On both HRV14 (group A) and HRV399, the compound EMEB has definite anti-Rhinovirus activity (group B). The specific activity of Pirodavir used as a positive control is lower than that of Pirodavir, but since the cytotoxic activity of EMEB on human HeLa cells is more beneficial than that of Pirodavir (50 μg/ml vs. 3 μg/ml), the final Safety Index for EMEB is higher (> 700) relative to Pirodavir (250). The criteria for immediate passage to animal trials are available for the current compound EMEB. EMEB appears to be stable in aqueous solutions, as its behaviour was unchanged after 10 days. Even after 18 hours after infection, when EMEB is challanged with HeLa cells infected with Rhinovirus during the whole reproductive cycle, its antiviral activity remains evident and solid. This is significant because it means that even though the viral infection is already in progress, the compound continues to function; this finding makes us hypothesise that the compound EMEB could not only serve as a prophylactic agent against common cold, but also as a therapeutic drug in patients who already display symptoms of the disease (at least within the first 24 hours from the start of symptoms). These last statements must be verified by means of assays on the compound’s mechanism of action, by examining its adhesion to the internalisation of the cell virus into the cells, by viral uncoating, by transcription and translation, and finally by viral morphogenesis. Studies in predictive modelling demonstrate strong potential for considerable further development.
Author (s) Details
Giulio Tarro President of the de Beaumont Bonelli Foundation for Cancer Research, Naples, Italy.