Virtual screening - what does it give us?

In current pharmaceutical research, lead compounds of high quality and structural diversity are key to the successful optimization of development candidates. In-house compound libraries at pharmaceutical companies, tested using HTS assays, are the major source of leads for new projects. However, these physically existing compounds, stored in microtiter plates in dispensaries, represent only a tiny fraction of the drug-like chemical space. Virtual screening offers many possibilities for new structures beyond those found in in-house libraries. During the last decade, a huge number of different virtual screening methods have been reported and used to search for novel bioactive compounds for many targets. This review addresses the current status of virtual screening, highlighting achievements as well as challenges, along with the value of virtual screening, and recent examples of successful applications.