Jan. 28, 2004 -- A first-of-its-kind cancer drug, Avastin, starves tumors and may help patients in both foreseen and unforeseen ways in the near future, experts say.
First identified in 1989, Avastin is set to be considered for FDA approval for colon cancer this spring and may soon be added to existing cancer treatments and potentially be used to nip cancers in the bud. Experts spoke on Avastin and other similar drugs Tuesday at a meeting at the New York Academy of Sciences in New York City.
'Unprecedented New Approaches'
The new drug is part of a class of cancer drugs known as angiogenesis inhibitors, which work by shutting down the blood vessels that feed tumors, effectively starving the tumor. Avastin targets a protein called vascular endothelial growth factor (VEGF), which plays a role in making new blood vessels for tumors (a process called angiogenesis).
The new drug, which is given by injection, is being tested against colon cancer, kidney cancer, prostate cancer, non-Hodgkins lymphoma, and many others. Avastin is manufactured by Genentech, a WebMD sponsor.
"In the near future, angiogenesis inhibitors including Avastin may be employed in unprecedented new approaches that are not feasible with conventional therapy," forecasts angiogenesis pioneer Judah Folkman, MD, the Julia Dyckman Andrus Professor of Pediatric Surgery at Harvard Medical School, where he is also professor of cell biology.
In a recent study of people with widespread colon cancer, people who received Avastin along with standard chemotherapy lived a little more than four months longer than people who received only chemotherapy. These results were presented at the annual meeting of the American Society of Clinical Oncology in Chicago in June.
While four months may not seem like a lot, experts note that just 10 years ago there was no available treatment for advanced colon cancer.
"Clearly Avastin can be added to chemotherapy," Folkman says.
And the rest we can't predict, he says, likening the new drug and others in its class to the Wright brothers' first flight of 150 feet in 1903. No one could have imagined that in 1927 Charles Lindbergh would fly 3,500 miles over the Atlantic Ocean -- alone, Folkman says.
Angiogenesis inhibitors also seem to have few, if any, side effects. Other angiogenesis inhibitors, such as Endostatin, are also showing promise for the treatment of various forms of cancer, with no side effects.
Napoleone Ferrara of Genentech says the only certain side effect of Avastin may be mild high blood pressure but this can be easily controlled with medication.
"Hopefully these drugs reduce harsh side effects of cancer therapy," Folkman tells WebMD.
Cancer as a Manageable Condition?
Many tumors are microscopic and don't develop blood vessels, Folkman says. In fact, such cancers are actually in place in all organs -- even in young people. Cancers become a problem when they develop a blood supply -- become angiogenic.
Currently, Avastin is given to cancer patients in clinical trials only after the angiogenic switch has been activated, after they have failed other treatments, Folkman says.
If you have a drug with very few side effects, you could feasibly use it before cancer becomes visible if there were a good marker, he explains.
If this proves true, Folkman suggests that "maybe we can even convert cancer into a chronic manageable disease like diabetes and heart disease."
Marla Weetall PhD, of PTC therapeutics, a biotech firm in South Plainfield, N.J., and co-chair of the biochemical pharmacology discussion group at the New York Academy of Sciences, adds that "it's becoming clear that anti-angiogenesis will be a fourth arm in the treatment of cancer along with radiation, chemotherapy, and surgery."