Drug target validation has become the critical step in maintaining profitability for the pharmaceutical industry, claims a new report from market research company Business Communications. Drug developers must accelerate identification and validation of potential new products - to facilitate this, suggests the report, genomics technologies could allow companies to minimise product failures in trials and move candidates through the development process more rapidly.
According to the report, the worldwide market for genomics technologies used in the processes of drug target screening, drug target identification and drug target validation is a rapidly growing one. Comprised of bioinformatics, comparative/functional genomics, high-throughput screening and proteomics - the market was estimated to be $7 billion in 2002, and is expected to grow at an AAGR (average annual growth rate) of 14.1 per cent to reach $13.6 billion by 2007.
The greatest growth will occur in the nascent market of protein microarrays (a part of the proteomics market), with a staggering AAGR of nearly 48 per cent, but all sectors of this area will exceed 10 per cent AAGRs throughout the forecast period. Proteomics will see growth from $1.9 billion in 2002 to $4 billion in 2007, continues the report.
The success of various genome-sequencing projects has resulted in a need for new tools to effectively study the vast amounts of complex genetic data being produced. In general, the post-sequencing era is marked by a shift away from studies involving the piecemeal analysis of individual genes to global, genome-wide strategies.
Understanding the function of the estimated 40,000 human genes and the hundreds of thousands of proteins they encode is the greatest challenge of the post-sequencing era.
The 30,000 to 40,000 human genes suggested by genome sequencing data create many more gene products (proteins) than a simple one-to-one expression process would suggest because of variations in splicing of ribonucleic acid (RNA) transcripts, differences generated by posttranslational modifications and other factors. The size of the transcriptome-the set of all cellular messenger RNA transcripts-is an enormous unknown. One gene does not by any means equal one protein.
Because so many proteins are produced and because not all of them are "druggable"-capable of being used as selective drug targets-it is important, writes the report, to establish, early on, the validity of each target. This is the process of target validation. If a target is not properly validated, there can be real problems. For example, PTEN is a lipid phosphatase that is a negative regulator of insulin signaling and therefore it would seem a reasonable candidate to consider for the control of diabetes. However, a study of the functional genomics of PTEN revealed that it is also a tumour suppressor related to p53 and it can therefore also act as an oncogene.
Prior to the sequencing of the human genome, a primary obstacle in the drug discovery process was the identification of a potentially therapeutic drug target. In 2003, drug companies have more drug targets than they can possibly manage or assess. It is estimated there are as many as 10,000 putative drug-target genes in the human genome. According to BCC, the primary obstacle to drug development has shifted from drug target discovery to drug target validation.
The key step in the identification of drug targets is to identify the genes of the human genome and determine their functions. Genomics companies are developing a plethora of approaches and tools to facilitate this process. Whole genome approaches will improve the drug development process as well as affecting the diagnosis and real-time monitoring of disease.
The validation of drug targets is the crucial rate-limiting step in drug discovery and development in the genomics era. Some of the most lucrative deals signed between genomics companies and pharmaceutical firms involve the discovery and delivery of validated drug targets, concludes the report.