Purified antibody composition

A liquid composition comprising adalimumab, wherein the adalimumab is expressed in a Chinese Hamster Ovary (CHO) cell expression system;

• and wherein the composition is characterized in that when the composition is assayed in a cathepsin L kinetic assay, a level of cathepsin L activity from 0.4 to less than 1.84 RFU/s/mg of adalimumab is observed, wherein the cathepsin L kinetic assay comprises:
• i) diluting the composition in a polystyrene container in a solution containing 25 mM NaOAc, 5 mM DTT and 1 mM EDTA at pH 5.5,
• ii) adding dextran sulfate to a concentration of 0.035 μg/mL and incubating at 37° C. for six hours,
• iii) adding Z-leucine-arginine covalently bound at its C-terminus to a fluorescent 7-amino-4-methyl coumarin (Z-leucine-arginine-AMC), wherein the diluting, adding, and incubating steps are sufficient to permit the measurement of cathepsin L hydrolysis of the Z-leucine-arginine-AMC within a linear range, and
• iv) measuring Z-leucine-arginine-AMC hydrolysis in the linear range in RFU/s/mg of adalimumab.