Peroxide Residual and Oxidation of mAb3 Formulation (200 mg/mL) Spiked with Various Concentrations of H2O2 at 5 °C Storage
| Assay | Time (months) | H2O2 Concentration (ng/mL) | ||||
|---|---|---|---|---|---|---|
| 0 (control) | 100 | 500 | 1000 | 7000 | ||
| Amplex® UltraRed HRP Assay—Peroxide (ng/mL) | 0 | <LOD | 108 | 558 | 1190 | 7648 |
| 0.25 | 22 | 37 | 90 | 218 | 1727 | |
| 0.5 | <LOD | <LOD | 21 | 45 | 402 | |
| 1 | <LOD | <LOD | <LOD | <LOD | 28 | |
| 2 | NT | NT | <LOD | <LOD | <LOD | |
| 3 | NT | NT | NT | NT | <LOD | |
| Peptide Mapping—UHPLC | ||||||
| % Met 252 Oxidation | 0 | 2.7 | NT | NT | NT | NT |
| 1 | 3.3 | 3.2 | 3.2 | 3.2 | 7.5 | |
| 2 | 3.5 | 3.5 | 3.7 | 4.0 | 8.0 | |
| 3 | 3.8 | 3.6 | 3.6 | 3.6 | NT | |
| % Met 428 Oxidation | 0 | 2.1 | NT | NT | NT | NT |
| 1 | 2.3 | 2.3 | 2.6 | 2.6 | 4.7 | |
| 2 | 1.7 | 1.7 | 1.9 | 1.9 | 4.8 | |
| 3 | 2.6 | 2.5 | 2.5 | 2.7 | NT | |
UHPLC, ultra-high-performance liquid chromatography; HRP, horseradish peroxidase; LOD, limit of detection; NT, not tested.