The present invention relates to an agomelatine hydrobromide hydrate of formula I wherein X is Br, preparation and use thereof, and to pharmaceutical compositions containing it. The agomelatine hydrobromide hydrate obtained through the present method has significant increased solubility than agomelatine, and therefore is more suitable for manufacturing pharmaceutical formulations. In addition, the product enjoys higher stability and purity. Using the present method, product of high purity can be obtained through a simple process, free of any complicated steps.
