Avastin in Breast Cancer

[jimbo]

Bevacizumab (trade name Avastin, Genentech/Roche) is a humanized monoclonal antibody that recognizes and blocks vascular endothelial growth factor A (VEGF-A). VEGF-A is a chemical signal that stimulates the growth of new blood vessels (angiogenesis).

Blood vessels grow uncontrollably in cancer, retinal proliferation of diabetes in the eye, and other diseases. Bevacizumab can block VEGF-A from creating new blood vessels. Bevacizumab was the first clinically available angiogenesis inhibitor in the United States.

FDA Questions Avastin's Use in Breast Cancer

“The risk-benefit ratio of [Avastin] when added to the standard chemotherapeutic regimens...may not be considered favorable, the agency said.”

Non-receptor tyrosine kinases (EC 2.7.10.2)

ABL family	ABL1 · ARG
ACK family	ACK1 · TNK1
CSK family	CSK · MATK
FAK family	FAK · PYK2
FES family	FES · FER
FRK family	FRK · BRK · SRMS
JAK family	JAK1 · JAK2 · JAK3 · TYK2
SRC-A family	SRC · FGR · FYN · YES1
SRC-B family	BLK · HCK · LCK · LYN
TEC family	TEC · BMX · BTK · ITK · TXK
SYK family	SYK · ZAP70

Jimbo's Opinion:

FDA is doing its best to have cancer drugs available to the desperate patients despite the questionable benefit. It's a difficult job, but it might make more sense if FDA demands more scientific design as well as analysis of the drug trials to the drug companies. We do have means available to see which patients may get benefit from Avastin in breast cancer, either adjutant or metastatic settings. For example, we don't try Herceptin for HER2 negative patients. It's about time to end the shotgun approach in drug trials and start a more targeted aim at the selection of patients with advanced technologies, at least IHC to select patients who have at least reasonable chance of getting benefit.