Typical Late-Stage DS Specification Tests and Specifications (Intended Use)
| Test Method | Possible Method Status | Example DS Specifications |
|---|---|---|
| Appearance | Compendia | Practically free from visible particles |
| Total protein | APT | nominal value ± 10.0% |
| cIEF | (Potential) APT | Peak pattern consistent with Reference Standard; Monomer: NLT 65%; Total acidic peaks: NMT 30%; Total basic peaks; NMT 10% |
| MoA-simulated bioassaya | Validated | 90%–120% (symmetrical) of Reference Standard binding; 90%–125% (geometrical) of Reference Standard binding |
| Reducing gel electrophoresis | APT | Area percent purity of heavy + light chains: NLT 98.5%; Total area percent of impurities: NMT 1.5% |
| Non-reducing gel electrophoresis | APT | Major product peak: NLT 98.5%; Total area percent of impurities: NMT 1.5% |
| HPSEC | APT | Major product peak: NLT 98.3%; Aggregates: NMT 1.7%; Fragments: NMT 1.7% |
| Host cell DNA | APT | LT 20 pg DNA/mg protein |
| CHO host cell protein | APT | NMT 20 ng/mg protein |
| Protein A | APT | NMT 10 ng/mg protein |
| Bioburden | Compendia | NMT 10 CFU per 100 mL |
| Endotoxin (LAL) | Compendia | NMT 0.20 EU/mg protein (or reported in EU/mL) |
Note: APT, analytical platform technology; CFU, colony-forming units; DNA, deoxyribonucleic acid; DP, drug product; DS, drug substance; cIEF, capillary isoelectric focusing; HPSEC, high-performance size-exclusion chromatography; LAL, limulus amebocyte lysate; LT, less than; MoA, mode of action; NLT, not less than; NMT, not more than.
↵a In this bioassay specification example, the DS is stored frozen whereas the DP is stored at 2°C–8°C. The DP specifications (80%–120% or 80%–125% for a geometrical specification range) include the consideration of a maximum expected potency loss of 10% upon DP storage.