The present invention discloses a liquid precursor composition adapted for application on a on a desired surface, this composition comprising: a. at least one therapeutic agent suitable for the treatment or prevention of a disorder or pathological condition, wherein said disorder or pathological condition excludes oral disorders, b. at least one acidic-pH sensitive polymer, c. at least one hydrophobic polymer, and d. a pharmaceutically acceptable volatile solvent, wherein a weight ratio between the at least one hydrophobic polymer and the at least one acidic-pH sensitive polymer is larger than 1.