Properties of low-molecular–weight heparin (LMWH), fondaparinux and idraparinux.
| Property . | LMWH . | Fondaparinux . | Idraparinux . |
|---|---|---|---|
| Abbreviations: FXa, factor Xa; FIIa, factor IIa; FIXa, factor IXa; FXIa, factor XIa; FXIIa, factor XIIa; SC, subcutaneous; TFPI, tissue factor pathway inhibitor; HIT, heparin-induced thrombocytopenia | |||
| Source | Porcine mucosal heparin | Chemical synthesis | Chemical synthesis |
| Molecular weight (daltons) | Mean 5000 | 1728 | 1727 |
| SC bioavailability | ~ 90% | 100% | 100% |
| Target(s) | Multiple: FXa > FIIa > FIXa, FXIa, FXIIa | FXa only | FXa only |
| Binding to proteins other than target | Yes | No | No |
| Anti-Xa:anti-IIa | 2–5:1 | Anti-Xa only | Anti-Xa only |
| TFPI release from endothelium | Yes | No | No |
| Clearance | Renal primarily | Renal | Renal |
| Half life (SC route) | 3–4 hrs | 17–21 hrs | 80–130 hours |
| Effects of protamine | Partial neutralization | No effect | No effect |
| Potential for HIT | Low | Very low | Very low |
| Property . | LMWH . | Fondaparinux . | Idraparinux . |
|---|---|---|---|
| Abbreviations: FXa, factor Xa; FIIa, factor IIa; FIXa, factor IXa; FXIa, factor XIa; FXIIa, factor XIIa; SC, subcutaneous; TFPI, tissue factor pathway inhibitor; HIT, heparin-induced thrombocytopenia | |||
| Source | Porcine mucosal heparin | Chemical synthesis | Chemical synthesis |
| Molecular weight (daltons) | Mean 5000 | 1728 | 1727 |
| SC bioavailability | ~ 90% | 100% | 100% |
| Target(s) | Multiple: FXa > FIIa > FIXa, FXIa, FXIIa | FXa only | FXa only |
| Binding to proteins other than target | Yes | No | No |
| Anti-Xa:anti-IIa | 2–5:1 | Anti-Xa only | Anti-Xa only |
| TFPI release from endothelium | Yes | No | No |
| Clearance | Renal primarily | Renal | Renal |
| Half life (SC route) | 3–4 hrs | 17–21 hrs | 80–130 hours |
| Effects of protamine | Partial neutralization | No effect | No effect |
| Potential for HIT | Low | Very low | Very low |