The chemical substances used in the treatment of human diseases can be derived from animals, microbes, plants and so on. It was during the period between 1970 and 1980 that the use of natural products reached its peak in the western pharmaceutical industry.1
Thus, as a precedent for this scenario influenced by non-synthetic chemical substances, approximately half of the New Molecular Entities (NME) of small molecules introduced between 1981 and 2002 were natural products, analogues of semi-synthetic natural products or synthetic compounds based on natural products.1 new drugs derived from natural products, from 2001 to 2005, introduced for the treatment of bacterial and fungal diseases, cancer, diabetes, dyslipidemia, atopic dermatitis, Alzheimer's disease and genetic diseases.2
Despite this success, pharmaceutical research in natural products has experienced a slow decline in the past two decades where most major pharmaceutical companies have downgraded or even ended their natural products research program.1
It is suspected that this may have occurred for several reasons, such as the long delay between the discovery and the launch of the NME, which normally lasts ten years or more. In addition, the basic technologies used to discover natural products for drug discovery had not evolved substantially to make the discovery rate of medicines derived from natural products meet industry demands.3
The discovery of medicines from natural products has several limitations in comparison to the discovery of synthetic chemical medicines, since natural products are often synthesized in small quantities and present as mixtures in extracts, which require lengthy and laborious purification procedures in addition to having structures complexes that make it difficult to prepare analogs of natural products.3
Taking these aspects into account, it is clear that there are still many resources that can be exploited in researching natural products in the discovery of new drugs since traditional herbal medicines that are used by different cultures have not been fully explored. These new discoveries still require some effort, but progress is expected with the improvement of technology and techniques available on the market today.
References
[1] Koehn, F. E., & Carter, G. T. (2005). The evolving role of natural products in drug discovery. Nature Reviews Drug Discovery, 4(3), 206–220. doi:10.1038/nrd1657
[2] Lam, K. S. (2007). New aspects of natural products in drug discovery. Trends in Microbiology, 15(6), 279–289. doi:10.1016/j.tim.2007.04.001
[3] Harvey, A. L., Edrada-Ebel, R., & Quinn, R. J. (2015). The re-emergence of natural products for drug discovery in the genomics era. Nature Reviews Drug Discovery, 14(2), 111–129. doi:10.1038/nrd4510
Authors: Gabrielle Gimenes and Thamires Carolina @th_carolina
