Virtual Screening: An Emergent, Key Methodology for Drug Development in an Emergent Continent. A Bridge Towards Patentability.

Introduction

The advances in Organic Chemistry and in technologies related to chemical synthesis have resulted in a tremendous increase in the rate of development of new chemical entities. The number of known chemical compounds has been growing exponentially during the last four decades. In 2009, the Chemical Abstract Service (http://www.kubinyi.de/). Exploring this vast chemical space in an exhaustive manner (through systematic pharmacological screening of all known chemical entities against all possible biological targets) is no longer feasible (nor rational) in terms of time and resources that ought to be invested. Instead, Medicinal Chemists have developed alternative approaches to explore the haystack in a cost and time-efficient manner. High Throughput Screening (HTS), for example, merges microarrays and robotics to test small samples of a series of compounds against a wide range of in vitro tests (Pereira & Williams, 2007). Instead of asking a researcher to carefully analyze each element of the haystack until the unique properties of the needle are revealed to the experienced eye, HTS replaces (to some extent) the human ingredient by automated technologies relying on robotics, controlling software and sensitive detectors. On the other hand there is Virtual Screening (VS): a heterogenic set of computational techniques to explore digital representations of chemical entities recorded in chemical databases, in order to indentify potential candidates gathering an array of structural constrains or requisites that are somehow linked to certain biological and/or chemical properties. The use of VS has been progressively increasing since the first campaigns in the early 1990s, as illustrated in Figure 1.

Figure 1.

Frequency of appearance of the expression “virtual screening” in article titles or keywords (considering both original articles and reviews) in well-know scientific literature browsers Scirus (public access, http://www.scirus.com) and Scopus (access under subscription). The expansion in the use of VS techniques can be clearly observed.

In this chapter we will analyze the advantages and types of VS and we will discuss the opportunities linked to the use of this approach in Latin America, related to potential patenting of research and development (R&D) on new drugs and possible collaborations between the academic and the industrial sectors. We will also include a short section on perspectives of VS.