The present invention is directed to a crystalline compound comprising a hydrobromide acid (HBr) salt of a compound of formula (I) (1-{2-[(2,4-dimethylphenyl)sulfanyl]phenyl}piperazine, INN: vortioxetine), having an XRPD pattern with characteristic peaks (expressed in 2? ± 0,2° 2? (CuKa radiation)) at 5.5°, 14.8°, 16.7° and 20.0° and processes for obtaining the same.