Table 5.
Pharmacokinetic non-compartmental results of rifampicin in children above and below 4 years of age
| Rifampicin | <4 years old | >4 years old | % difference |
|---|---|---|---|
| Number of patients enrolled | 64 | 36 | |
| Body Weight (median kg - range) | 9.0 (4.0–15.0) | 19.0 (13.5–43.0) | |
| Age (median months - range) | 12 (2–48) | 96 (48–180) | |
| Dosage (mean - % CV) | 9.38 (12.8) | 10.2 (9.04) | p-value: 0.0002a |
| CMAX (ug/mL) | 4.9 | 5.96 | −17.8 |
| TMAX (hr) | 2 | 3 | −33.3 |
| CL/F (L/hr) | 4.66 | 7.86 | −40.7 |
| CL/F/BW (L/hr/kg) | 0.52 | 0.41 | 26.8 |
| V/F (L) | 15.6 | 25.5 | −38.9 |
| V/F/BW (L/kg) | 1.73 | 1.34 | 29.1 |
| T1/2 (hr) | 2.31 | 2.25 | 2.67 |
| AUC0-∞ (hr × ug/mL) | 21.5 | 25.4 | −15.7 |
| AUC0-∞/dosage (hr × ug/mL/(mg/kg)) | 2.36 | 2.6 | −9.23 |
| T > MIC (hr) | 6.89 | 6.66 | 3.45 |
| T > MIC/24 h (%) | 28.7 | 27.8 | 3.39 |
| AUC0–24 h > MIC (hr × ug/mL) | 11.7 | 14.7 | −20.1 |
Apart for dosage with mean and % CV, all values are reported as median (range) or as median estimates for pharmacokinetic parameters. C MAX maximum observed plasma concentration after oral administration, T MAX observed time to reach CMAX, CL/F oral elimination clearance, CL/F/BW elimination clearance corrected by the median body weight, V/F apparent volume of distribution, V/F/BW apparent volume of distribution corrected by the median body weight, T 1/2 terminal elimination half-life, AUC 0-∞ predicted area under the plasma concentration-time curve after the last dose from zero time to infinity, T > MIC time above the minimum inhibitory concentration, T > MIC/24 h percentage of the time above the minimum inhibitory concentration over the 24 h dose interval, AUC > MIC observed area under the plasma concentration-time curve above the minimum inhibitory concentration. % difference is calculated with the > 4 years group used as the reference. aMann–Whitney T-test