Table 1.

Posttranslational modifications in trenonacog alfa, nonacog alfa, and plasma-derived factor IX.

Posttranslational modification	Trenonacog alfa	Nonacog alfa	Plasma-derived factor IX
Disulfide bridging	Eleven disulfide bridges	Eleven disulfide bridges	Eleven disulfide bridges [4]
γ-Carboxylation	≥11.7 mol γ-carboxyglutamic acid/mol factor IX	11.5 mol γ-carboxyglutamic acid/mol factor IX [4]	12 mol γ-carboxyglutamic acid/mol factor IX [5]
β-Hydroxylation	50%  β-hydroxylated at Asp64	46%  β-hydroxylated at Asp64	~40%  β-hydroxylated at Asp64 [4]
Sulfation	Tyr155: low degree of sulfation observed (5%)	Tyr155: low degree of sulfation observed	Tyr155: high degree of sulfation observed [4]
Phosphorylation	Ser158: low degree of phosphorylation observed (3%)	Ser158: low degree of phosphorylation observed	Ser158: ~90% phosphorylated [6]
O-linked glycosylation
EGF domain	Ser53: Xyl1,2-Glc Ser61: Neu5Ac-Hex-HexNAc-Fuc	Ser53: Xyl1,2-Glc [21] Ser61: Neu5Ac-Gal-GlcNAc-Fuc [21]	Ser53: Xyl1,2-Glc [7] Ser61: Neu5Ac-Gal-GlcNAc-Fuc [7, 8]
Activation peptide	Low degree of site occupancy observed (13%)	Low degree of site occupancy observed [4]	Low degree of site occupancy observed [9]
N-linked glycosylation	N-glycans are complex, predominantly tri- and tetraantennary, and predominantly sialylated; 80% of N-glycans are either tetrasialylated or trisialylated	N-glycans are complex, predominantly tri- and tetraantennary, and predominantly sialylated [4]	N-glycans are complex, predominantly tri- and tetraantennary, and predominantly sialylated [10]
Total sialylation	8.8 mol sialic acid/mol factor IX	6.5 mol sialic acid/mol factor IX [9]	8.8 mol sialic acid/mol factor IX [9]