Very few drugs have shown an effect against SARS-CoV-2. Much hope remained unfulfilled. But the search continues. An Austro-Hungarian team of scientists has now published the first evidence that azelastine, an antihistamine that has been used as a hay fever spray for years, has an effect in cell cultures. The first tests on infected people were also positive.
Robert Konrat from Max Perutz Labs and experts from Calyxha Biotechnologies in Vienna, together with authors from the Institute of Virology of MedUni Innsbruck and Hungarian research centers (e.g. National Laboratory for Virology in Pecs), used a bioinformatics method to search for active pharmaceuticals ingredients that had already been approved, which could potentially be used against Covid-19. This “repurposing” (new application; note) with the extension of the field of application of already known substances would of course have the advantage of already being fully aware of their structure, absorption and degradation, as well as their safety features.
There are already many examples of this in medicine – with substance banks containing many millions of active ingredients in the pharmaceutical industry and many thousands of approved drugs. Drugs that were originally developed as antidepressants and are commonly prescribed are now also used to treat nerve pain. Minoxidil, which was previously intended as a blood pressure medicine, experienced a new “bloom” as an active ingredient against hair loss. It was often coincidence that led to such “repurposing”, but now more targeted attempts are being made on the basis of substance structure models and other information.
New approach to use known remedy
The group of scientists’ experiment, as they describe it in Frontiers of Pharmacology (DOI: 10.3389/fphar.2022.861295): “We used a novel computational approach to search between approved and commercially available drugs. (…) The predicted antiviral activity of one of these agents, azelastine, has been tested in the laboratory on Vero E6 cells (cell line derived from green monkey kidney cells; ed.). (…) “The cells were modified to increasingly form the docking site for SARS-CoV-2, the ACE2 enzyme. Laboratory-grown nasal mucosa cells were also used. The cultures were infected with several variants of SARS- CoV-2 (alpha, beta, delta) Then azelastine was added.
Azelastine is a so-called H1-receptor antagonist, which on the one hand inhibits the receptor for the histamine that causes allergy symptoms, and on the other hand stabilizes the antibody-producing mast cells in the context of allergic reactions and also has an anti-inflammatory effect. Azelastine has been used “classically” for years as an active ingredient in nasal sprays for hay fever and anti-allergic eye drops. The research group determined the inhibitory effect of different concentrations on SARS-CoV-2 in the laboratory.
Result promising
The result: “Azelastine reduced the cell-damaging effect and the number of SARS-CoV-2 particles both with preventive (before infection; note) and therapeutic use on the Vero cells (…). Similar efficacy was found for the alpha, beta and delta variants In addition, even a five-fold dilution (0.02 percent azelastine) of a commercially available nasal spray has been shown to be very potent in preventing the virus from multiplying in nasal tissue cultures.”
According to the authors, the antihistamine could possibly be an effective means of preventing colonization of the nasal tract with SARS-CoV-2. The first spray tests on SARS-CoV-2 infected people have already taken place. They “confirmed faster elimination of the virus in SARS-CoV-2 positive people.” Extensive clinical studies would, of course, be required before azelastine could actually be used outside of such scientific studies against SARS-CoV-2. In any case, in the treatment of hay fever, there are millions of experiences with the substance every year. Security and compatibility are certainly no problem.
Source: Krone
I’m Wayne Wickman, a professional journalist and author for Today Times Live. My specialty is covering global news and current events, offering readers a unique perspective on the world’s most pressing issues. I’m passionate about storytelling and helping people stay informed on the goings-on of our planet.
