Improved penetrating topical pharmaceutical compositions

Claim 1

A penetration-enhancing pharmaceutical composition for topical application characterized in that it comprises: (a) a safe and effective amount of a hydroxy iminopyrimidine compound having the formula wherein R₂ and R₃ are selected from hydrogen, lower alkyl, lower alkenyl, lower aralkyl, and lower cycloalkyl, and taken together R₂ and R₃ may be a heterocyclic moiety selected from aziridinyl, azetidinyl, pyrrolidinyl, piperidine, hexahydroazepinyl, heptamethylenimino, octamethylenimino, morpholino, and 4-lower alkyl piperazinyl, each of said heterocyclic moieties having attached as substituents on the carbon atoms 0-3 lower alkyl groups, hydroxy or alkoxy, and wherein R₁ is selected from hydrogen, lower alkyl, lower alkenyl, lower alkoxyalkyl, lower cycloalkyl, lower aryl, lower aralkyl, lower alkaryl, lower alkaralkyl, lower alkoxyaralkyl, and lower haloaralkyl, and pharmaceutically acceptable acid addition salts thereof; (b) 0% to 90% by weight of a solvent selected from water, ethanol or 2-propanol; and (c) 5% to 99.9% by weight of a penetration-enhancing carrier consisting essentially of: (i) a small polar solvent selected from 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, C₃-C₆ triols, or mixtures thereof, and (ii) a polar lipid compound selected from C₁₆ mono-unsaturated alcohols, C₁₆ branched chain saturated alcohols, C₁₈ mono-unsaturated alcohols, C₁₈ branched chain alcohols, and mixtures thereof; wherein said small polar solvent and said polar lipid compound are present in a ratio of solvent: polar lipid compound of from 1:1 to 500:1, preferably from 5:1 to 100:1 by weight.