CARMNU

Indications

• Recurrent glioblastoma multiforme
• High-grade malignant glioma
• Multiple myeloma
• Hodgkin's disease
• Non-Hodgkin's lymphoma

Dosage

Children: Refer

Adults: Refer to product literature for specific dosing information, especially considering individual patient characteristics such as renal function.

Mechanism of action

Carmustine causes cross-links in DNA and RNA, inhibiting DNA synthesis, RNA production, and protein synthesis. It also carbamoylates glutathione reductase, leading to cell death. This drug is known to produce O6-methylguanine, which triggers DNA mismatch repair, resulting in apoptosis and senescence. Carmustine, along with temozolomide, impacts nuclear organization and chromatin structure, inducing clustering of heterochromatin regions and altering histone modifications.

Pharmacodynamics

As a nitrosourea, carmustine is indicated for palliative therapy in brain tumors, multiple myeloma, Hodgkin's disease, and non-Hodgkin's lymphomas. It is characterized by its ability to alkylate DNA and RNA, leading to cytotoxic effects. Unlike other alkylators, carmustine is not cross-resistant, and may inhibit various enzymatic processes through the carbamoylation of amino acids in proteins, contributing to its unique therapeutic profile.

Pharmacokinetics

Carmustine is administered intravenously or via implant and is subject to considerable hepatic metabolism. The drug is highly lipophilic, allowing it to cross the blood-brain barrier effectively, which is particularly beneficial in treating brain tumors. The pharmacokinetics involve a significant distribution phase, with a half-life that may vary based on the administration route. Its clearance is primarily through hepatic pathways, and renal function should be monitored due to potential nephrotoxicity.

Contra-indications

• Hypersensitivity to carmustine or any component of the formulation
• Acute porphyrias
• Severe bone marrow disorders
• Active infections

Adverse effects

• Alopecia
• Anaemia
• Ataxia
• Constipation
• Diarrhoea
• Dizziness
• Headache
• Nausea
• Seizures
• Vomiting
• Capillary leak syndrome
• Delirium
• Encephalopathy
• Hallucinations
• Hypoxia
• Intracranial pressure increase
• Lung toxicity
• Secondary malignancy
• Pulmonary fibrosis
• Nephrotoxicity
• Gynaecomastia
• Hypogonadism
• Ovarian failure
• Diabetes mellitus
• Myasthenia gravis

Interactions

• Other alkylating agents may have additive effects
• May interact with medications that affect bone marrow function
• Increased risk of toxicity when used with other cytotoxic agents

Precautions

• Monitor for signs of infection due to increased risk
• Caution in patients with hepatic impairment
• Use with caution in patients with renal impairment
• Caution in patients with cardiovascular disease due to potential for hypertension and hypotension
• Frequent blood tests are necessary due to risk of myelosuppression

Pregnancy

Carmustine is classified as a category D drug. It is not recommended during pregnancy due to potential harm to the fetus.

Breast-feeding

Carmustine is contraindicated during breastfeeding. Discontinue breastfeeding if treatment is necessary.

Storage

Store in a cool, dry place away from light. Protect from moisture and heat. Follow specific storage instructions as per the product literature.

Formulations

• Injectable form (intravenous)
• Implantable form
• Oral capsules
• Oral solution

Mechanism of action

Carmustine causes cross-links in DNA and RNA, leading to the inhibition of DNA synthesis, RNA production and RNA translation (protein synthesis). Carmustine also binds to and modifies (carbamoylates) glutathione reductase. This leads to cell death. Temozolomide (TMZ) and carmustine (BCNU), cancer-drugs usually used in the treatment of gliomas, are DNA-methylating agents producing O6-methylguanine. It has been shown that 06-methylguanine triggers DNA mismatch repair and in turn induce apoptosis and senescence, respectively, over a 4 and 6 days period. Temozolomide and carmustine have an earlier effect on nuclear organization and chromatin structure. In particular, temozolomideZ and carmustine induce clustering of pericentromeric heterochromatin regions and increase the amount of heterochromatic proteins MeCP2 and HP1alpha bound to chromatin. These drugs also decrease global levels of histone H3 acetylation and increase levels of histone H3 trimethylated on lysine 9 (H3-triMeK9). These events precede the senescence status. ... Temozolomide and carmustine efficacy in glioma treatment may implicate a first event characterized by changes in heterochromatin organization and its silencing which is then followed by apoptosis and senescence. Although carmustine is believed to act by alkylation of DNA and RNA, the mechanism of action has not been completely elucidated and other effects such as carbamoylation and modification of cellular proteins may be involved. The overall result is thought to be the inhibition of both DNA and RNA synthesis.

Pharmacodynamics

Carmustine is one of the nitrosoureas indicated as palliative therapy as a single agent or in established combination therapy with other approved chemotherapeutic agents in treatment of brain tumors, multiple myeloma, Hodgkin's disease, and non-Hodgkin's lymphomas. Although it is generally agreed that carmustine alkylates DNA and RNA, it is not cross resistant with other alkylators. As with other nitrosoureas, it may also inhibit several key enzymatic processes by carbamoylation of amino acids in proteins.