Bleomycin has been available as a cancer treatment drug since 1962. It is derived from a bacteria called Streptomyces verticillus that occurs as a fungus in soil. This derivative functions as a kind of antibiotic in the treatment of cancerous cells and tumor development. Bleomycin halts the rapid cell division that occurs in the abnormal cells of cancer. While the actual mechanism of action is not completely understood, it is generally thought that bleomycin inhibits DNA reproduction at the cellular level with some impact on RNA replication as well.
It is marketed under the brand name Blenoxane, but is available as a generic medication. Bleomycin is part of a combination of drugs used during a chemotherapy regimen and is delivered to the patient in the form of an injection or intravenously as an IV. It is not available in pill or tablet form. It is used to treat melanomas and cancers of the head, neck and upper body. It can also be useful in the treatment of testicular cancer and other genital cancers. It can also be used to treat the malignant buildup of fluid between the chest wall and the lung called pleural effusion.
Because of its longevity and the fact that it is generally one of the better tolerated medications in the arsenal of chemotherapy drugs, bleomycin is on the list of Essential Medicines put out by the World Health Organization. It continues to be included in the standard practice of care for cancer treatment around the world.
Bleomycin is generally tolerated well by patients, but does have possible side effects. Some are more serious than others. The less significant side effects occur in roughly 30% of the patients that are given bleomycin. They include:
Less often, more dangerous side effects can occur. These occur in less than 10% of patients. Patients should contact their doctor or medical caregiver if they experience any of the following:
The following side effects are severe and would indicate immediate discontinuation of use of bleomycin, as well as emergency medical treatment:
Since bleomycin came to market in the early 1960s, these most severe reactions have occurred in less than 1% of all people taking the medication, so while they are very serious, they are also extremely rare. Bleomycin can cause serious toxicity in the lungs including pulmonary fibrosis, pneumonitis and scarring of the lungs. This is more likely to affect patients who already have compromised lung conditions, elderly patients or those patients who have taken bleomycin for a long period of time, or in large doses.
Dosing is dependent of the form of cancer being treated and whether the patient is an adult or child.
For adults with squamous cell carcinoma, the recommended dosage is 0.25 units/kg to 0.50 units/kg delivered twice weekly. Pediatric patients typically receive the same dosage.
The same dosage is recommended for treatment of testicular cancer in both adults and pediatric patients. This is also true for treatment of ovarian cancer and cancer of the vulva.
For the treatment of Hodgkins disease in adults, recommended dosage is 0.25 units/kg to 0.50 units/kg once or twice weekly. Because there have been documented cases of anaphylaxis in lymphoma patients (very rare), it is recommended that the patient be held for observation for several hours following the administration of the first dose. The same protocol is recommended for children.
When used to treat non-Hodgkins lymphoma, the same dosage levels and observation protocols should be followed. In most treatment using bleomycin, improvement in the patient should occur after the first two to three weeks. If improvement does not happen during this window, it is not likely that treatment using bleomycin will prove effective for the patient.
For treatment of malignant pleural effusion in both adults and children, the standard treatment is a single injection of 60 units of bleomycin. This injection is administered through a tube into the chest cavity through an incision into the chest wall.
In situations where the patient is also suffering renal impairment, dosage levels of bleomycin should be adjusted to 40%-70% of the usual recommended dosage.
Bleomycin is known to interact with 186 medications. Many of those interactions are mild and do not impact a patient's chemotherapy treatment plan. However, there are over 30 drugs that interact very negatively with bleomycin, and the two medications should not be taken concomitantly. These include:
Bleomycin is not recommended for women who are pregnant. It represents serious risk to the fetus, and both men and women using this drug should avoid conceiving a child. Women should avoid breastfeeding while being treated with bleomycin. Patients undergoing chemotherapy treatment that includes bleomycin should avoid taking aspirin or any product containing aspirin. Patients should inform their doctors and care providers about any medications, including homeopathic drugs, over the counter medications and supplements to avoid negative interactions. Patients should avoid any sort of immunization or vaccination during their chemotherapy.
If the patient has kidney or liver disease, or has had that condition in the past, it is important to share that with the doctor.
While the patient is undergoing treatment, it is critical that their blood and lung functions are checked regularly. Rarely, bleomycin can cause serious pulmonary issues, so chest x-rays are recommended as well to check for pulmonary issues such as pneumonitis and other irregularities.
Bleomycin may also cause damage to the renal system, so kidney function should be monitored regularly during treatment. Liver function should also be monitored.
Because loss of appetite and nausea are very common side effects of bleomycin, anti-nausea medicine may be necessary to help the patient maintain a healthy weight. Weight should also be checked often, as well as dehydration risks.
Patients need to maintain a healthy diet and get plenty of rest to counteract the effects of fatigue. They should also avoid alcohol use.
In situations where the patient is undergoing chemotherapy with bleomycin and surgery is indicated, doctors need to administer oxygen very carefully during the surgical procedure as the oxygen can increase the toxicity in the lungs.
A condition called infectious pneumonitis may develop, particularly in older patients. Because of this risk, a patient should not be given more than 400 units of bleomycin over the course of their lifetime.
It is possible for patients to be allergic to the substances that make up bleomycin, and would be contraindicated in those cases.
Because bleomycin is delivered to the patient in the form of an injection or through intravenous fluid drip, patients do not need to worry about storing the medication in their home. Medical facilities, including hospitals and cancer treatment centers, that deliver chemotherapy regimens should store the vials of bleomycin powder in a refrigerated area between 2 and 8 degrees Celsius (35-46 degrees Fahrenheit). Once the powder has been reconstituted into liquid form, either as an injection or as an IV drip, it should be administered to the patient within 24 hours of reconstitution. Bleomycin vials come in 15 unit doses and 30 unit doses.
Bleomycin has been available for the treatment of many kinds of cancer for over 50 years. It is a vital and important tool in fighting squamous cell carcinoma cancers, as well as lymphomas, genital cancers and malignant pleural effusion. It has also shown some efficacy in the treatment of Kaposi's Sarcoma, a form of cancer associated with HIV/AIDS. It is used in chemotherapy protocols for treatment of these cancers, and is delivered through IV, subcutaneous or intramuscular injection. It is not available as a tablet or pill. Bleomycin is derived from a soil based fungus called Streptomyces verticillus, and functions as an antibiotic in the body. Its primary mechanism is as a DNA inhibitor, which slows the growth of cancerous cells by interrupting their replication. It also impacts the replication of RNA. It is hypothesized that the chemical function of the interruption occurs when bleomycin prevents the enzyme thymidine from incorporating into the DNA strands of the abnormal cancer cells. Through this interruption, bleomycin in combination with other medications such as doxorubicin, destroys cancer cells and shrinks cancerous tumors. The levels of toxicity created by bleomycin in the human body prevent its use in other antibiotic applications.
Bleomycin represents one of the foundational medications in the treatment of a family of cancers that affect the head and neck, as well as some genital cancers. It has been on the market for a long time, and while it does have many side effects and does carry with it some serious risks, it is better tolerated by most patients than other medications that have a similar mechanism of action. It is typically given once or twice a week for a period of three weeks at a time. If the tumor does not respond or the patient does not show improvement in the first few weeks of treatment, it is unlikely that this particular chemotherapy regimen will prove effective. There is a lifetime limit for patients with regard to bleomycin. Generally, 400 units is the maximum amount of the drug that anyone can take without showing real signs of toxicity, often in the kidneys, liver or bloodstream. The administration of bleomycin should be monitored very closely by the team of health care professionals taking care of the individual patient, for both short-term effects and risks as well as the risks posed to the patient over a lifetime.