Table 1.
Pharmacokinetic parameters of metformin SPLA, SPO and SIV from healthy rabbits after single oral administration of 5 mg/kg body weight to rabbits. Results are presented as the means ± SD (n = 5)
| Parameter | IV solution | Oral solution | Oral microparticles |
|---|---|---|---|
| Cmax (µg/mL) | - | 3.19 ± 0.16 | 1.36 ± 0.05 |
| Tmax (min) | - | 110.5 ± 2.37 | 138.94 ± 4.73 |
| T1/2 (min) | 139.61 ± 4.39 | 153.78 ± 4.19 | 223.30 ± 21.30 |
| AUC0-inf (µg/mL/min) | 2440.77 ± 68.71 | 882.85 ± 23.90 | 617.88 ± 12.92 |
| AUC0-last (µg/mL/min) | 2271.93 ± 64.68 | 693.36 ± 21.93 | 512.89 ± 9.68 |
| AUC360 min (µg/mL/min) | 2271.93 ± 64.68 | 693.36 ± 21.93 | 340.56 ± 9.68 |
| % AUClast-inf (µg/mL/min) | 6.37 ± 0.48 | 15.08 ± 0.96 | 16.2 ± 1.23 |
| AUMC0-∞ (µg/mL/min) | 370,257.81 ± 8667.42 | 176,590.56 ± 6288.57 | 220,874.35 ± 7235.63 |
| VZ (mL/kg) | 380.81 ± 22.44 | 881.45 ± 52.16 | 2494 ± 212.37 |
| VSS (mL/kg) | 315.55 ± 16.64 | 1445.82 ± 52.24 | 2912.23 ± 199.58 |
| Cl (mL/min/kg) | 0.830 ± 30.1 | 0.850 ± 23.57 | 0.330 ± 20.16 |
| MRT (min) | 117.73 ± 1.88 | 165.1 ± 1.53 | 255.53 ± 1.9 |
| MAT (min) | - | 63.66 ± 2.13 | 208.28 ± 31.86 |
| F (%) | - | 30.74 ± 1.56 | 22.59 ± 0.69 |
| F (%)360 min | - | - | 15.51 ± 1.53 |
Cmax Peak or maximum drug concentration following extravascular administration, Tmax Time to reach peak or maximum drug concentration following extravascular administration, T½ Elimination half-life associated with the terminal (log-linear) elimination phase, AUC0-inf Area under the concentration–time curve from zero to infinity, AUC0-last Area under the concentration–time curve from zero to the last observed concentration after SPO administration, % AUClast-inf Percentage of the AUC0-inf that corresponds from the last administration to infinity, the area under the concentration–time curve from zero to the last observed concentration, AUC360 min Area under the concentration–time curve from zero to 360 min, Vz Apparent volume of distribution calculated by the area method, Vss Volume of distribution at steady state, Cl Plasma clearance, MRT Mean residence time, MAT Mean absorption time, F (%) Fraction of the administered dose systemically available (bioavailability), F (%)360 min Bioavailability calculated with AUC360 min as the last point for the last point of the oral solution administration