Heat Inactivation of Host Cell-Derived Enzymes as a Control Strategy for Polysorbate Degradation

Area of Science:

• Biopharmaceutical manufacturing
• Protein chemistry
• Enzyme kinetics

Background:

• Polysorbate degradation is a significant challenge in biotherapeutic formulations.
• Residual host cell-derived enzymes are the primary cause of this degradation.
• Current strategies to mitigate polysorbate degradation are limited.

Purpose of the Study:

• To investigate the potential of using differential thermal stability between host cell enzymes and therapeutic proteins as a control strategy.
• To develop a method for inactivating host cell-derived enzymes without compromising biotherapeutic integrity.

Main Methods:

• Chemical proteomics was used to profile the heat sensitivity of host cell-derived enzyme activity.
• Biophysical studies were conducted to compare the thermal stability of enzymes and a monoclonal antibody.
• A proof-of-concept experiment involved heat treatment of a polysorbate-spiked protein-A pool.

Main Results:

• Phospholipase A2 group VII (PLA2G7) was found to become inactive after brief heat exposure.
• Host cell-derived enzymes exhibited lower thermal stability compared to monoclonal antibodies.
• Mild heat treatment minimally impacted the stability of the monoclonal antibody.
• Heat inactivation of host cell-derived enzymes significantly decelerated polysorbate degradation.

Conclusions:

• Host cell-derived enzymes can be selectively inactivated using mild heat treatment.
• This heat-based inactivation strategy effectively reduces polysorbate degradation in biotherapeutic formulations.
• Selective heat inactivation offers a promising approach for controlling polysorbate degradation and enhancing biotherapeutic stability.