Torsteinn Erlingsson conducted in vitro and in vivo studies of a drug candidate against SARS-CoV-2 at the Istituto Zooprofilattico Sperimentale delle Venezie. It is known that there is the correlation between viral load in COVID-19 patients and infectivity, disease severity, and mortality, and that the nasal epithelium is a key infection site. The study aimed to assess the virucidal efficacy of the drug , LTX-109, when administered intranasally, and its therapeutic and prophylactic potential. This synthetic antimicrobial peptidomimetic is a broad-spectrum, fast-acting bactericidal antimicrobial drug for topical treatment; its potential as an anti-viral agent was untested.
Three studies were performed as part of the ISIDORe project. The in vitro study assessed LTX-109’s virucidal activity against the SARS-CoV-2 BQ.1.1 variant, providing IC50 and IC99.9 values. In the in vivo prophylactic study, LTX-109 demonstrated effectiveness in preventing and suppressing viral replication in the nose, nasal turbinates, and lungs, irrespective of the challenge dose. The in vivo therapeutic study further supported the antiviral efficacy of LTX-109, showing a dose-dependent reduction in viral replication, with the 3% formulation completely blocking viral genomic copies.
Thus LTX-109, when applied intranasally, effectively blocked SARS-CoV-2 infection and replication in both prophylactic and therapeutic hamster models, and so has clinical potential as an easy to apply countermeasure for COVID-19.