Avastin: A Bad Idea

Avastin used to be FDA approved for treatment of breast cancer, but no more.Why? Why approve it and then not? What is this Avastin and what does it do? Could we have anticipated the problems and side effects?

Avastin (bevacizumab) is an antibody that binds to vascular endothelial growth factor-A (VEGF), a “word” in the “language” that cells use to communicate with each other. Since one meaning of this “word” is “grow blood vessels,” Avastin inhibits the formation of new blood vessels that supply tumors with their source of oxygen and nutrients. Seems like a great idea. But is it?

The problem is that VEGF is just one word in the entire cellular language. And, just as “pretty” means something very different from “pretty ugly,” so VEGF does different things in different contexts. Besides the above function, VEGF also “speaks” to the immune system, “tells” platelets to form plugs, inhibits cellular suicide, plays a role in bleeding, and more. Taking this word out of the body’s language is bound to have profound, and possibly devastating, effects.

Avastin has been regularly prescribed for use in patients with metastatic breast cancer, having been approved by the FDA in 2008 via their accelerated approval process. It isstill used in treatment of lung, kidney, brain and colon cancer (approved 2004). But, on November 18, 2011, the FDA released a statement saying that Avastin is neither safe nor effective in delaying cancer growth and improving quality of life. Not surprisingly, Genentech, the sponsor of the clinical trials and the manufacturers of the drug, did not agree with the FDA’s actions.

Frankly, a quick perusal of Genentech’s patient information website makes one wonder why Avastin was ever approved for treatment of anything. The side effects include heart attack or stroke in 2.4% of patients, high blood pressure in up to 18% of people, serious bleeding, gastrointestinal perforation, slow wound healingand more. And, in Genetech’s own words, “no data have shown whether or not Avastin improves disease-related symptoms or survival in people previously treated for [brain cancer].” In patients with lung, kidney or colon cancer, Avastin is prescribed alongside other drugs, making it a little challenging to determine how helpful Avastin itself is. To sum up, it looks like Avastin probably won’t help, but it definitely will hurt.

So, why was Avastin approved for use in breast cancer in the first place? Apparently, an advisory panel voted 5-4 that it not be. Well, the FDA wants to bring cancer drugs to the market as soon as possible, it sounded like a good idea, and so they approved it. Fortunately, the FDA also required two additional clinical trials, the results of which did “not justify the continued approval of the drug,” thus approval has been withdrawn.

So, they made a mistake. A costly, even deadly, mistake for many. But, it is important to be aware that the FDA decision-making individuals are no more capable of predicting the future than the rest of us. Moreover, they were and still are under tremendous pressure. There is the inevitable outcry from desperate patients after hearing that this drug is being withdrawn. They had pinned their hopes on it and now feel they are being left out in the cold. In addition, the decision makers are doubtless being pressured by the people at Roche Holding AG, which stands to lose $873 millionin revenue. But, if the facts advertised on the Genentech website are accurate, the FDA made the right decision and AITSE congratulates them for practicing integrity in pharmaceutics.