Streamlining cation exchange chromatography process development for therapeutic monoclonal antibody purification

Area of Science:

• Biopharmaceutical manufacturing
• Chromatographic purification
• Protein chemistry

Background:

• Cation exchange (CEX) chromatography is vital for removing high molecular weight (HMW) impurities during therapeutic monoclonal antibody (mAb) purification.
• CEX resins offer selectivity and scalability, making them suitable for polishing steps in mAb production.

Purpose of the Study:

• To evaluate five commercial CEX resins for mAb purification.
• To identify optimal resins for superior dynamic binding capacity (DBC), impurity clearance, yield, and robustness.
• To develop a streamlined methodology for CEX process development.

Main Methods:

• Evaluated five CEX resins (Capto S ImpAct, Poros 50 HS, Poros XS, Nuvia HR-S, Eshmuno CPX) using three mAbs.
• Performed pressure flow curve experiments to determine operating velocity.
• Conducted DBC studies to assess column loading capacity.
• Optimized elution conditions using high-throughput screening and linear salt gradients.
• Employed a systematic design of experiments (DOE) for process robustness characterization.
• Utilized a mechanistic model-based approach for process development.

Main Results:

• Poros XS demonstrated superior binding capacity and robustness, outperforming other resins.
• Capto S ImpAct and Eshmuno CPX were identified as comparable alternatives.
• Poros XS achieved high DBC (>100 g/L at 10% breakthrough) at high flow rates (3 min residence time).
• The selected resin effectively reduced HMW species from 5% to 1% with over 90% yield.
• A mechanistic model predicted experimental results with <2% deviation.

Conclusions:

• Poros XS is a leading CEX resin for mAb purification, offering high capacity, efficient HMW impurity removal, and process robustness.
• The study established a streamlined, model-assisted methodology for CEX resin selection and process development.
• This approach enhances efficiency and productivity in biopharmaceutical manufacturing.