Valacyclovir  (Synonyms: 伐昔洛韦; Valaciclovir)

Valacyclovir (Valaciclovir) is an orally active antiviral agent for herpes simplex, herpes zoster, and herpes B. Valacyclovir inhibits HSV-1 W (₅₀=2.9 μg/ml). Valacyclovir is a proagent of Aciclovir (HY-17422) ^{[1][2][3][4][5]}.

Valacyclovir (Valaciclovir; VACV) uptake was concentration dependent and saturable with a Michaelis-Menten constant and maximum velocity of 1.64 mM and 23.34 nmol/mg protein/5 min, respectively. A very similar Km value was obtained in hPEPT1/CHO cells and in rat and rabbit tissues and Caco-2 cells, suggesting that hPEPT1 dominates the intestinal transport properties of VACV in vitro^[5].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

For treatment of a first episode of genital herpes, a large comparative trial has shown that Valacyclovir (1 g twice a day) is as effective as acyclovir (200 mg five times a day) when given for 10 days. For treating recurrences, two trials show that valacyclovir is as effective as acyclovir (200 mg five times a day) with a treatment period of 5 days. A daily dose of 1 g of valacyclovir is as effective as 2 g daily. Valacyclovir can be administered once a day^[1].
The concentrations of acyclovir in serum and CSF were measured at steady state after 6 days of oral treatment with 1,000 mg of valacyclovir three times a day^[2].
EC50 values of PE and AC in 3T3 cells were 0.02 and 0.01 ug/ml, while values in BHK cells were 0.2 and 0.03 ug/ml. Treatment of infected immunosuppressed mice and FA and VA (b.i.d., 5.5 days) reduced the proportion with erythema from 100% to 24% and 38%, and eliminated ear paralysis, ear lesions (vesicles, etc) and death. Virus was absent from ear and brainstem by day 6, but reappeared after discontinuation in mice treated with VA^[3].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

324.34

C₁₃H₂₀N₆O₄

124832-26-4

伐昔洛韦；万乃洛韦

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Valacyclovir. New indication: for genital herpes, simpler administration. Can Fam Physician. 1999 Jul;45:1698-700, 1703-5.  [Content Brief]

  [2]. Lycke J, et al. Acyclovir levels in serum and cerebrospinal fluid after oral administration of valacyclovir. Antimicrob Agents Chemother. 2003 Aug;47(8):2438-41.  [Content Brief]

  [3]. Comparison of efficacies of famciclovir and valaciclovir against herpes simplex virus type 1 in a murineimmunosuppression model. Antimicrob Agents Chemother. 1995 May;39(5):1114-9.  [Content Brief]

  [4]. Dhaliwal DK, Romanowski EG, Yates KA, Valacyclovir inhibits recovery of ocular HSV-1 after experimental reactivation by excimer laser keratectomy. Cornea. 1999 Nov;18(6):693-9.  [Content Brief]

  [5]. Guo A, Hu P, Balimane PV, Interactions of a nonpeptidic drug, valacyclovir, with the human intestinal peptide transporter (hPEPT1) expressed in a mammalian cell line.J Pharmacol Exp Ther. 1999 Apr;289(1):448-54.  [Content Brief]