Discovery and Development of Drugs

The development of a new drug is a long, tedious, and expensive process. It takes about 8 to 12 years from the time a new drug substance is 

The well-known drug Aspirin can demonstrate the various stages in the life of a drug substance. It was known since ancient times that the bark and leaves of the willow tree can provide relief from pain and fever. In 1832, the German chemist Piria isolated salicylic acid as the active substance in the plant material. Salicylic acid became the lead substance for further development. Soon a synthetic route was developed that replaced the tedious extraction process. Salicylic acid was used as a pain remedy, but because of its high acidity it had severe side effects when applied orally. In 1887, Felix Hoffmann, a chemist at Bayer AG, realized that the ester form of salicylic acid, acetylsalicylic acid, had fewer side effects and was even more efficacious than the free acid. The Bayer Company marketed the ester under the trade name Aspirin, which soon became the number one selling drug worldwide and is still a synonym for pain relief today. 

However, the story was not over. About 80 years after the introduction of Aspirin as a pain reliever, it was established that acetylsalicylic acid prevents heart attacks and strokes and reduces the risk of death during a suspected heart attack. In 1982, John R. Vane was awarded the Nobel Prize for medicine for discovering the basic mechanism of the action of acetylsalicylic acid. 

Only one out of 10,000 substances that enter the development pipeline pass all the tests and become new drugs in the market. Because of the 

The lead compound serves as a model for further development. Similar substances are synthesized and compared to the lead. The chemical structure is elucidated and carefully analyzed to determine which part of the molecule is responsible for the pharmacological effect. It is called the pharmacophore. The original lead compound can be modified to change its physical and physiological properties, but the pharmacophore remains the same. This principle is illustrated by the P-lactam pharmacophore in structures 1 to 4. 

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Various strategies for exploitation or limitation of the impact of transporters are available for the discovery and development of drug candidates. Most often, the impact of transporters has been realized retrospectively. However, as knowledge increases on transporter expression and function, genomics of transporter, SAR, and protein structure, the basis for a rational design of substrates or inhibitors of transporter activity is enhanced. 

To promote and disseminate novel scientific advances in the areas of discovery and development of drug substances and products through themed meetings and workshops in pharmaceutical technologies or pharmaceutics and drug delivery sections... 

Where have the increasing funds devoted to pharmaceutical R D been applied Have they been used increasingly for the advancement of scientific knowledge within companies Have they been increasingly targeted to discovery and development of drugs that treat diseases through... 

Advances in identification of therapeutic targets and medicinal chemistry to interact with these targets have driven changes in the way that toxicologists contribute to the discovery and development of drugs. The emphasis is... 

The dates of these isolations and others of the primary steroid hormone group are recorded in Table III. This overall timetable of events also shows other key stages in the discovery and development of drugs from natural sources. Most of these stages normally occur but not always in the order listed. 

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