Compositions and methods for stimulating hair growth

A method for stimulating hair growth comprising topically administering a composition comprising:

• at least one penetration enhancer;
• and
• a cyclopentane heptanoic acid, 2-cycloalkyl or arylalkyl compound represented by the formula I:
• wherein the dashed bonds represent the presence or absence of a double bond which can be in the cis or trans configuration, A is an alkylene or alkenylene radical having from two to six carbon atoms, which radical can be interrupted by one or more oxa radicals and substituted with one or more hydroxy, oxo, alkyloxy or alkylcarboxy groups wherein the alkyl radical comprises from one to six carbon atoms;
• B is a cycloalkyl radical having from three to seven carbon atoms, or an aryl radical, selected from the group consisting of hydrogen, a lower alkyl radical having from four to ten carbon atoms wherein the heteroatom is selected from the group consisting of nitrogen, oxygen and sulfur atoms;
• X is —N(R4)2 wherein R4 is selected from the group consisting of hydrogen, a lower alkyl radical having from one to six carbon atoms,
• wherein R5 is a lower alkyl radical having from one to six carbon atoms;
• Z is ═O;
• one of R1 and R2 is ═O, —OH or a—O(CO)R6 group, and the other one is —OH or —O(CO)R6, or R1 is ═O and R2 is H, wherein R6 is a saturated or unsaturated acyclic hydrocarbon group having from 1 to about 20 carbon atoms, or —(CH2)mR7 wherein m is 0 or an integer of from 1 to 10, and R7 is cycloalkyl radical, having from three to seven carbon atoms, or a hydrocarbyl aryl or heteroaryl radical, as defined above in free form or a pharmaceutically acceptable salt thereof, in association with a penetration enhancer in particular formulations adapted for topical application to mammalian skin;
• wherein said composition is formulated for topical administration to the skin.