Table 6. Potency and Relative amounts of PTMs in mAb C by LC-MS peptide mapping.
| Storage Temperature | N33D | N33isoD | N33D+N33isoD | Met248 ox | HC pE1 | Potency |
|---|---|---|---|---|---|---|
| Initial |
3.5% |
29.2% |
32.6% |
3.2% |
2.2% |
N/A |
|
1 mo time point | ||||||
| 5°C |
3.4% |
30.3% |
33.6% |
1.4% |
2.5% |
108% |
| 25°C |
5.2% |
44.1% |
49.2% |
1.5% |
2.9% |
101% |
| 40°C |
12.4% |
64.5% |
76.9% |
2.4% |
5.2% |
20% |
|
3 mo time point | ||||||
| 5°C |
3.5% |
26.6% |
30.1% |
3.2% |
1.5% |
96% |
| 25°C |
6.4% |
56.2% |
62.6% |
5.8% |
2.2% |
28% |
| 40°C | 24.1% | 68.5% | 92.6% | 21.7% | 6.1% | 5% |
N33D and N33IsoD refer to relative amount of aspartic acid and isoaspartic acid at position 33, respectively. Total deamidation at position 33 is indicated as the sum of (N33D and N33IsoD). Met248ox refers to methionine oxidation position 248. HC pE1 refers to the proportion of pyroglutamic acid at HC position1. Potency by Binding ELISA is expressed as % of control (Initial, indicated as N/A)