On May 19, 2002, researchers from the National Cancer Institute reported that the molecularly targeted drug bevacizumab slowed tumor growth in patients with metastatic renal cell carcinoma, the most common form of kidney cancer in adults.

Tumor growth slowed considerably in trial patients who were given a high dose of bevacizumab. The time it took for the cancer to show measurable growth was two and a half times longer in these patients compared to those who did not receive the drug (approximately five vs. two months).  Although the difference was small, it was highly statistically significant. There was also a smaller, but still significant, effect from the lower dose of bevacizumab.

Kidney cancer is diagnosed in more than 30,000 people each year in the United States. In this phase II trial, 116 patients with advanced cancer and no known effective treatment options were randomly selected to receive placebo (no drug), a low dose of the drug (3 mg/kg), or a high dose (10 mg/kg). Because only minimal side effects were associated with the drug, researchers were able to design a double-blind trial, in which neither patients nor physicians knew which treatment was being given. This rigorous trial design greatly reduces biased results.

More than 20 additional clinical trials are currently underway to evaluate bevacizumab as a treatment for various types of cancer. The drug is being tested in phase III trials for breast and colorectal cancer. Phase II trials with bevacizumab include those for prostate, breast, colorectal, cervical, ovarian, pancreatic, and lung cancers, as well as for mesothelioma and several types of leukemia.