An in vivo pilot study to assess the antiviral efficacy of PA2 phytosome® in pigs experimentally infected with CSFV

none9Classical swine fever (CSF) is responsible of devastating outbreaks with high socio-economic impacts. Since vaccination has been banned in Europe, the current control systems are still based on massive culling of infected and suspect infected animals. Stamping out is considered a cost effective strategy, but it negatively impacts on community acceptance and animal welfare. For this reason use of antiviral drugs has been suggested as additional tool for controlling the spread of CSF as a good alternative to vaccination in offering an immediate protection. In the last few years the efficacy of 5-[(4-Bromophenyl)methyl]-2-phenyl-5H-imidazo[4,5-c]pyridine (BPIP), a representative of a class of imidazopyridines, has been demonstrated in vitro and in vivo. We and others have already demonstrated the efficacy of Proanthocyanidin A2 (PA2) against RNA viruses. In particular, preliminary results showed that this natural compound possesses an extracellular antiviral activity against animal pestiviruses. The aim of this study was to assess in vivo the antiviral activity of Proanthocyanidin A2 in the phytosome form, against CSFV. This formulation demonstrated greater affinity for the epithelial stratum corneum compared to the pure molecule itself, with the potential to enhance PA2 absorption through digestive mucosa. Specific-pathogen-free pigs (n=4) received a PA2 daily dose of 100 mg/kg (dry powder directly mixed in feed) for 15 consecutive days, starting 1 day before infection with the CSFV Alfort/187 strain. Pigs receiving PA2-free feed (n=4) were infected and housed in a separate isolation pen as a positive-control group. Treated pigs showed significantly lower clinical signs and a lower viral genome load compared to the controls. Such results seem to indicate that PA2 phytosome is able to reduce CSFV spread and suggest that it might be simply added to feed, thus being suitable to treat large numbers of animals in case of outbreak to exert either prophylactic and therapeutic effects.mixedA. Scagliarini; S. Petrini; G. Colombo; F. Turrini; L. Gallina; E. Bombardelli; M. Giammarioli; E. Rossi; G.M. De Mia;A. Scagliarini; S. Petrini; G. Colombo; F. Turrini; L. Gallina; E. Bombardelli; M. Giammarioli; E. Rossi; G.M. De Mia