Thomasy Sara M, Whittem Ted, Bales Jerry L, Ferrone Marcus, Stanley Scott D, Maggs David J
Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA.
Am J Vet Res. 2012 Jul;73(7):1092-9. doi: 10.2460/ajvr.73.7.1092.
To investigate the pharmacokinetics of penciclovir in healthy cats following oral administration of famciclovir or IV infusion of penciclovir.
6 cats.
Cats received famciclovir (40 [n = 3] or 90 [3] mg/kg, PO, once) in a balanced crossover-design study; the alternate dose was administered after a ≥ 2-week washout period. After another washout period (≥ 4 weeks), cats received an IV infusion of penciclovir (10 mg/kg delivered over 1 hour). Plasma penciclovir concentrations were analyzed via liquid chromatography-mass spectrometry at fixed time points after drug administration.
Mean ± SD maximum plasma concentration (C(max)) of penciclovir following oral administration of 40 and 90 mg of famciclovir/kg was 1.34 ± 0.33 μg/mL and 1.28 ± 0.42 μg/mL and occurred at 2.8 ± 1.8 hours and 3.0 ± 1.1 hours, respectively; penciclovir elimination half-life was 4.2 ± 0.6 hours and 4.8 ± 1.4 hours, respectively; and penciclovir bioavailability was 12.5 ± 3.0% and 7.0 ± 1.8%, respectively. Following IV infusion of penciclovir (10 mg/kg), mean ± SD penciclovir clearance, volume of distribution, and elimination half-life were 4.3 ± 0.8 mL/min/kg, 0.6 ± 0.1 L/kg, and 1.9 ± 0.4 hours, respectively.
Penciclovir pharmacokinetics following oral administration of famciclovir were nonlinear within the dosage range studied, likely because of saturation of famciclovir metabolism. Oral administration of famciclovir at 40 or 90 mg/kg produced similar C(max) and time to C(max) values. Therefore, the lower dose may have similar antiviral efficacy to that proven for the higher dose.
研究口服泛昔洛韦或静脉输注喷昔洛韦后，喷昔洛韦在健康猫体内的药代动力学。
6只猫。
在一项平衡交叉设计研究中，猫接受泛昔洛韦（40 [n = 3] 或90 [3] mg/kg，口服，一次）；在≥2周的洗脱期后给予另一剂量。在另一个洗脱期（≥4周）后，猫接受静脉输注喷昔洛韦（10 mg/kg，输注1小时）。给药后在固定时间点通过液相色谱 - 质谱法分析血浆喷昔洛韦浓度。
口服40和90 mg泛昔洛韦/kg后，喷昔洛韦的平均±标准差最大血浆浓度（C(max)）分别为1.34 ± 0.33 μg/mL和1.28 ± 0.42 μg/mL，分别在2.8 ± 1.8小时和3.0 ± 1.1小时出现；喷昔洛韦消除半衰期分别为4.2 ± 0.6小时和4.8 ± 1.4小时；喷昔洛韦生物利用度分别为12.5 ± 3.0%和7.0 ± 1.8%。静脉输注喷昔洛韦（10 mg/kg）后，喷昔洛韦的平均±标准差清除率、分布容积和消除半衰期分别为4.3 ± 0.8 mL/min/kg、0.6 ± 0.1 L/kg和1.9 ± 0.4小时。
在所研究的剂量范围内，口服泛昔洛韦后喷昔洛韦的药代动力学是非线性的，可能是由于泛昔洛韦代谢饱和所致。口服40或90 mg/kg泛昔洛韦产生相似的C(max)和达到C(max)的时间值。因此，较低剂量可能具有与较高剂量已证实的抗病毒疗效相似的效果。
