Famvir (famciclovir) contains famciclovir, an orally administered prodrug of the antiviral agent penciclovir. Chemically, famciclovir is known as 2-[2-(2-amino-9H-purin-9-yl)ethyl]-1,3-propanediol diacetate.
Famciclovir is a white to pale yellow solid. It is freely soluble in acetone and methanol, and sparingly soluble in ethanol and isopropanol. At 25?C famciclovir is freely soluble ( > 25% w/v) in water initially, but rapidly precipitates as the sparingly soluble (2%-3% w/v) monohydrate. Famciclovir is not hygroscopic below 85% relative humidity. Partition coefficients are: octanol/water (pH 4.8) P=1.09 and octanol/phosphate buffer (pH 7.4) P=2.08.
Tablets for Oral Administration
Each white, film-coated tablet contains famciclovir. The 125-mg and 250-mg tablets are round the 500-mg tablets are oval. Inactive ingredients consist of hydroxypropyl cellulose, hydroxypropyl methylcellulose, lactose, magnesium stearate, polyethylene glycols, sodium starch glycolate and titanium dioxide.
Famvir? (famciclovir) is indicated for the treatment of acute herpes zoster (shingles). Herpes Simplex Infections
Famvir is indicated for:
* treatment or suppression of recurrent genital herpes in immunocompetent patients.
* treatment of recurrent herpes labialis (cold sores) in immunocompetent patients.
* treatment of recurrent mucocutaneous herpes simplex infections in HIV-infected patients.
The safety of Famvir? (famciclovir) has been evaluated in clinical studies involving 816 Famvir-treated patients with herpes zoster (Famvir, 250 mg t.i.d. to 750 mg t.i.d.) 163 Famvir-treated patients with recurrent genital herpes (Famvir, 1000 mg b.i.d.) 1,197 patients with recurrent genital herpes treated with Famvir as suppressive therapy (125 mg q.d. to 250 mg t.i.d.) of which 570 patients received Famvir (open-labeled and/or double-blind) for at least 10 months and 447 Famvir-treated patients with herpes labialis (Famvir, 1500 mg once or 750 mg b.i.d.). Table 5 lists selected adverse events.