Description of the active substance:
This information is a reference and it is not enough that the drug has been prescribed by a doctor ..
PHARMACHOLOGIC EFFECT
An antitumor agent of an alkylating action has an imidazotetrazine structure.
In the systemic circulation at physiological values, the pH undergoes a rapid chemical transformation with the formation of the active compound - monomethyltriazenoimidazolecarboxamide (MTIK). It is believed that the cytotoxicity of MTIC is due, first of all, to the alkylation of guanine at the O 6 position and additional alkylation at the N 7 position. Apparently, cytotoxic damage resulting from this, trigger the mechanism of aberrant reduction of the methyl residue.
PHARMACOKINETICS
After oral administration, it is rapidly absorbed from the digestive tract.
C max temozolomide in plasma is achieved on average 0.5-1.5 h (minimum - after 20 min) after taking a single dose.
When taken together with food, a decrease of C max by 33% and AUC decrease by 9% were observed.
Temozolomide quickly penetrates the BBB and enters the cerebrospinal fluid.
Binding to plasma proteins is 10-20%.
T 1/2 from the plasma is approximately 1.8 hours. It is rapidly excreted from the body mainly by the kidneys.
After 24 hours after oral administration, about 5-10% of the dose is determined unchanged in the urine; the remainder is deduced as 4-amino-5-imidazole-carboxamide hydrochloride or unidentified polar metabolites.
INDICATIONS
Malignant gliomas (including multiform glioblastoma, anaplastic astrocytoma) in the presence of relapse or progression of the disease after standard therapy; a common metastatic malignant melanoma (as a first-line therapeutic agent).
DOSING MODE
Individual, depending on age and previous chemotherapy.
SIDE EFFECT
On the part of the digestive system: nausea, vomiting, constipation, anorexia, diarrhea, abdominal pain, indigestion, impaired taste.
From the side of the central nervous system: fatigue, headache, drowsiness, dizziness, paresthesia.
Dermatological reactions: skin rashes, alopecia, skin itching.
From the respiratory system: shortness of breath.
On the part of the hemopoietic system : thrombocytopenia and neutropenia of grade 3 or 4, pancytopenia, leukopenia and anemia.
Other: fever, asthenia, weight loss, malaise, chills.
CONTRAINDICATIONS
Severe myelodepression, pregnancy, lactation (breastfeeding), hypersensitivity to temozolomide or to dacarbazine.
PREGNANCY AND LACTATION
Contraindicated in pregnancy and lactation (breastfeeding).
Men and women of childbearing age should use effective contraceptives during treatment and for at least 6 months after the end of treatment.
APPLICATION FOR CHILDREN
Clinical experience in the use of multiform glioblastoma in children under 3 years of age and with malignant melanoma in children and adolescents under 18 years is absent. Clinical experience with glioma in children older than 3 years is limited.
APPLICATION IN ELDERLY PATIENTS
Use with caution in elderly patients (because in people older than 70 years the risk of developing neutropenia and thrombocytopenia is higher than in younger patients).
SPECIAL INSTRUCTIONS
Use with caution in patients with severe impairment of liver or kidney function, elderly patients (because in people over 70 years, the risk of developing neutropenia and thrombocytopenia is higher than in younger patients).
Clinical experience in the use of multiform glioblastoma in children under 3 years of age and with malignant melanoma in children and adolescents under 18 years is absent. Clinical experience with glioma in children older than 3 years is limited.
Impact on the ability to drive vehicles and manage mechanisms
Temozolomide can cause drowsiness and fatigue and therefore negatively affect the ability to drive vehicles and manage complex mechanisms.
DRUG INTERACTION
With the simultaneous use of temozolomide with valproic acid, a slight but statistically significant decrease in the clearance of temozolomide is observed.
The simultaneous use of temozolomide with other drugs that have a depressing effect on the bone marrow may increase the risk of myelosuppression.
