Angiogenesis Inhibitor Approved by FDA
Bevacizumab, an antibody that interferes with tumor cells' ability to make new blood vessels, was approved yesterday by the Food and Drug Administration (FDA) for the first-line treatment of metastatic colon or rectal cancer.
The product, which will be marketed by Genentech Inc. under the brand name Avastin, is described as the first angiogenesis inhibitor to reach the market. Genentech said it will start shipping the drug by Monday.
According to the product's FDA-approved labeling (PDF), bevacizumab is to be used with intravenous fluorouracil-based chemotherapy in patients who have not previously been treated for their cancer.
The recommended dosage of bevacizumab is 5 mg/kg administered as an intravenous infusion once every two weeks until the cancer progresses. Although the first dose should be administered over 90 minutes after the other drugs in the treatment regimen have been given, the second dose of bevacizumab may be delivered over 60 minutes and subsequent doses over 30 minutes. The product should not be administered for at least 28 days after major surgery and should be given only after the surgical incision has completely healed.
A boxed warning in the product's labeling states that bevacizumab is linked to three uncommon but serious events: perforation of the colon, impaired wound healing, and pulmonary or internal bleeding. The most common adverse effects reported from the company-sponsored clinical studies were hypertension, pain, upper-respiratory-tract infection, tiredness, shortness of breath, blood clots, nosebleed, diarrhea, vomiting, constipation, protein in the urine, headache, loss of appetite, mouth sores, and a scaly, red inflammation of the skin.
The product will be supplied in 4- and 16-mL single-use glass vials at a concentration of 25 mg of bevacizumab per milliliter of phosphate-buffered Water for Injection, USP. Until use, the vials must be refrigerated. When diluted with 0.9 percent sodium chloride injection to a total volume of 100 mL, the drug is stable for up to eight hours under refrigeration. The drug must not mix with dextrose-containing solutions.
Bevacizumab inhibits angiogenesis by binding to vascular endothelial growth factor and preventing it from enhancing the blood supply to a tumor.