PURIFICATION OF ANTIBODIES WITH CATION-EXCHANGE CHROMATOGRAPHY Russian patent published in 2013 - IPC C07K1/18 C07K16/06 C07K16/22 C07K16/28 

FIELD: chemistry.

SUBSTANCE: disclosed is a method of purifying antibodies, including human CD20 and VEGF binding antibodies, from a composition which contains an antibody and at least one impurity compound, said method comprising the following steps: (a) loading the composition on a cation-exchange material, where said composition has first pH value from 4.0 to 6.0; (b) washing the cation-exchange material with a first washing buffer at pH higher than that of composition (a), where pH of the first washing buffer ranges from 6.8 to 9.0; (c) washing the cation-exchange material with a second washing buffer at pH lower than that of the first washing buffer; where the second washing buffer has conductivity from 0.5 to 3.0 mS/cm and pH from 5.0 to 6.0; and (d) elution of the antibodies from the cation-exchange material with an elution buffer at conductivity which is at least 2 mS/cm higher than that of the second washing buffer, where pH of the second washing buffer and pH of the elution buffer are approximately equal, and where pH of the elution buffer ranges from 5.0 to 6.0. Described is a conjugation method, which involves conjugating the purified product obtained using said method with a heterologous molecule. Also disclosed is a method of producing a pharmaceutical composition, which involves combining said purified product with a pharmaceutically acceptable carrier.

EFFECT: invention improves purification of antibodies used for treatment.

16 cl, 3 dwg, 4 tbl, 2 ex