compared to patients <70 years of age).
Dosage form specific issues:
• Polysorbate 80: Some dosage forms may contain polysorbate 80 (also known as Tweens). Hypersensitivity reactions, usually a delayed reaction, have been reported following exposure to pharmaceutical products containing polysorbate 80 in certain individuals (Isaksson 2002; Lucente 2000; Shelley 1995). Thrombocytopenia, ascites, pulmonary deterioration, and renal and hepatic failure have been reported in premature neonates after receiving parenteral products containing polysorbate 80 (Alade 1986; CDC 1984). See manufacturer's labeling.
Other warnings/precautions:
• Administration schedule: Administration schedule (intermittent versus continuous) varies based on indication.
• Temozolomide resistance: Increased O-6-methylguanine-DNA methyltransferase (MGMT) activity/levels within tumor tissue is associated with temozolomide resistance. Glioblastoma patients with decreased levels (due to methylated MGMT promoter) may be more likely to benefit from the combination of radiation therapy and temozolomide (Hegi 2008; Stupp 2009). Determination of MGMT status may be predictive for response to alkylating agents.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Capsule, Oral:
Temodar: 100 mg [DSC]
Temodar: 140 mg [DSC] [contains fd&c blue #2 (indigotine,indigo carmine)]
Temodar: 180 mg [DSC], 250 mg [DSC]
Generic: 5 mg, 20 mg, 100 mg, 140 mg, 180 mg, 250 mg
Solution Reconstituted, Intravenous [preservative free]:
Temodar: 100 mg (1 ea) [pyrogen free; contains polysorbate 80]
May be product dependent
Capsules (Temozolomide Oral)
5 mg (per each): $12.52 - $14.83
20 mg (per each): $50.46 - $57.56
100 mg (per each): $252.29 - $287.76
140 mg (per each): $353.21 - $402.87
180 mg (per each): $454.13 - $517.97
250 mg (per each): $630.91 - $719.60
Solution (reconstituted) (Temodar Intravenous)
100 mg (per each): $1,203.73
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Capsule, Oral:
Temodal: 5 mg [contains fd&c blue #2 (indigotine,indigo carmine)]
Temodal: 20 mg, 100 mg [contains alcohol, usp]
Temodal: 140 mg [contains fd&c blue #2 (indigo carm) aluminum lake]
Temodal: 250 mg [contains alcohol, usp]
Generic: 5 mg, 20 mg, 100 mg, 140 mg, 180 mg, 250 mg
Temozolomide is associated with a moderate or high emetic potential (Ref); antiemetics are recommended to prevent nausea and vomiting.
Oral: Administer at the same time each day. Swallow capsules whole with a glass of water; do not open, chew, or dissolve capsule contents. Administer consistently with respect to food (either consistently fasting or nonfasting). Administer on an empty stomach and/or at bedtime to reduce nausea and vomiting.
Note: In some glioblastoma studies of temozolomide with concurrent radiation therapy, temozolomide was administered in a fasted state, 1 hour prior to radiotherapy (on radiotherapy days), and either in the morning or per institutional protocol on nonradiotherapy days (Ref).
If capsules are accidently opened or damaged, avoid inhalation or contact with skin or mucous membranes; if contact with powder occurs, wash area immediately with water. Follow appropriate hazardous drug handling procedures if capsules must be opened or the contents must be dissolved.
IV: Infuse via an infusion pump over 90 minutes (shorter or longer infusion times may result in suboptimal dosing). Flush line before and after administration. May be administered through the same IV line as sodium chloride 0.9%; do not administer other solutions or medications through the same IV line.
Temozolomide is associated with a low or moderate emetic potential depending on dose (Ref); antiemetics may be recommended to prevent nausea and vomiting.
Oral: Swallow capsule intact with a glass of water; do not chew; per manufacturer's labeling, capsules should not be opened. However, capsules are large and often cannot be swallowed by pediatric patients; if patient is unable to swallow capsule, open capsule and dissolve in acidic juice (eg, orange juice, apple juice) or applesauce, taking precautions to avoid exposure to the cytotoxic agent (Ref); an extemporaneously prepared oral solution or suspension may also be used. Administer temozolomide on an empty stomach or at bedtime to reduce the incidence of nausea and vomiting; absorption is affected by food; may administer with food as long as food intake and administration are performed at the same time each day to ensure consistent bioavailability. Do not repeat if vomiting occurs after dose is administered; wait until the next scheduled dose.
Hazardous agent (NIOSH 2024 [table 1]).
Use appropriate precautions for receiving, handling, storage, preparation, dispensing, transporting, administration, and disposal. Follow NIOSH and USP 800 recommendations and institution-specific policies/procedures for appropriate containment strategy (NIOSH 2023; NIOSH 2024; USP-NF 2020).
Anaplastic astrocytoma, newly diagnosed: Adjuvant treatment of newly diagnosed anaplastic astrocytoma in adults.
Anaplastic astrocytoma, refractory: Treatment of refractory anaplastic astrocytoma in adults.
Glioblastoma, newly diagnosed: Treatment of newly diagnosed glioblastoma in adults (initially in combination with radiotherapy, then as maintenance treatment).
Anaplastic oligoastrocytoma or anaplastic oligodendroglioma; Astrocytoma or oligodendroglioma, low grade; CNS metastases from solid tumors; Cutaneous T-cell lymphomas, mycosis fungoides and Sézary syndrome, advanced; Ewing sarcoma, recurrent or progressive; Glioblastoma, recurrent, relapsed, or progressive; Melanoma, metastatic malignant; Pancreatic neuroendocrine tumors, advanced; Primary CNS lymphoma; Small cell lung cancer, relapsed/refractory; Soft tissue sarcomas, advanced; Soft tissue sarcoma, hemangiopericytoma/solitary fibrous tumor
Temodar may be confused with Tambocor
Temozolomide may be confused with temsirolimus
The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drug classes (chemotherapeutic agent, parenteral and oral) which have a heightened risk of causing significant patient harm when used in error (High-Alert Medications in Acute Care, Community/Ambulatory Care, and Long-Term Care Settings).
None known.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
5-Aminosalicylic Acid Derivatives: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor
Abrocitinib: May increase immunosuppressive effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk X: Avoid
Antithymocyte Globulin (Equine): Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Antithymocyte Globulin (Equine). Specifically, these effects may be unmasked if the dose of cytotoxic chemotherapy is reduced. Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Antithymocyte Globulin (Equine). Specifically, infections may occur with greater severity and/or atypical presentations. Risk C: Monitor
Antithyroid Agents: Myelosuppressive Agents may increase neutropenic effects of Antithyroid Agents. Risk C: Monitor
Baricitinib: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Baricitinib. Risk X: Avoid
BCG Products: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of BCG Products. Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of BCG Products. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Brincidofovir: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Brincidofovir. Risk C: Monitor
Brivudine: May increase adverse/toxic effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk X: Avoid
Chikungunya Vaccine (Live): Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Chikungunya Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Chikungunya Vaccine (Live). Risk X: Avoid
Chloramphenicol (Ophthalmic): May increase adverse/toxic effects of Myelosuppressive Agents. Risk C: Monitor
Chloramphenicol (Systemic): Myelosuppressive Agents may increase myelosuppressive effects of Chloramphenicol (Systemic). Risk X: Avoid
Cladribine: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Cladribine. Risk X: Avoid
CloZAPine: Myelosuppressive Agents may increase adverse/toxic effects of CloZAPine. Specifically, the risk for neutropenia may be increased. Risk C: Monitor
Coccidioides immitis Skin Test: Coadministration of Immunosuppressants (Cytotoxic Chemotherapy) and Coccidioides immitis Skin Test may alter diagnostic results. Management: Consider discontinuing cytotoxic chemotherapy several weeks prior to coccidioides immitis skin antigen testing to increase the likelihood of accurate diagnostic results. Risk D: Consider Therapy Modification
COVID-19 Vaccine (Inactivated Virus): Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of COVID-19 Vaccine (Inactivated Virus). Risk C: Monitor
COVID-19 Vaccine (mRNA): Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of COVID-19 Vaccine (mRNA). Management: Give a 3-dose primary series for all patients aged 6 months and older taking immunosuppressive medications or therapies. Booster doses are recommended for certain age groups. See CDC guidance for details. Risk D: Consider Therapy Modification
COVID-19 Vaccine (Subunit): Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of COVID-19 Vaccine (Subunit). Risk C: Monitor
Deferiprone: Myelosuppressive Agents may increase neutropenic effects of Deferiprone. Management: Avoid the concomitant use of deferiprone and myelosuppressive agents whenever possible. If this combination cannot be avoided, monitor the absolute neutrophil count more closely. Risk D: Consider Therapy Modification
Dengue Tetravalent Vaccine (Live): Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Dengue Tetravalent Vaccine (Live). Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Dengue Tetravalent Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Denosumab: May increase immunosuppressive effects of Immunosuppressants (Cytotoxic Chemotherapy). Management: Consider the risk of serious infections versus the potential benefits of coadministration of denosumab and cytotoxic chemotherapy. If combined, monitor patients for signs/symptoms of serious infections. Risk D: Consider Therapy Modification
Deucravacitinib: May increase immunosuppressive effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk X: Avoid
Etrasimod: May increase immunosuppressive effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk X: Avoid
Fexinidazole: Myelosuppressive Agents may increase myelosuppressive effects of Fexinidazole. Risk X: Avoid
Filgotinib: May increase immunosuppressive effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk X: Avoid
Inebilizumab: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Inebilizumab. Risk C: Monitor
Influenza Virus Vaccines: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Influenza Virus Vaccines. Management: Administer influenza vaccines at least 2 weeks prior to initiating chemotherapy if possible. If vaccination occurs less than 2 weeks prior to or during chemotherapy, revaccinate at least 3 months after therapy discontinued if immune competence restored. Risk D: Consider Therapy Modification
Leflunomide: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Leflunomide. Management: Increase the frequency of chronic monitoring of platelet, white blood cell count, and hemoglobin or hematocrit to monthly, instead of every 6 to 8 weeks, if leflunomide is coadministered with immunosuppressive agents, such as cytotoxic chemotherapy. Risk D: Consider Therapy Modification
Lenograstim: Antineoplastic Agents may decrease therapeutic effects of Lenograstim. Management: Avoid the use of lenograstim 24 hours before until 24 hours after the completion of myelosuppressive cytotoxic chemotherapy. Risk D: Consider Therapy Modification
Linezolid: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor
Lipegfilgrastim: Antineoplastic Agents may decrease therapeutic effects of Lipegfilgrastim. Management: Avoid concomitant use of lipegfilgrastim and myelosuppressive cytotoxic chemotherapy. Lipegfilgrastim should be administered at least 24 hours after the completion of myelosuppressive cytotoxic chemotherapy. Risk D: Consider Therapy Modification
Mumps- Rubella- or Varicella-Containing Live Vaccines: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Mumps- Rubella- or Varicella-Containing Live Vaccines. Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Mumps- Rubella- or Varicella-Containing Live Vaccines. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Nadofaragene Firadenovec: Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Nadofaragene Firadenovec. Specifically, the risk of disseminated adenovirus infection may be increased. Risk X: Avoid
Natalizumab: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Natalizumab. Risk X: Avoid
Ocrelizumab: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Ocrelizumab. Risk C: Monitor
Ofatumumab: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Ofatumumab. Risk C: Monitor
Olaparib: Myelosuppressive Agents may increase myelosuppressive effects of Olaparib. Risk C: Monitor
Palifermin: May increase adverse/toxic effects of Antineoplastic Agents. Specifically, the duration and severity of oral mucositis may be increased. Management: Do not administer palifermin within 24 hours before, during infusion of, or within 24 hours after administration of myelotoxic chemotherapy. Risk D: Consider Therapy Modification
Pidotimod: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Pidotimod. Risk C: Monitor
Pimecrolimus: May increase immunosuppressive effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk X: Avoid
Piperacillin: May increase hypokalemic effects of Antineoplastic Agents. Risk C: Monitor
Pneumococcal Vaccines: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Pneumococcal Vaccines. Risk C: Monitor
Poliovirus Vaccine (Live/Trivalent/Oral): Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Polymethylmethacrylate: Immunosuppressants (Cytotoxic Chemotherapy) may increase hypersensitivity effects of Polymethylmethacrylate. Management: Use caution when considering use of bovine collagen-containing implants such as the polymethylmethacrylate-based Bellafill brand implant in patients who are receiving immunosuppressants. Consider use of additional skin tests prior to administration. Risk D: Consider Therapy Modification
Promazine: May increase myelosuppressive effects of Myelosuppressive Agents. Risk C: Monitor
Rabies Vaccine: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Rabies Vaccine. Management: Complete rabies vaccination at least 2 weeks before initiation of immunosuppressant therapy if possible. If combined, check for rabies antibody titers, and if vaccination is for post exposure prophylaxis, administer a 5th dose of the vaccine. Risk D: Consider Therapy Modification
Ritlecitinib: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Ritlecitinib. Risk X: Avoid
Ropeginterferon Alfa-2b: Myelosuppressive Agents may increase myelosuppressive effects of Ropeginterferon Alfa-2b. Management: Avoid coadministration of ropeginterferon alfa-2b and other myelosuppressive agents. If this combination cannot be avoided, monitor patients for excessive myelosuppressive effects. Risk D: Consider Therapy Modification
Ruxolitinib (Topical): Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Ruxolitinib (Topical). Risk X: Avoid
Sipuleucel-T: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Sipuleucel-T. Management: Consider reducing the dose or discontinuing the use of immunosuppressants, such as cytotoxic chemotherapy, prior to initiating sipuleucel-T therapy. Risk D: Consider Therapy Modification
Sphingosine 1-Phosphate (S1P) Receptor Modulators: May increase immunosuppressive effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk C: Monitor
Tacrolimus (Topical): Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Tacrolimus (Topical). Risk X: Avoid
Talimogene Laherparepvec: Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Talimogene Laherparepvec. Specifically, the risk of infection from the live, attenuated herpes simplex virus contained in talimogene laherparepvec may be increased. Risk X: Avoid
Tertomotide: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Tertomotide. Risk X: Avoid
Tofacitinib: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Tofacitinib. Risk X: Avoid
Typhoid Vaccine: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Typhoid Vaccine. Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Typhoid Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Ublituximab: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Ublituximab. Risk C: Monitor
Upadacitinib: Immunosuppressants (Cytotoxic Chemotherapy) may increase immunosuppressive effects of Upadacitinib. Risk X: Avoid
Vaccines (Live): Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Vaccines (Live). Specifically, the risk of vaccine-associated infection may be increased. Vaccines (Live) may decrease therapeutic effects of Immunosuppressants (Cytotoxic Chemotherapy). Risk X: Avoid
Vaccines (Non-Live/Inactivated/Non-Replicating): Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Vaccines (Non-Live/Inactivated/Non-Replicating). Management: Give non-live/inactivated/non-replicating vaccines at least 2 weeks prior to starting chemotherapy when possible. Patients vaccinated less than 14 days before or during chemotherapy should be revaccinated at least 3 months after therapy is complete. Risk D: Consider Therapy Modification
Valproic Acid and Derivatives: May increase adverse/toxic effects of Temozolomide. Valproic Acid and Derivatives may increase serum concentration of Temozolomide. Risk C: Monitor
Yellow Fever Vaccine: Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Yellow Fever Vaccine. Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Yellow Fever Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Zoster Vaccine (Live/Attenuated): Immunosuppressants (Cytotoxic Chemotherapy) may increase adverse/toxic effects of Zoster Vaccine (Live/Attenuated). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Cytotoxic Chemotherapy) may decrease therapeutic effects of Zoster Vaccine (Live/Attenuated). Risk X: Avoid
Food reduces rate and extent of absorption. Management: Administer consistently either with food or without food (was administered in studies under fasting and nonfasting conditions).
Evaluate pregnancy status prior to use in patients who could become pregnant. Patients who could become pregnant should use effective contraception during treatment and for 6 months after the last temozolomide dose. Patients with partners who are pregnant or could become pregnant should use condoms during treatment and for 3 months after the last temozolomide dose.
Males should not donate semen during treatment and for 3 months after the last temozolomide dose.
Temozolomide may impair fertility; limited data indicate changes in sperm parameters during temozolomide treatment; however, there is no information in duration or reversibility of sperm changes.
Based on the mechanism of action and findings in animal reproduction studies, in utero exposure to temozolomide may cause fetal harm.
It is not known if temozolomide is present in breast milk.
Due to the potential for serious adverse reactions (including myelosuppression) in the breastfed infant, breastfeeding is not recommended by the manufacturer during treatment and for 1 week after the last temozolomide dose.
Monitor CBC with differential and platelets prior to treatment initiation, weekly during the concomitant phase with radiation therapy (and as clinically indicated), and on days 1 and 22 during each 28-day treatment cycle, as well as weekly, until hematologic recovery for ANC <1,500/mm3 and platelets <100,000/mm3; may require more frequent monitoring if myelosuppression occurs. Monitor LFTs at baseline, halfway through the first cycle, prior to each subsequent cycle, and at ~2 to 4 weeks after the last temozolomide dose. Evaluate pregnancy status prior to use (in patients who could become pregnant). Monitor for lymphopenia and for signs/symptoms of Pneumocystis jirovecii pneumonia, hepatotoxicity, hypersensitivity, and secondary malignancies. Monitor adherence.
The American Society of Clinical Oncology hepatitis B virus (HBV) screening and management provisional clinical opinion (ASCO [Hwang 2020]) recommends HBV screening with hepatitis B surface antigen, hepatitis B core antibody, total Ig or IgG, and antibody to hepatitis B surface antigen prior to beginning (or at the beginning of) systemic anticancer therapy; do not delay treatment for screening/results. Detection of chronic or past HBV infection requires a risk assessment to determine antiviral prophylaxis requirements, monitoring, and follow-up.
Temozolomide is a prodrug which is rapidly and nonenzymatically converted to the active alkylating metabolite MTIC [(methyl-triazene-1-yl)-imidazole-4-carboxamide]; this conversion is spontaneous, nonenzymatic, and occurs under physiologic conditions in all tissues to which it distributes (Marchesi 2007; Villano 2009). The cytotoxic effects of MTIC are manifested through alkylation (methylation) of DNA at the O6, N7 guanine positions which lead to DNA double strand breaks and apoptosis (Villano 2009). Temozolomide is noncell cycle specific (Marchesi 2007).
Absorption: Oral: Rapid and complete.
Distribution: Vd: Parent drug: 0.4 L/kg. Temozolomide penetrates blood-brain barrier; cerebrospinal fluid levels are ~35% to 39% of plasma levels (Yung 1999).
Protein binding: 15%.
Metabolism: Prodrug, hydrolyzed to the active form, 5-(3-methyl-triazene-1-yl)-imidazole-4-carboxamide (MTIC); MTIC is eventually eliminated as CO2 and 5-aminoimidazole-4-carboxamide (AIC), a natural constituent in urine; CYP isoenzymes play only a minor role in metabolism (of temozolomide and MTIC).
Bioavailability: Oral: 100% (on a mg-per-mg basis, IV temozolomide, infused over 90 minutes, is bioequivalent to an oral dose).
Half-life elimination: Mean: Parent drug: Children: 1.7 hours; Adults: 1.8 hours.
Time to peak: Oral: Median: 1 hour; with food (high-fat meal): 2.25 hours.
Excretion: Urine (~38%; parent drug 6%; AIC 12%); feces <1%.
Clearance: ~5.5 L/hour/m2; pediatric subjects 3 to 17 years have similar temozolomide clearance as adults.
Sex: Females may have an ~5% lower temozolomide clearance (adjusted for body surface area) than males.