Preservative system for topically administrable pharmaceutical compositions containing a fatty acid/amino acid soap

A preserved topically administrable pharmaceutical composition comprising a preservative system wherein the preservative system consists essentially of

• i) at least one fatty acid/amino acid soap having a fatty acid component derived from a C8-C24 fatty acid and an amino acid component selected from the group consisting of lysine and arginine;
• ii) one or more pharmaceutically acceptable antifungal acids selected from the group consisting of boric acid;
• benzoic acid;
• salicylic acid;
• sorbic acid;
• lactic acid;
• acetic acid;
• and pharmaceutically acceptable salts thereof;
• and
• iii) one or more pharmaceutically acceptable chelating agents selected from the group consisting of ethylene diamine tetraacetic acid;
• ethylene glycol-bis-(b-aminoethylether)-N,N,N′,N′-tetraacetic acid;
• 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid;
• ethylene-N,N′-diglycine;
• 2,2′-(ethylendiimino)-dibutyric acid;
• and pharmaceutically acceptable salts thereof.