EP2119696A1 — 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 pharma-ceutically acceptable acid is selected from the group consisting of maleic acid, citric acid, tartaric acid and L-aspartic acid, optionally filtering the solution; 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.