Published August 1998
Combinatorial chemistry has become a powerful tool for drug discovery in the pharmaceutical industry. First used in 1982 to create libraries of peptides from different amino acids, it has evolved into a technology that is used in a widening range of applications. Combinatorial chemistry synthesizes a large number of compounds by making all possible combinations of a small number of reagents in a given reaction sequence, thereby reducing the time needed for drug discovery. The practical application of combinatorial chemistry has required the development of a number of enabling technologies, many of which have emerged from small start-up companies. These enabling technologies include automated synthesis of chemical libraries, spacially arrayed libraries, computational chemistry software, solid-phase chemical synthesis, chemical encoding, software for managing and analyzing combinatorial library data, and microfluidic techniques for miniaturized chemical synthesis. This review provides an overview of these technologies and their relationship to applications of combinatorial chemistry.
Beyond the discovery of physiologically active compounds for drugs or pest control, combinatorial chemistry's promise of decreasing the time required for discovering and developing chemical products has attracted its use in industries other than pharmaceuticals or agriculture. Catalyst discovery and optimization, luminescent materials, superconductors, semiconductors, pigments, lubricants, coating formulations, and reaction optimization are all possible applications. However, the market and financial conditions under which the products in these industries are developed differ enormously from those in pharmaceuticals.
In this review we assess the financial implications of combinatorial chemistry on the development of different kinds of products using data reported by various sources for the time and expenditure involved in bringing a product to market. We examine how the reduction in time and expenditure resulting from the application of combinatorial chemistry would affect the market size required to produce an adequate return on capital. Our calculations show that if combinatorial chemistry can reduce the time required for drug discovery from its current average of 4 years to 1 year, then the peak market size required for a new drug could be reduced by approximately 20%. Similarly, if the development time for a new chemical could be reduced from 5 years to 3 years, the maximum required market size could be reduced by 25%.