Deflazacort (DFZ, a prodrug) is well absorbed and rapidly metabolized into the active metabolite 21-hydroxydeflazacort (21-OH DFZ) after oral administration. The aim of this study is to evaluate the pharmacokinetic properties of 21-OH DFZ in healthy Chinese volunteers after a single and multiple oral administration of DFZ tablets under fed condition. Twelve volunteers (six males and six females) were administered a single dose of 6 mg or 12 mg or 24 mg of DFZ in three different periods separately, according to the 3 x 3 Latin square design. Between each administration period there was a washout period of one week. The multiple-dose study of 12 mg dose DFZ per day for 7 consecutive days was started after a 1 w washout period when the single-dose study completed. The pharmacokinetic parameters of 21-OH DFZ after the single oral administration of 6 mg, 12 mg and 24 mg DFZ tablets were as follows: (37.7 +/- 11.6), (61.5 +/- 17.7) and (123 +/- 23) ng x mL(-1) for C(max); (1.90 +/- 0.32), (1.96 +/- 0.27) and (2.13 +/- 0.34) h for t1/2; (96.6 +/- 25.9), (190 +/- 44) and (422 +/- 107) ng x h x mL(-1) for AUC(0-14 h), respectively. After the multiple dose administration, the mean plasma concentration at steady-state C(av) was (7.00 +/- 1.66) ng x mL(-1) and the degree of plasma concentration fluctuation DF was 7.7 +/- 1.2. The results showed that the pharmacokinetic characteristics of 21-OH DFZ in healthy Chinese volunteers were linear over the dose range of 6 to 24 mg. No significant gender differences were found in the pharmacokinetics of 21-OH DFZ in healthy Chinese volunteers. After the multiple dose administration of 12 mg DFZ for 7 d, no accumulation of 21-OH DFZ in healthy Chinese volunteers was observed.
Administration, Oral ; Area Under Curve ; Asian Continental Ancestry Group ; Female ; Healthy Volunteers ; Humans ; Male ; Pregnenediones ; pharmacokinetics ; Tablets

Synchronization of estrus and ovulation are of paramount importance in modern livestock improvement programs. These methods are critical for assisted reproduction technologies, including artificial insemination and embryo transfer, that can increase productivity. In the current study, subcutaneous implants containing norgestomet were placed for long (14 days), medium (9 days), and short (5 days) periods of time in 70 crossbred ewes undergoing fixed-time artificial insemination. The resulting effects on estrus synchronization and conception rates were subsequently evaluated. Among the synchronized ewes, 85.7% (60/70) underwent estrus over a period of 72 h after progestagen treatment ceased. The shortest mean interval between withdrawal of the device and onset of estrus (34.2 +/- 8.9 h) was observed in the G14 days of P4 group (p < 0.05). The conception rate of the G14 days of P4 group was statistically higher than that of the other groups (83.3% vs. 60.9% vs. 47.8%; p < 0.05). In conclusion, 14 days of norgestomet treatment produced higher conception rates and a greater number of pregnancies at the beginning of the breeding season.
Animals ; Drug Implants/therapeutic use ; Estrus Synchronization/drug effects/*methods ; Female ; Fertilization/drug effects ; Insemination, Artificial/methods/*veterinary ; Pregnenediones/administration & dosage/*pharmacology ; Sheep