Glioblastoma multiforme

Active Ingredient: Temozolomide

Indication for Temozolomide

Population group: only adults (18 years old or older)

Temozolomide is indicated for the treatment of adult patients with newly-diagnosed glioblastoma multiforme concomitantly with radiotherapy (RT) and subsequently as monotherapy treatment.

For this indication, competent medicine agencies globally authorize below treatments:

75-200 mg/m² once daily

Route of admnistration

Intravenous

Defined daily dose

75 - 200 mg per m² of body surface area (BSA)

Dosage regimen

From 75 To 200 mg per m² of body surface area (BSA) once every day

Detailed description

Adult patients with newly-diagnosed glioblastoma multiforme

Temozolomide is administered in combination with focal radiotherapy (concomitant phase) followed by up to 6 cycles of temozolomide (TMZ) monotherapy (monotherapy phase).

Concomitant phase

Temozolomide is administered orally at a dose of 75 mg/m² daily for 42 days concomitant with focal radiotherapy (60 Gy administered in 30 fractions). No dose reductions are recommended, but delay or discontinuation of temozolomide administration should be decided weekly according to haematological and non-haematological toxicity criteria. Temozolomide administration can be continued throughout the 42 day concomitant period (up to 49 days) if all of the following conditions are met:

  • absolute neutrophil count (ANC) ≥1.5 × 109/l
  • thrombocyte count ≥100 × 109/l
  • common toxicity criteria (CTC) non-haematological toxicity ≤Grade 1 (except for alopecia, nausea and vomiting).

During treatment a complete blood count should be obtained weekly. Temozolomide administration should be temporarily interrupted or permanently discontinued during the concomitant phase according to the haematological and non-haematological toxicity criteria as noted in Table 1.

Table 1. Temozolomide dosing interruption or discontinuation during concomitant radiotherapy and temozolomide:

ToxicityTemozolomide interruptionaTemozolomide discontinuation
Absolute neutrophil count≥0.5 and <1.5 × 109/l<0.5 × 109/l
Thrombocyte count≥10 and <100 × 109/l<10 × 109/l
CTC non-haematological toxicity (except for alopecia, nausea, vomiting)CTC Grade 2CTC Grade 3 or 4

a Treatment with concomitant temozolomide can be continued when all of the following conditions are met: absolute neutrophil count ≥1.5 × 109/l; thrombocyte count ≥100 × 109/l; CTC non-haematological toxicity ≤Grade 1 (except for alopecia,
nausea, vomiting).

Monotherapy phase

Four weeks after completing the temozolomide + RT concomitant phase, temozolomide is administered for up to 6 cycles of monotherapy treatment. Dose in Cycle 1 (monotherapy) is 150 mg/m² once daily for 5 days followed by 23 days without treatment. At the start of Cycle 2, the dose is escalated to 200 mg/m² if the CTC non-haematological toxicity for Cycle 1 is Grade ≤2 (except for alopecia, nausea and vomiting), absolute neutrophil count (ANC) is ≥1.5 × 109/l, and the thrombocyte count is ≥100 × 109/l. If the dose was not escalated at Cycle 2, escalation should not be done in subsequent cycles. Once escalated, the dose remains at 200 mg/m² per day for the first 5 days of each subsequent cycle except if toxicity occurs. Dose reductions and discontinuations during the monotherapy phase should be applied according to Tables 2 and 3.

During treatment a complete blood count should be obtained on Day 22 (21 days after the first dose of temozolomide). The dose should be reduced or administration discontinued according to Table 3.

Table 2. Temozolomide dose levels for monotherapy treatment:

Dose levelTemozolomide dose (mg/m²/day)Remarks
–1100Reduction for prior toxicity
0150Dose during Cycle 1
1200Dose during Cycles 2-6 in absence of toxicity

Table 3. Temozolomide dose reduction or discontinuation during monotherapy treatment:

ToxicityReduce temozolomide by 1 dose levelaDiscontinue temozolomide
Absolute neutrophil count<1.0 × 109/lSee footnote b
Thrombocyte count<50 × 109/lSee footnote b
CTC non-haematological Toxicity (except for alopecia, nausea, vomiting)CTC Grade 3CTC Grade 4b

a Temozolomide dose levels are listed in Table 2.
b Temozolomide is to be discontinued if:

  • dose level -1 (100 mg/m²) still results in unacceptable toxicity
  • the same Grade 3 non-haematological toxicity (except for alopecia, nausea, vomiting) recurs after dose reduction.

Dosage considerations

The appropriate dose of temozolomide should be infused intravenously using a pump over a period of 90 minutes.

75-200 mg/m² once daily

Route of admnistration

Oral

Defined daily dose

75 - 200 mg per m² of body surface area (BSA)

Dosage regimen

From 75 To 200 mg per m² of body surface area (BSA) once every day

Detailed description

Adult patients with newly-diagnosed glioblastoma multiforme

Temozolomide is administered in combination with focal radiotherapy (concomitant phase) followed by up to 6 cycles of temozolomide (TMZ) monotherapy (monotherapy phase).

Concomitant phase

Temozolomide is administered orally at a dose of 75 mg/m² daily for 42 days concomitant with focal radiotherapy (60 Gy administered in 30 fractions). No dose reductions are recommended, but delay or discontinuation of temozolomide administration should be decided weekly according to haematological and non-haematological toxicity criteria. Temozolomide administration can be continued throughout the 42 day concomitant period (up to 49 days) if all of the following conditions are met:

  • absolute neutrophil count (ANC) ≥1.5 × 109/l
  • thrombocyte count ≥100 × 109/l
  • common toxicity criteria (CTC) non-haematological toxicity ≤Grade 1 (except for alopecia, nausea and vomiting).

During treatment a complete blood count should be obtained weekly. Temozolomide administration should be temporarily interrupted or permanently discontinued during the concomitant phase according to the haematological and non-haematological toxicity criteria as noted in Table 1.

Table 1. Temozolomide dosing interruption or discontinuation during concomitant radiotherapy and temozolomide:

ToxicityTemozolomide interruptionaTemozolomide discontinuation
Absolute neutrophil count≥0.5 and <1.5 × 109/l<0.5 × 109/l
Thrombocyte count≥10 and <100 × 109/l<10 × 109/l
CTC non-haematological toxicity (except for alopecia, nausea, vomiting)CTC Grade 2CTC Grade 3 or 4

a Treatment with concomitant temozolomide can be continued when all of the following conditions are met: absolute neutrophil count ≥1.5 × 109/l; thrombocyte count ≥100 × 109/l; CTC non-haematological toxicity ≤Grade 1 (except for alopecia,
nausea, vomiting).

Monotherapy phase

Four weeks after completing the temozolomide + RT concomitant phase, temozolomide is administered for up to 6 cycles of monotherapy treatment. Dose in Cycle 1 (monotherapy) is 150 mg/m² once daily for 5 days followed by 23 days without treatment. At the start of Cycle 2, the dose is escalated to 200 mg/m² if the CTC non-haematological toxicity for Cycle 1 is Grade ≤2 (except for alopecia, nausea and vomiting), absolute neutrophil count (ANC) is ≥1.5 × 109/l, and the thrombocyte count is ≥100 × 109/l. If the dose was not escalated at Cycle 2, escalation should not be done in subsequent cycles. Once escalated, the dose remains at 200 mg/m² per day for the first 5 days of each subsequent cycle except if toxicity occurs. Dose reductions and discontinuations during the monotherapy phase should be applied according to Tables 2 and 3.

During treatment a complete blood count should be obtained on Day 22 (21 days after the first dose of temozolomide). The dose should be reduced or administration discontinued according to Table 3.

Table 2. Temozolomide dose levels for monotherapy treatment:

Dose levelTemozolomide dose (mg/m²/day)Remarks
–1100Reduction for prior toxicity
0150Dose during Cycle 1
1200Dose during Cycles 2-6 in absence of toxicity

Table 3. Temozolomide dose reduction or discontinuation during monotherapy treatment:

ToxicityReduce temozolomide by 1 dose levelaDiscontinue temozolomide
Absolute neutrophil count<1.0 × 109/lSee footnoteb
Thrombocyte count<50 × 109/lSee footnoteb
CTC non-haematological Toxicity (except for alopecia, nausea, vomiting)CTC Grade 3CTC Grade 4b

a Temozolomide dose levels are listed in Table 2.
b Temozolomide is to be discontinued if:

  • dose level -1 (100 mg/m²) still results in unacceptable toxicity
  • the same Grade 3 non-haematological toxicity (except for alopecia, nausea, vomiting) recurs after dose reduction.

Dosage considerations

The appropriate dose of temozolomide should be infused intravenously using a pump over a period of 90 minutes.

Active ingredient

Temozolomide

Temozolomide is a triazene, which undergoes rapid chemical conversion at physiologic pH to the active monomethyl triazenoimidazole carboxamide (MTIC). The cytotoxicity of MTIC is thought to be due primarily to alkylation at the O6 position of guanine with additional alkylation also occurring at the N7 position. Cytotoxic lesions that develop subsequently are thought to involve aberrant repair of the methyl adduct.

Read more about Temozolomide

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