Nearly all pharmaceutical firms are on the look-out for new medicinal compounds which would be safe and effective medicines that could possibly:
1. Help prevent disease (preventive medicine)
2. Slow down the progression of a disease
3. Alleviate symptoms
4. Cure disabling or lethal conditions.
Using techniques such as quantitative structure-activity relationship (QSAR), a list of probable medical compounds is prepared. From this list of probable medicines, the target compound is narrowed down upon by the process of elimination.
Various factors play a role in influencing the discovery and development of new medicines.
1. Government policies that favor the development of new life saving drugs.
2. Increase in scientific understanding of human biology and anatomy such as new discoveries in stem cell research, gene therapy, new vaccines that may enable scientists to understand how a disease is caused and what could be the processes in the body leading to it.
3. Aggressive funding for research.
4. Global effort for the elimination of specific condition such as malaria, dengue, etc.
5. Search for a cheaper alternative to existing medicines that are available in the market.
6. Chance discovery of other uses of the drug. For example, Minoxidil was originally used to treat high blood pressure but was later found to increase hair growth as well.
Discovery of a new chemical entity
Scientists begin by targeting a known step in the progression of a disease or working out the functional causes of a disease. They then determine the step which can be altered or interrupted to prevent the disease from expressing itself.
The new promising drug may inhibit the production of specific chemicals, interfere with the way certain cells interact or activates/ inactivates a target gene.
Target can be identified from:
1. A range of chemical compounds belonging to the same family.
2. Improvising on an existing molecule.
3. Trying out molecular combination of different trusted medicines.
A target compound would have to be screened from a list of minimum 1000 compounds to get approximately 30 viable compounds.
The drug is tested to see whether:
1. It is stable in different environments
2. Performs consistently
3. Has fever adverse effects
4. Doesn't alter metabolic processes too much
5. Reaches the site of action effectively
6. Offer site action instead of acting indiscriminately on other sites in the body.
Monetary gain also influences the drug discovery process. A drug company strives to find a unique molecule so that it could be patented and to know if it will provide better results on large scale manufacturing.