EP2119695A1 — Preparation of O-desmethylvenlafaxine salts

USPTO Abstract

The present invention relates to a process for the preparation of a salt of O-desmethylvenlafaxine comprising a) dissolving or suspending O-desmethylvenlafaxine in the form of its base in a liquid medium selected from the group of solvents and suspending agents; b) contacting O-desmethylvenlafaxine with a pharmaceutically acceptable acid to form a pharmaceutically acceptable salt of O-desmethylvenlafaxine wherein the pharmaceutically acceptable acid is selected from the group consisting of HCl, HBr, H 2 SO 4 , H 3 PO 4 acetic acid, adipic acid, galactaric acid, D-gluconic acid, glutamic acid, glutaric acid, glycolic acid, hippuric acid, lactic acid, oxalic acid, methanesulphonic acid, ethanesulphonic acid, p-toluenesulphonic acid, camphorsulphonic acid, benzenesulphonic acid, malonic acid, L-ascorbic acid, naphtalene-2-sulfonic acid and benzoic acid; and c) separating the pharmaceutically acceptable salt of O-desmethylvenlafaxine from the liquid medium to recover the salt, and to pharmaceutical formulations containing these salts.