Patent ID: 7420068

Claim:
A method for the manufacture of crystalline particles of escitalopram oxalate, wherein the ratio between the median particle size and the particle size at the 95% quantile is less than 0.42, comprising the steps of: a) treating a solution comprising escitalopram together with one or more hydroxyl containing impurities with a hydroxyl group scavenger; b) separating the escitalopram from the products resulting from reaction of said hydroxyl containing impurities with said hydroxyl group scavenger; c) optionally transferring the escitalopram into its oxalate salt if the escitalopram is not already in the form of its oxalate salt; d) optionally transferring the escitalopram to a solvent system suitable for the crystallisation process if the escitalopram is not already in such a solvent system; and e) gradually cooling the solution of escitalopram oxalate in said suitable solvent system from a first temperature to a second temperature while maintaining a controlled cooling profile and seeding said solution of escitalopram oxalate by addition of crystals of escitalopram oxalate during said cooling.