From the first days of its foundation in 1999, ZL followed a somewhat unique business model at the time. The major feature of this model is that first ZL's scientists test the original idea in relevant cell cultures, followed by contracted scientists carrying out most of the remaining R & D work. When the in vivo data show promise of clinical use, and market analysis indicates the need for such application, this is when ZL decides to file one or more patent application(s). In order to move the best projects forward, acute and chronic toxicology studies are performed followed by in vitro and in vivo "mechanism" studies as well as analysis of drug distribution and metabolism. A major fund raising effort precedes a move from this point toward drug production and the first-in-man clinical trials. ZL is in the process of completing steps 4 and 5.