US7652012B2 - 2-(r)-(4-Fluoro-2-Methyl-Phenyl)-4-(s)-((8as)-6-Oxo-Hexahydro-Pyrrolo[1,2-A]-Pyrazin-2-Yl)-Piperidine-1-Carboxylic Acid [1-(r)-3,5-Bis-Trifluoromethyl-Phenyl)-Ethyl]-Methylamide Maleate and Pharmaceutical Compositions Thereof