This excerpt taken from the ENZN 10-K filed Mar 2, 2007.
There are several technologies that compete with our SCA protein technology, including chimeric antibodies, humanized antibodies, human monoclonal antibodies, recombinant antibody Fab fragments, low molecular weight peptides and mimetics. These competing technologies can be categorized into two areas:
We believe that the smaller size of our SCA proteins should permit better penetration into the tumor, result in rapid clearance from the blood, and be suitable for fusion proteins, such as immunotoxins. A number of organizations have active programs in SCA proteins. We believe that our patent position on SCA proteins will likely require companies that have not licensed our SCA protein patents to obtain licenses under our patents in order to commercialize their products. We cannot be sure, however, that other companies will not develop competing SCAs or other technologies that are not blocked by our SCA patents.