The drug Vinblastine belongs to the group of chemotherapeutic agents. It is used to treat cancer.
What is Vinblastine?
Vinblastine is also under the names in medicine Vinblastine sulfate or Vincaleukoblastin known. The chemotherapeutic agent is the most famous representative of the vinca alkaloids. Vinblastine is an alkaloid of the pink catharanth. This plant is also called pink room evergreen or Madagascar evergreen and belongs to the genus of catharanth.
The vinca alkaloids have the ability to bind to the protein tubulin, which means that they inhibit the formation of microtubules, which are bundles of threads.
In this way, the cancer cells, which divide rapidly, are also affected. Vinblastine exists as a yellow powder at room temperature. The aromatic hydrocarbon molecule can be easily dissolved in water. Vinblastine has been approved in Europe since the early 1960s. In Germany, the drug is sold under the trade name Velbe®.
Pharmacological effect
Vinblastine belongs to the cytostatics and is one of the cancer-inhibiting drugs. In addition, it forms a mitosis inhibitor because it counteracts mitosis (the division of cells). It is found in medicines as vinblastine sulfate. The active ingredient is obtained from the rose-colored Catharanthe.
During the process of cell division, bundles of threads (microtubules) are built up. These attract the duplicated genome chromosomes and thus ensure the creation of an independent cell. Vinblastine has similar effects as the gout preparation colchicine and works directly on the structure of the thread bundles. For this purpose it is bound to the building material tubulin, which interrupts the process of thread production. In addition, existing microtubules are dissolved by the vinblastine. The network that normally arises to allow the double genetic material to be properly split up during cell division also suffers. Vinblastine is also said to have a killing effect on cells that temporarily do not multiply.
A disadvantage of the chemotherapy drug, however, is that it also affects the healthy cells, which in turn manifests itself in unpleasant side effects. However, due to their ability to divide rapidly, the cancer cells are more affected than the healthy cells. The half-life of vinblastine is considered to be long and is up to 24 hours.
Medical application & use
In some cases, vinblastine is given as a single preparation. As a rule, however, it is used in conjunction with other cytostatics or radiation treatments as part of cancer treatments.
The most important indications for the vinca alkaloid include malignant tumors of the lymphatic system such as Hodgkin's disease, special tumors of the lymph glands such as non-Hodgkin's lymphoma, recurrent breast cancer with metastases (daughter tumors) and advanced testicular cancer.
Another area of application is Langerhans cell histiocytosis. This is a special form of bone marrow cancer. Other areas of application are Kaposi's sarcoma, hairy cell leukemia and chorionic carcinoma (villus cancer) when other cytostatic drugs have no effect.
Vinblastine is administered as an intravenous injection. Treatment usually takes place once a week. If the patient's liver is not working properly, a lower dose must be administered. Do not inject into the spinal canal. There is a risk of the meninges sticking together.
Risks & side effects
Treatment with vinblastine can cause undesirable side effects. The vinca alkaloid causes damage to the white blood cells (leukocytes), while the red blood cells (erythrocytes) are less affected. However, since the bone marrow recovers quickly, the lack of leukocytes rarely results in febrile infections.
Common side effects of the cytostatics are nausea, vomiting, the formation of blisters on the skin and in the mouth, a lack of blood platelets, constipation, intestinal obstruction, abnormal sensations of the nerves, bone marrow dysfunction, anemia (anemia), bleeding from the rectum, a bloody one Inflammation of the intestine and refusal to eat. In addition, patients often suffer from hair loss. However, this is not done completely. In some patients, the hair grows back even during the vinblastine therapy.
In some cases, inflammation of the throat, pain in the tumor area, a general feeling of illness, cramps, headache, inflammation of the nerves, numbness, tinnitus, dizziness, cardiac arrhythmias, angina pectoris attacks or depression may occur. In addition, even with the correct dosage, there is a risk that the patient's water balance will derail.
If the patient suffers from hypersensitivity to vinblastine or other vinca alkaloids, therapy with the cytostatic must be avoided. This also applies to infections that are difficult to control and a lack of white blood cells that is not caused by the cancer.
A thorough benefit-risk assessment by the doctor is necessary in the case of circulatory disorders in the coronary arteries, liver dysfunction, an infestation of the bone marrow with cancer cells and in elderly patients, in whom a drop in blood pressure can intensify.
During pregnancy, vinblastine should only be administered on express medical advice. Animal experiments led to changes in the genetic make-up. Therefore, there is a risk of deformities in the unborn child. The use of safe contraceptive methods is recommended for women and men of childbearing potential during vinblastine therapy. In addition, there is a risk of permanent infertility due to the cytostatic drug.
If vinblastine is given with other cancer-killing drugs, the side effects can increase. If vinblastine is taken at the same time as the antifungal drug itraconazole, there is a risk of intestinal paralysis or nerve damage. In addition, permanent lung damage is possible due to the simultaneous use of vinblastine and the anti-cancer drug mitomycin C.
