The identification of the “holes” in the available pool of licensed medicines is a key point to better target R&D activities that might lead to the discovery of new treatments. Scientists at the Institute of Cancer Research, London, have published on Nature Reviews Drug Discovery a map of all 1,578 medicinal products licensed through the Food and Drug Administration and their mechanisms of action. According to the authors, the study represents the most comprehensive analysis of existing drugs across all diseases ever conducted.
The analysis of molecular targets reveals that just approx. 3.5% of the 20,000 human proteins (667 separate proteins) are the targets of already developed medicinal products. Four are the key families of proteins accounting for 43% of all drug targets, representing the site of action of as many as 70% of all approved small-molecular drugs  created so far. Researchers identified also 189 drug targets in organisms that are harmful to humans, such as bacteria, viruses and parasites. Two drugs for every target is the average value found in humans, but some proteins – such as the glucocorticoid receptor, which is the target of 61 anti-inflammatory medicines – represent the target of several different molecules. Cancer is the area of research with the higher introduction of ‘first-in-class’ innovation, with medicines characterised by new and unique mechanism of action.
There might be a huge amount of discovery space – in the form of human genes and their related proteins – free to find innovative solutions to many diseases, suggests the paper. The map, add the authors, could also be used to identify where a treatment for one disease could be effective against another.”We need to do more to innovate in drug discovery if we are really going to tackle the major medical challenges we face, such as cancer’s ability to evolve drug resistance in response to treatment – said professor Paul Workman, chief executive of The Institute of Cancer Research -. But to help direct future efforts in drug discovery, we first need a very accurate and comprehensive picture of the targets of the medicines that have been created so far, what is currently working, and most importantly where there is the greatest potential for the future. This new map of drugs, created through the latest computational analytical technologies, will enhance our ability to use rational, data-driven approaches to identify the most promising future targets and treatment combinations for the next generation of cancer and other diseases.”
The data used to run the analysis have been extracted from various big datasets including the canSAR database at The Institute of Cancer Research (ICR), the ChEMBL database from the European Bioinformatics Institute (EMBL-EBI) in Cambridge and the University of New Mexico’s DrugCentral database. The analysis was run using Big Data Analysis techniques.