J Gen Virol

. 2023 Feb;104(2).
doi: 10.1099/jgv.0.001821.
A novel antiviral formulation containing caprylic acid inhibits SARS-CoV-2 infection of a human bronchial epithelial cell model

Kevin Purves 1 , Ruth Haverty 1 , Tiina O'Neill 2 , David Folan 3 , Sophie O'Reilly 4 , Alan W Baird 1 2 , Dimitri Scholz 2 , Patrick W Mallon 4 5 , Virginie Gautier 4 , Michael Folan 3 , Nicola F Fletcher 1 2



A novel proprietary formulation, ViruSAL, has previously been demonstrated to inhibit diverse enveloped viral infections in vitro and in vivo. We evaluated the ability of ViruSAL to inhibit SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) infectivity, using physiologically relevant models of the human bronchial epithelium, to model early infection of the upper respiratory tract. ViruSAL potently inhibited SARS-CoV-2 infection of human bronchial epithelial cells cultured as an air-liquid interface (ALI) model, in a concentration- and time-dependent manner. Viral infection was completely inhibited when ViruSAL was added to bronchial airway models prior to infection. Importantly, ViruSAL also inhibited viral infection when added to ALI models post-infection. No evidence of cellular toxicity was detected in ViruSAL-treated cells at concentrations that completely abrogated viral infectivity. Moreover, intranasal instillation of ViruSAL to a rat model did not result in any toxicity or pathological changes. Together these findings highlight the potential for ViruSAL as a novel and potent antiviral for use within clinical and prophylactic settings.

Keywords: antiviral; caprylate; caprylic acid; coronavirus; enveloped virus; viral envelope.