Retinoid receptor agonists for promoting hair growth and/or retarding hair loss

A cosmetic or therapeutic composition of matter suited for at least one of inducing or stimulating hair growth and retarding hair loss, comprising an effective amount of at least one RXR-type retinoid receptor agonist, formulated into a cosmetically or therapeutically acceptable vehicle, diluent or carrier therefor wherein said RXR-type retinoid receptor agonist has the following structural formula (I):

• ##STR7## in which Ar is selected from the group consisting of the following substituents:
• ##STR8## wherein the pentagonal heterocycles (ii), (iii), (iv), (v) or (vi) are substituted in position 4 or 5;
• A is --(CH.sub.2).sub.n wherein n ranges from 0 to 5;
• B is --COOH, --COOR.sub.7, --CONR.sub.8 R.sub.9, --CH.sub.2 OH, --CH.sub.2 OR.sub.10, --CH.sub.2 OCOR.sub.10, --CHO, --CH(OR.sub.11).sub.2, --CHOR.sub.12 O, --COR.sub.6, --CR.sub.6 (OR.sub.11).sub.2 or --CR.sub.6 OR.sub.12 O;
• X is an oxygen atom --C(R.sub.5).sub.2 or S(O).sub.m wherein m is 0, 1 or 2;
• R.sub.1 is a hydrogen atom or an alkyl substituent having from 1 to 6 carbon atoms;
• R.sub.2 is a hydrogen atom, an alkyl substituent having from 1 to 6 carbon atoms or a halogen atom;
• the substituents R.sub.3 are identical or different, and are each an alkyl substituent having from 1 to 6 carbon atoms, a halogen atom --OR.sub.10, --SR.sub.10, --OCOR.sub.10, --SCOR.sub.10, --NH.sub.2, --NHR.sub.10, --N(R.sub.10).sub.2, --NHCOR.sub.10 or --NR.sub.10 COR.sub.10 ;
• the substituents R.sub.4 are identical or different, and are each a hydrogen atom, an alkyl substituent having from 1 to 6 carbon atoms, a halogen atom, an alkoxy substituent having from 1 to 6 carbon atoms or a thioalkoxy substituent having from 1 to 6 carbon atoms;
• the substituents R.sub.5 are identical or different and are each a hydrogen atom or an alkyl substituent having from 1 to 6 carbon atoms;
• R.sub.6 is an alkyl substituent having from 1 to 6 carbon atoms, a cycloalkyl substituent having from 3 to 6 carbon atoms or an alkenyl substituent having from 2 to 6 carbon atoms;
• R.sub.7 is an alkyl substituent having from 1 to 10 carbon atoms, a cycloalkyl substituent having from 5 to 10 carbon atoms or a phenyl or lower alkylphenyl substituent;
• the substituents R.sub.8 and R.sub.9 are identical or different, and are each a hydrogen atom, an alkyl substituent having from 1 to 10 carbon atoms, a cycloalkyl substituent having from 5 to 10 carbon atoms, a phenyl substituent or a lower alkylphenyl substituent;
• the substituents R.sub.10 are identical or different, and are each an alkyl substituent having from 1 to 10 carbon atoms, a phenyl substituent or a lower alkylphenyl substituent;
• R.sub.11 is an alkyl substituent having from 1 to 6 carbon atoms;
• and R.sub.12 is a divalent alkylene substituent having from 2 to 5 carbon atoms;
• or one or more optical or geometrical isomers or acyl derivatives or pharmaceutically acceptable salts thereof, and wherein said composition further comprises another hair growth promoter which is not a RXR-type retinoid receptor agonist.