Table 2.
Characteristics of current hemoglobin-based oxygen carriers in phase III trials
| Characteristic | Hemopure | PolyHeme | RBCs |
|---|---|---|---|
| Hemoglobin (g%) | 13 | 10 | 13 |
| Unit equivalent (g) | 30 | 50 | 50 |
| Molecular weight (>64 kd) | ≥95% | ≥99% | ≥100% |
| P50 (mm Hg) | 38 | 29 | 26 |
| Hill coefficient | 1.4 | 1.7 | 2.7 |
| Oncotic pressure (mm Hg) | 25 | 23 | 25 |
| Viscosity (cp) | 1.3 | 2.1 | (Whole blood 5–10) |
| Methemoglobin (%) | <10 | <8 | <1 |
| Half-life | 19 h | 24 h | 31 d |
| Shelf-life at 4°C | ≥3 y | ≥1.5 y | 42 d |
| Shelf-life at 21°C | ≥2 y | ≥6 wk | ≥6 h |
Abbreviations: cp, Centipoise; P50, Tension when hemoglobin-binding sites are 50% saturated.