Patent ID: 8802816
Filing Date: 2014-08-12
Classification: C07K

Abstract:
1. A process of obtaining a recombinant insulin glargine having purity of at least 96% and containing less than 1% glycosylated impurity by a yeast expression system, said process comprising steps of: a) culturing b) recovering the yeast expressed insulin glargine precursor, said recovering comprises separating the insulin glargine precursor from the yeast to obtain a recovered insulin glargine precursor preparation; c) optionally subjecting the recovered preparation of step (b) to a step of crystallization, d) subjecting the recovered preparation of step (b) or crystals of step (c) to enzymatic conversion at pH ranging from about 6 to about 10, in presence of trypsin or trypsin like enzyme and water miscible organic solvent in the concentration ranging from about 40% to about 60%, to obtain insulin glargine containing at least one related impurity; e) purifying said insulin glargine containing at least one related impurity, said purifying comprises contacting the said insulin glargine with a RP-HPLC chromatographic matrix wherein multiple purification steps are carried out by employing: f) precipitating the purified insulin glargine of step (e) by adding a combination of citric acid buffer and zinc chloride at pH ranging from about 6 to about 8 to obtain the insulin glargine having purity of at least 96% and containing less than 1% glycosylated impurity.