Kinetic Modeling of Methionine Oxidation in Monoclonal Antibodies from Hydrogen Peroxide Spiking Studies.

Unlabelled: When isolator technology is applied to biotechnology drug product fill-finish process, hydrogen peroxide (H2O2) spiking studies for the determination of the sensitivity of protein to residual peroxide in the isolator can be useful for assessing a maximum vapor phase hydrogen peroxide (VPHP) level. When monoclonal antibody (mAb) drug products were spiked with H2O2, an increase in methionine (Met 252 and Met 428) oxidation in the Fc region of the mAbs with a decrease in H2O2 concentration was observed for various levels of spiked-in peroxide. The reaction between Fc-Met and H2O2 was stoichiometric (i.

Site-specific tryptophan oxidation induced by autocatalytic reaction of polysorbate 20 in protein formulation.

Purpose: Tryptophan (Trp) oxidation leading to atypical degradation of a protein (Fab) formulated with polysorbate 20 (PS20) was investigated. Such atypical Trp oxidation was discussed in relation to a kinetic model that involves initiation of oxidizing free radical through an autocatalytic reaction.

Methods: Ion-exchange chromatography and peptide mapping were used to determine Trp oxidation.