H4 receptor inhibitors for treating tinnitus

1. A method for treating tinnitus in a subject, comprising administering to the subject an inhibitor of Histamine type 4 receptor (H4R), wherein said inhibitor of Histamine type 4 receptor (H4R) has a Ki(H3)/Ki(H4) ratio above 10, and wherein said inhibitor of Histamine type 4 receptor (H4R) is selected from the group consisting of 2-aminopyrimidine derivatives, pyrimidine derivatives, quinazoline derivatives, quinazoline sulfonamide compounds, bicyclic heteroaryl-substituted imidazole compounds, thieno-pyrimidine compounds, furo-pyrimidine compounds and mequitazine compounds.

2. The method according to claim 1 , wherein said inhibitor inhibits H4R protein expression and/or activity and/or gene expression.

3. The method according to claim 1 , wherein said inhibitor is a selective inhibitor of H4R.

4. The method according to claim 1 , wherein said inhibitor is a dual antagonist for H1R and H4R or H3R and H4R.

5. The method according to claim 1 , wherein said inhibitor is 1-[(5-chloro-1H-indol-2-yl)carbonyl]-4-methylpiperazine or 4-((3R)-3-Aminopyrrolidin-1-yl)-6,7-dihydro-5H-benzo[6,7]cyclohepta[1,2-d]pyrimidin-2-ylamine or cis-4-(Piperazin-1-yl)-5,6,7a,8,9,10,11,11a-octahydrobenzofuro[2,3-h]quinazolin-2-amine or 7-(furan-2-yl)-4-(piperazin-1-yl)quinazolin-2-amine or 1-(7-(2-amino-6-(4-methylpiperazin-1-yl) pyrimidin-4-yl)-3, 4-dihdroisoquinolin-2(1H)-yl)-2-cyclopentylethanone or 1-[(5-Chloro-1H-benzimidazol-2-yl) carbonyl]-4-methylpiperazine maleate or PF-3893787 or PF-3893787-18 or JNJ39758979 or UR-63325 or 2-isobutyl-6-(3-(methylamino)azetidin-1-yl)pyrimidin-4-amine, or N4-(Cyclopropylmethyl)-6-[(3R)-3-(methylamino)pyrrolidin-1-yl]pyrimidine-2,4-diamine or (R)-4-(3-Amino-pyrrolidin-1-yl)-6-isopropyl-pyrimidin-2-ylamine.