Therapeutic paints comprising sucralfate gel for treating skin and mucosal lesions

A new therapeutic paint for the topical treatment of orf virus skin infection in sheep is presented in this study. The formulation combines the potent antiviral acyclic nucleoside phosphonate cidofovir (1-(S)-3-hydroxy-2-(phosphonomethoxy)propylcytosine, Vistide®) and the wound healing properties of sucralfate gel (sucrose octasulphate basic aluminum salt). Furthermore, the administration was performed by topical spraying making it suitable for veterinary applications. In this study we present the results of in vitro and in vivo experiments on the therapeutic potential of the spray. In vitro experiments consisted of a physico-chemical characterization of formulation and of delivery device. Experiments demonstrated the necessity of including sodium dihydrogen phosphate in the formulation in order to avoid interaction between the two active ingredients. For in vivo experiments, lambs infected with orf virus were treated with different cidofovir/sucralfate formulations (1% or 0.5% w/w cidofovir + 15%w/w sucralfate) and for comparison with sucralfate gel suspension alone (15% w/w). Results showed that the treatment with both formulations containing cidofovir for four consecutive days resulted in a rapid resolution of the lesions, with scabs containing significantly lower amounts of viable virus when compared with untreated lesions and lesions treated with sucralfate suspension alone.