Effectiveness of Drug Screening System Utilizing Active Learning

NEC Corporation has announced that it has verified the effectiveness of a drug screening system, ChemMiner™, which utilizes data mining techniques such as active learning, enabling a ten-fold improvement in screening performance, resulting in an approximate 90% decrease in screening cost, as compared with conventional screening systems.

The system's effectiveness has been verified through collaborative research with Tanabe Seiyaku Co., Ltd, a Japanese pharmaceutical company, to which the system will be delivered in September.

The main points of this system are - development of a technique called "exponential selection." At an actual screening site, detection of active compounds (compounds that are effective for drug purposes when they interact with protein in some form) is rare, thus discovery of active compounds has been one of the issues with conventional screening methods such as random screening to date.

NEC's technique is designed to allow scoring of compounds by the information gained from prior screening by low or high probability.

This method aims to detect low scored compounds with low probability to aid selection of more informative compounds during the next stage of experiments/screening.

This method is designed to enable the finding of extremely rare active compounds from anywhere from several hundred thousand to several million sets of compounds.

The second step is - Development of a technique called "descriptor sampling." With active learning, data learned at an early stage can limit the diversity of a system, thus new types of compounds are often not discovered, representing another major issue of the random screening method.

With this technique, some descriptors are masked and are not utilized for learning, allowing greater diversity, which can lead to the finding of diverse groups of compounds.

The third step is - Improved system performance as compared with conventional methods: By applying first two methods to a type of G protein-coupled receptor, NEC was able to demonstrate improved screening system performance as compared with conventional methods for several data groups.

The number of assay wet experiments, which are vital to the finding of active compounds, carried out during screening was reduced by anywhere from 88% - 97% compared to conventional methods.

According to NEC, this improvement achieves a substantial reduction in screening costs by approximately 90% from several hundred thousand to several tens of thousands of dollars.

During the drug discovery process, systems will screen a huge chemical library, consisting of anywhere from one hundred thousand to one million chemical compounds, in order to search for chemical compounds effective in drug creation.

This incurs exorbitant cost as screenings require the performing of costly wet experiments. NEC expects this system to respond to the need for an economical drug screening system, which has been long sought after in the pharmaceutical field.

NEC's Bio-IT Business Promotion Center will begin offering outsourcing services for the screening of drugs from September, 2005 and plans to begin sales of ChemMiner™ at a later date.