A minimalistic explanation....
Peregrine has exclusive rights to Bavituximab, a first in class compound with the ability to single out cells which have a chemical known as PS exposed on the exterior of cells. PS becomes exposed on dying cells as well as cancer cells and cells infected with a virus. It basically can tell the 'wolf in sheeps clothing" in the body. The reason the bodies immune system does not attack most viruses and cancers is that it thinks they are normal cells.
The trend has been up for six months and on Thursday, May 29th 2009 the stock saw an unprecedented one day volume burst of over 36 million shares.
http://finance.yahoo.com/q/ta?s=PPHM&t=1y&l=on&z=m&q=l&p=m50&a=&c=
The risk / reward is woth a look.
Please read up on Peregrine Pharmaceuticals (Nasdaq:PPHM) for more information.
http://www.peregrineinc.com/
Best of Luck!