Vinblastine

Vinblastine is a drug that is used in medical practice to treat various types of cancer. It belongs to the class of antitumor (cytotoxic) drugs and is used in chemotherapy. Vinblastine is a member of the group of antimitotic drugs, which have their effect by inhibiting the division of cancer cells.

Indications Vinblastine

Vinblastine is used to treat different types of cancer. It is usually used in combination with other anticancer drugs as part of chemotherapy regimens. Here are some of the main indications for the use of vinblastine:

1. Lymphomas: Vinblastine is used to treat various types of lymphomas, including lymphogranulomatosis (Hodgkin's disease) and non-Hodgkin's lymphomas.
2. Bladder Cancer: It can be included in chemotherapy regimens for bladder cancer.
3. Breast Cancer: Vinblastine is sometimes used in chemotherapy protocols to treat breast cancer, especially when the cancer has spread to the lymph nodes.
4. Ovarian Cancer: It can be included in chemotherapy regimens for the treatment of ovarian cancer, both in the initial and advanced stages.
5. Cervical Cancer: In some cases, vinblastine may be used in chemotherapy to treat cervical cancer, especially when the cancer has spread beyond the uterus.
6. Other cancers: Vinblastine can also be used to treat other cancers such as stomach cancer, lung cancer, bone cancer, and others.

Indications for the use of vinblastine are determined by the doctor depending on the type and stage of cancer, as well as the general condition of the patient

Release form

Vinblastine is usually supplied as a powder to prepare a solution for injection. This powder is a white or almost white powder that is dissolved in a special solvent before it is injected into the body.

Once the vinblastine solution is prepared, it is usually administered intravenously (through a vein) under the supervision of medical personnel to ensure the correct dosage and to monitor the patient for side effects.

Pharmacodynamics

The mechanism of action of vinblastine relates to its ability to prevent tumor cell division by interacting with microtubules in cells.

Highlights of the pharmacodynamics of vinblastine include the following:

1. Inhibition of mitosis: Vinblastine interferes with the normal function of microtubules, structural components of the cell that are necessary for the proper separation and movement of chromosomes during mitosis (cell division). It binds to the end of microtubules, causing them to malfunction.
2. Interruption of the cell cycle: As a result of disruption of microtubule function, vinblastine stops the process of mitosis and cell division, leading to a halt in tumor growth and development.
3. Action on cell organelles: Vinblastine can also affect other structures within the cell such as the Golgi apparatus, endoplasmic reticulum and nucleus membranes, which also helps to slow cell division and reduce tumor growth.

It is important to note that vinblastine acts nonspecifically on actively dividing cells, meaning that it mainly affects tumor cells, but can also affect some normal rapidly dividing cells such as bone marrow and intestinal mucosa, which can cause side effects associated with a decrease in their numbers.

Pharmacokinetics

The pharmacokinetics of vinblastine describes its absorption, distribution, metabolism, and excretion from the body, which is important for optimizing dosing regimens and minimizing side effects.

Absorption

Vinblastine is usually administered intravenously, which ensures its 100% bioavailability. Oral administration of vinblastine is ineffective due to its low bioavailability and significant primary metabolism in the liver (first-pass effect).

Distribution

After administration, vinblastine is rapidly distributed in the tissues of the body. It has a high degree of binding to blood plasma proteins (mainly albumin), which is more than 80%. Vinblastine is able to penetrate into many tissues and body fluids, including cerebrospinal fluid, although the concentration in cerebrospinal fluid is much lower than in blood plasma.

Metabolism

Vinblastine is metabolized in the liver with the participation of cytochrome P450 enzymes. The main pathway of metabolism is demethylation. Vinblastine metabolites may be active and contribute to both the therapeutic effect and toxicity of the drug.

Withdrawal

Vinblastine and its metabolites are eliminated from the body mainly with bile in the feces. A small portion may be excreted by the kidneys with urine. The elimination half-life of vinblastine from blood plasma ranges from 20 to 85 hours, indicating significant variability between patients.

Features

• The pharmacokinetics of vinblastine may vary significantly between different patients due to individual differences in metabolic rate and liver function.
• Side effects of vinblastine may include myelosuppression (suppression of bone marrow hematopoiesis), neuropathy, loss of appetite, alopecia (hair loss), and others. Understanding pharmacokinetics helps in adapting dosage to minimize these effects.

Dosing and administration

Vinblastine is usually used as an injection that is given into a vein (intravenously). The method of administration and dosage of vinblastine may vary depending on the type of tumor, stage of disease, general condition of the patient, and other factors. Typically, vinblastine doses are set by an oncologist or other chemotherapy specialist and should be strictly adhered to.

Examples of standard vinblastine dosing regimens may include the following:

1. Lymphomas (Hodgkin's disease and non-Hodgkin's lymphoma):

   • Can be used in combination with other anticancer drugs.
   • Typical adult dose: 6-10 mg/m² body surface area, usually once every 7-14 days.

2. Bladder cancer:

   • May be used in combination with other drugs such as cisplatin or gemcitabine.
   • Typical adult dose: 0.15-0.2 mg/kg body weight, once every 21 days.

3. Breast cancer:

   • It can be used in combination with other anticancer drugs such as cyclophosphamide and doxorubicin.
   • Typical adult dose: 1.5 mg/m² body surface area, usually once every 14 days.

4. Ovarian cancer:

   • May be used in combination with other chemotherapeutic agents such as cisplatin or doxorubicin.
   • Typical adult dose: 0.5-1.4 mg/m² body surface area, usually once every 7-14 days.

The dosage and schedule of vinblastine may be adjusted according to treatment response and toxicity.

Use Vinblastine during pregnancy

The use of vinblastine during pregnancy is highly undesirable and may be harmful to fetal development. Vinblastine is FDA Category D for use during pregnancy, which means that there is evidence of risk to the fetus based on animal studies and/or human data, but the potential benefits of using the drug in pregnancy may be justified in some cases under strict surveillance and risk-benefit assessment.

The following risks may be associated with the use of vinblastine during pregnancy:

1. Fetal Toxicity: Vinblastine may penetrate the placental barrier and have toxic effects on the developing fetus, which may result in health and developmental risks.
2. Birth defects: There is a risk of congenital anomalies and developmental defects in the fetus when vinblastine is used during pregnancy.
3. Maternal risk: Vinblastine may also have adverse effects on maternal health, including possible side effects and health risks.

If vinblastine is to be used in a pregnant woman, the decision to prescribe it should be made by the physician after careful discussion with the patient. The physician should weigh the potential risks to the fetus and mother and assess the benefits of vinblastine based on the specific clinical situation.

Contraindications

Like any medical drug, Vinblastine has its own contraindications. Here are some of them:

1. Allergic Reaction: People with a known allergy to Vinblastine or to any other vincristine-containing drugs should avoid its use.
2. Hypersensitivity to vincalkaloids: This includes a history of intolerance or toxic reaction to other vincristine-containing drugs such as vincristine and vinorelbine.
3. Pregnancy and breastfeeding: Vinblastine may be dangerous for the fetus and is contraindicated in pregnancy. It is also not recommended to take Vinblastine during breastfeeding.
4. Serious hepatic impairment: In patients with serious hepatic impairment, the metabolism and excretion of Vinblastine may be impaired, which may result in an increased risk of toxicity.
5. Neutropenia: The drug may aggravate neutropenia (decreased levels of neutrophils in the blood), which may lead to an increased risk of infections.
6. Hematopoietic disorders: Vinblastine may cause a decrease in the number of platelets and red blood cells, which can cause bleeding and anemia.
7. Renal impairment: In patients with impaired renal function, Vinblastine dose adjustment or complete avoidance may be required.
8. Neuropathy: In patients withneuropathy, especially severe neuropathy, the use of Vinblastine may lead to further deterioration of the condition.

Side effects Vinblastine

Vinblastine, like many chemotherapy drugs, can cause a variety of side effects. Some of these include:

1. Decreased blood cell count: Vinblastine may decrease the number of white blood cells, platelets, and red blood cells, which can lead to an increased risk of infections, bleeding, and anemia.
2. Neuropathy: This is a condition in which peripheral nerves are damaged, which can lead to numbness, tingling, or pain in the arms and legs.
3. Hair loss: Vinblastine can cause hair loss. Hair usually starts to grow back after treatment is completed.
4. Muscle pain and weakness: Some patients may experience muscle pain and general weakness.
5. Flatulenceand diarrhea: Some patients may experience stomach problems such as flatulence and diarrhea.
6. Nausea and vomiting: These are common side effects of chemotherapy, including Vinblastine. Your doctor may prescribe anti-nausea medications to reduce these symptoms.
7. Osteoporosis: Long-term use of Vinblastine may cause osteoporosis, which increases the risk of fractures.
8. Hepatotoxicity: Some patients may develop liver damage.
9. Injectionsite reactions: In case of intravenous injection of Vinblastine, irritation and inflammation at the injection site may occur.

Overdose

An overdose of Vinblastine can be dangerous and may cause serious side effects. As with any medication, it is important to follow the dosage prescribed by your doctor. The following symptoms and complications may occur if you overdose on Vinblastine:

1. Blood Toxic Effects: Overdose may increase the toxic effects of Vinblastine on hematopoiesis, resulting in decreased numbers of white blood cells, platelets, and red blood cells.
2. Neurotoxic effects: Increased neurotoxicity, including severe neuropathy, may result from overdose.
3. Severe nausea and vomiting: Overdose may increase symptoms of nausea and vomiting, which may lead to dehydration and electrolyte imbalance.
4. Serious liver and kidney side effects: Overdose may cause liver and kidney damage.
5. General deterioration of the patient's condition: Depending on the degree of overdose and individual characteristics of the patient's body, serious complications may develop, up to life-threatening.

In case of suspected Vinblastine overdose, medical attention should be sought immediately. Physicians can take appropriate measures to minimize the effects of overdose, including symptomatic therapy, maintenance of water-electrolyte balance and monitoring of organ function.

Interactions with other drugs

Vinblastine may interact with various other drugs, which may alter their effectiveness or increase the risk of side effects. Below are some known interactions between Vinblastine and other drugs:

1. Myelosuppressive drugs: Drugs such as other cytostatics or drugs for the treatment of Graves' disease (e.g. Thyrotropics) may increase the myelosuppressive effects of Vinblastine, which may result in an increased decrease in the number of hematopoietic cells.
2. Drugs causing neurotoxicity: Some drugs, such as other vincalkaloids or neuroleptics, may increase the risk of neurotoxicity when used concomitantly with Vinblastine.
3. Drugs thatincrease nausea and vomiting: Drugs that cause nausea and vomiting (antibiotics, opiates, etc.) may increase these side effects when used concomitantly with Vinblastine.
4. Drugs that increase hepatotoxicity: Some drugs, such as alcohol or other hepatotoxic drugs, may increase hepatotoxicity when used concomitantly with Vinblastine.
5. Drugsaffecting liver enzymes: Drugs that can alter the activity of liver enzymes (e.g., cytochrome P450 inhibitors or inducers) may alter the metabolism and levels of Vinblastine in the body.
6. Drugs that increase neuropathy: Some drugs, such as isoniazid or dapsone, may increase the risk of neuropathy when used concomitantly with Vinblastine.

Storage conditions

Storage conditions for vinblastine may vary depending on its form and manufacturer. However, general recommendations for storage of vinblastine include the following:

1. Storage in a cool and dry place: It is important to store vinblastine at a controlled temperature, usually between 2°C and 8°C. This may mean storage in the refrigerator, but not freezing. Some forms of vinblastine may require a special temperature regime, so it is important to follow the instructions on the label or information provided by the manufacturer.
2. Protection from light: Vinblastine should be stored in its original package or container to protect it from direct light, which can destroy the active ingredients of the drug.
3. Observing the expiration date: Before storage, it is important to make sure that vinblastine has not expired. Once the package has been opened, the drug may have a limited shelf life, which must also be observed.
4. Original packaging: If possible, store vinblastine in its original packaging or container to avoid contact with moisture and other substances that may adversely affect its stability.
5. Children and pets: Keep vinblastine out of the reach of children and animals to prevent accidental use.