Purification of antibodies by precipitating impurities using Polyethylene Glycol to enable a two chromatography step process

• Industrial purification of antibodies by precipitation of impurities using PEG is investigated.
• Removal of aggregates, host cell proteins, DNA and virus by precipitation is achieved.
• Optimal precipitation conditions including PEG concentration, pH, temperature, time and protein concentration are identified.
• A unique application of uncharged polymers as a mobile phase modifier in chromatographic load material is identified.
• A standard precipitation development method and two chromatography step process is developed.

The purification of antibodies by precipitating impurities using Polyethylene Glycol (PEG) was assessed with the objective of developing a two chromatography column purification process. A PEG precipitation method was evaluated for use in the industrial purification of recombinant monoclonal antibodies (MAbs). Effective and robust precipitation conditions including PEG concentration, pH, temperature, time, and protein concentration were identified for several different MAbs. A recovery process using two chromatography steps in combination with PEG precipitation gave acceptable yield and purity levels for IgG1 and IgG4 antibodies with a broad range of isoelectric points (pI). PEG precipitation removed host cell proteins (HCPs), high molecular weight species (HMWS), leached Protein A ligand, and host cell DNA to acceptable levels when run under appropriate conditions, and some endogenous virus removal was achieved.