Penciclovir

Absorption

Measurable penciclovir concentrations were not detected in plasma or urine of healthy male volunteers (n= 12) following single or repeat application of the 1% cream at a dose of 180 mg penciclovir daily.

Toxicity

Symptoms of overdose include headache, abdominal pain, increased serum lipase, nausea, dyspepsia, dizziness, and hyperbilirubinemia.

Description

Vectavir was launched in the UK for herpes labialis. Penciclovir is synthetically available by two routes of four steps each from 2- (hydroxymethyl)butane-l,4-diol and is active against HSV-1, HSV-2 VZV but has limited activity against CMV. Vectavir is an acyclic guanosine analog that acts as a competitive inhibitor of DNA polymerase. It is a metabolic product of famcyclovir that is preferentially phosphorylated by viral infected cells (by thymidine kinases) over normal cells. The triphosphate has a low activity against cellular DNA polymerase which is one possible explanation for its low toxicity. While its spectrum of activity is similar to acyclovir, it is longer acting because its triphosphate is 20 times more stable and is not metabolized.

The Uses of Penciclovir

A deuterated version of Penciclovir, an antiviral

Background

Penciclovir is a synthetic acyclic guanine derivative with antiviral activity used for the treatment of various herpes simplex virus (HSV) infections. Displaying low toxicity and good selectivity, penciclovir is a nucleoside analogue.

Indications

Used to treat recurrent cold sores on the lips and face from various herpesvirus invections.

What are the applications of Application

Penciclovir is a purine acyclic nucleoside analogue with potent antiviral activity

Pharmacokinetics

Penciclovir is the active metabolite of the oral product famciclovir. The more favorable results observed with topical penciclovir versus topical acyclovir for the treatment of herpes labialis may be due to the longer intracellular half-life of penciclovir in HSV-infected cells. The activated drug inhibits the viral DNA polymerase. This impairs the ability of the virus to replicate within the cell.

Metabolism

Hepatic