Antiparasitics: veterinary research with human impact

The 2015 Nobel Prize in physiology or medicine was given to three researchers whose scientific careers were devoted to the fight of parasitic diseases. Two of them, the Japanese microbiologist Satoshi Ōmura and the Irish biologist William Campbell, were awarded for the discovery and development of a new class of drug known as avermectin, whose main exponent is ivermectin drug.

Adrián Luis Lifschitz, CONICET independent researcher at the Centro de Investigación Veterinaria de Tandil (CIVETAN, UNCPBA-CONICET-CICPBA) [Veterinary Research Centre of Tandil] explains the importance of the findings and its contributions to the parasitic infections therapeutics.

What was the relevance of the discovery made by Satoshi Ōmura and William Campbell?

Ivermectin was developed to be used in veterinary medicine and was launched into the market in 1981. Since then, it has become a best-selling drug in the history of veterinary medicine due to its effective action against internal parasites such as roundworms in different parts of the body; and external, like the ticks, lice and scabies mites. This introduction of this drug is considered as a turning point in the history of therapeutics in animal health. The impact of the use of that drug in human medicine contributed to fight onchocerciasis, also called “river blindness”, which produces lymphatic filariasis, which affects millions of people in different parts of the world. Due to the importance of this drug, the 2015 Nobel Prize was awarded to the above mentioned researchers. It is worth mentioning that all initial studies of development and characterization of the drug properties have been conducted in animals since veterinary research.

Are there any studies about this drug in our country?

For many years, with the use of ivermectin and its derivatives as models for parasitology-drugs research in domestic animals, scientists have carried out research at the Laboratorios de Parasitología y Farmacología [Laboratory of Parasitology and Pharmacology] of the CIVETAN, in Tandil, Argentina. These studies have contributed to the scientific knowledge available on this type of drug. We have provided pharmacologically- based scientific data that demonstrated the distinctive features of these antiparasitic drugs , thus improving the knowledge on their pharmachological potency, pharmacokinetics patterns, absorption, tissue distribution, and great affinity for tissue lipid nature, what supports its prolonged activity on parasitic organisms of different types. Furthermore, in the last stage we have worked on the interpretation of the mechanisms of resistance to ivermectin and how the pharmacological modulation of cell transport mechanism can promote the activity of this molecule. An example of this is the fact that a great number of scientific studies conducted at the CIVETAN have been published in more than 40 international journals, which led to at least six doctoral thesis on the specific subject of the 2015 Nobel Prize in physiology or medicine. For this reason, this centre is currently considered as an international reference centre in that subject.

What is the future approach of these drugs?

We are currently looking for rational strategies for the use of these drgus due to the advances of parasite resistance to these drugs, particularly in veterinary medicine. Considering the special features of the ivermectin and its derivatives, we think that it is going to be difficult to have drugs with similar characteristics in the short term, making the rational use of those ones more relevant. We can conclude that once more it is possible to show how basic research into Veterinary Medicine can provide biomedical knowledge with direct impact on the preservation of animal and human health and improvements in the quality of life of the people.