In recent weeks we have heard a lot of talk about a category of drugs that continue to fall short of our needs: antiviral drugs.
There are in fact several types that are effective – for example, those against hepatitis C and AIDS, and we do have vaccines against various infections carried by viruses (such as, papilloma), but there are no antiviral therapies that definitively cure many other diseases, like the illness caused by the coronavirus nCov-2019, not to mention influenza, herpes and many others.
The greatest difficulties, perhaps worth emphasizing, arise from the fact that a virus is not a microorganism like bacteria, but only a strand of the genetic code, wrapped in a protein membrane, which enters the healthy cells of the body and uses them in order to duplicate (and in this way modifies and damages them).
Hence, recognizing and “attacking” a virus becomes much more complex compared to bacteria, as the latter is autonomous and can be combatted using substances like antibiotics, which block their vital mechanisms.
Many research groups worldwide are working on finding more effective solutions against viruses. An international team, involving three European universities – Manchester, Geneva and the Ecole polytechnique fédérale de Lausanne (EPFL) – are focusing on a new and very promising area of study.
As reported in the journal Science Advances, the researchers have discovered that a modified sugar (in particular, a cyclodextrin) can have a powerful antiviral effect, “interrupting” the external membrane of the virus when it comes into contact with it, and hence destroying the pathogenic agent instead of simply restricting its growth. The effect is comparable to the action of products like bleach, which are called virucides because they kill viruses, but which can only be used on objects or be applied externally, as they are too toxic to be in contact with humans.
The sugar or, to be more precise, the class of sugars in question is known as cyclodextrins, to which the researchers added small parts containing derivatives of sulphur. The result is a series of compounds that attract viruses and kill them as soon as they come into contact with them, by depriving them of the external protective capsule, without having any toxic effect on the body.
In addition to this, the modified sugars have another characteristic that immediately attracted the attention of the researchers: they are active against many kinds of viruses, ranging from Respiratory Syncytial Virus to Zika, from viruses of the herpes family to those of hepatitis, from dengue to HIV, and many others. Even if research is still in the very early development stages, the wide-ranging action of these new molecules – according to the researchers – could also be used in the future to fight several strains of the coronavirus.
Caroline Tapparel, lecturer at the University of Geneva and senior author of the study stated, “We have developed a strong molecule that can fight very different viruses. And this could be a game-changer also for emerging infections”.
The tests, which until now have been conducted on human vaginal cells and respiratory tissue, cultivated in the laboratory, and also on animals, have produced excellent results. New research will soon follow.