Table 1.
Pharmacokinetic parameters of testosterone and its metabolites after oral dose of testosterone at 200 and 800 mg with and without dutasteride
| PK Parameter | Dose group | Testosterone | TG | DHT | AED | A | AG | Etio | EtioG |
|---|---|---|---|---|---|---|---|---|---|
| t1/2 (h) | T200 | 12.0 | 4.4 | 17.6 | 12.7 | 15.6 | 4.9 | 19.0 | 5.2 |
| T200+D | 7.0 | 4.3 | 24.0 | 8.3 | 15.2 | 4.5 | 11.3 | 10.5 | |
| T800 | 5.3 | 3.6 | 6.9 | 6.8 | 8.2 | 4.5 | 10.7 | 7.8 | |
| T800+D | 5.7 | 2.7 | 17.9 | 5.2 | 16.1 | 6.3 | 6.4 | 9.9 | |
| Tmax (h) | T200 | 4 | 2 | 2 | 2 | 2 | 6 | 2 | 2 |
| T200+D | 4 | 4 | 4 | 2 | 2 | 4 | 2 | 4 | |
| T800 | 4 | 1 | 2 | 1 | 2 | 4 | 1 | 1 | |
| T800+D | 2 | 2 | 4 | 2 | 2 | 4 | 2 | 2 | |
| Cmax (nmol/L) | T200 | 6.0 | 149.3 | 2.0 | 66.3 | 11.0 | 1404.4 | 1.2 | 266.9 |
| T200+D | 8.8 | 64.5 | 0.8 | 199.7 | 5.6 | 372.2 | 3.5 | 414.3 | |
| T800 | 16.8 | 1937.3 | 8.4 | 280.5 | 168.5 | 5649.1 | 12.4 | 1129.4 | |
| T800+D | 33.0 | 1174.1 | 1.8 | 2301.9 | 13.0 | 1346.5 | 33.9 | 2096.4 | |
| AUC0–24h (nmol/L*h) | T200 | 81.6 | 857.2 | 26.5 | 373.7 | 96.8 | 12110.8 | 11.2 | 2160.4 |
| T200+D | 84.7 | 373.4 | 9.6 | 1634.9 | 68.5 | 2582.7 | 24.4 | 3277.3 | |
| T800 | 168.9 | 14163.0 | 87.4 | 1551.8 | 1218.9 | 65427.8 | 91.7 | 14981.5 | |
| T800+D | 293.8 | 8589.7 | 26.6 | 10844.4 | 161.5 | 14867.7 | 220.2 | 27091.7 | |
| V/F_obs (L) | T200 | 110034 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ |
| T200+D | 72890 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | |
| T800 | 118392 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | |
| T800+D | 72597 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | |
| Cl/F_obs (L/h) | T200 | 6351 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ |
| T200+D | 7202 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | |
| T800 | 15528 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | |
| T800+D | 8831 | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ | ‐ |
A, androsterone; AED, androstenedione; AG, androsterone glucuronide; AUC, area under the curve; Cmax, peak plasma concentration; DHT, 5α‐dihydrotestosterone; Etio, etiocholanolone; EtioG, etiocholanolone glucuronide, t1/2, terminal half‐life; TG, testosterone glucuronide, Tmax, time of maximum plasma concentration.