Key Terms: Carcinoma in situ, Instillation, Intravesical.
Definition
Valrubicin (also known as Valstar) is a chemotherapeutic drug that interferes with the metabolism of DNA, thus disrupting the proliferation of cells, including cancer cells.
Purpose
Valrubicin is an antineoplastic drug that is used as a treatment for a form of bladder cancer called papillary bladder cancer when the bladder cannot be surgically removed due to increased risk of morbidity or mortality. It is also being tested as treatment for several other types of carcinoma in situ.
Description
The Food and Drug Administration approved valrubicin for bladder cancer treatment in 1998. As of 2000, it was being tested in clinical trials for both bladder and ovarian cancer treatments. It is an anthracycline-like compound that acts by penetrating cells and disrupting the dividing cell cycle by interfering with DNA metabolism. Valrubicin acts by inhibiting nucleoside incorporation into nucleic acids, thus, causing major damage to DNA. Research performed in 1999 indicated that valrubicin entered cells faster than doxorubicin, another anthracycline. Research has also shown that complete response is seen in one in five patients.
Recommended Dosage
Valrubicin is only available in instillation form and can only be administered under the supervision of a physician. During initial clinical trials patients received doses ranging from 200 milligrams to 900 milligrams each week. The normal dose is 800 milligrams once a week for six weeks. However, dosing may vary from patient to patient. The drug is administered intravesically (directly into the bladder) through a catheter tube that penetrates into the bladder wall. Once delivered to the bladder the solution should be maintained in the bladder for approximately two hours.
During clinical trials for ovarian cancer, valrubicin is administered through the abdomen.
Precautions
There are other bladder problems that may affect the use of valrubicin. Patients with bladder irritation can have an increased risk of unwanted effects. Patients with perforated bladders should not take this medication. Patients with small bladders could have trouble holding all of the medication. Finally, if patients have urinary tract infections, they should use caution when taking this medication.
Valrubicin has not been studied in pregnant women, but it has been studied in pregnant animals. In animals it can cause birth defects. Therefore, women who are pregnant or breast-feeding should not take valrubicin. Additionally, women should not become pregnant while on this medication. Men taking this medication should not engage in procreative activities. Both men and women should use appropriate forms for contraception to avoid causing pregnancy.
There have not been appropriate studies done specifically on children or the elderly to determine the risk of using this medication in these populations. However, this drug is not expected to act differently in the elderly than it does in younger adults.
Side Effects
During the six-week course of treatment patients could experience one or more side effects. The most common are loss of bladder control, increased frequency of urination, and blood in the urine. Other less common and rare side effects are bladder pain, pelvic pain, urethral pain, and loss of the sense of taste.
Interactions
As of 2000 there were no known drug-drug interactions with valrubicin.
