Valganciclovir

Valganciclovir hydrochloride (Valcyte, manufactured by Roche) is an antiviral medication used to treat cytomegalovirus infections. As the L-valyl esterases.

Administration

Orally, available in 450 mg pink tablets. Dosing is calculated to provide appropriate doses of ganciclovir; 900 mg of valganciclovir orally every 12 hours is equivalent to 5 mg per kilogram of body weight of intravenous ganciclovir, also every 12 hours.

Pharmacokinetics

1. Oral bioavailability is approximately 60%. Fatty foods significantly increase the bioavailability and the peak level in the serum.
2. It takes about 2 hours to reach maximum concentrations in the serum.
3. Valganciclovir is eliminated as ganciclovir in the urine, with a half-life of about 4 hours in people with normal kidney function.

Side effects

• Blood: neutropenia, anemia, low platelets. Myelosuppression is one of the main side effects that may limit prolonged use of valganciclovir.
• Gastrointestinal: diarrhea, nausea, vomiting, abdominal pain.
• Central nervous system: fever, headache, insomnia, paresthesia, and peripheral neuropathy.
• Ocular: retinal detachment

Alternative uses

It has been proposed that valganciclovir could be used in the treatment of chronic fatigue syndrome, following some reported success in 9 out of 12 patients at Stanford University in California, although further research is required [1]. A study is planned at Stanford for early 2007. [2]

References

1. Kogelnik AM et al Use of valganciclovir in patients with elevated antibody titers against Human Herpesvirus-6 (HHV-6) and Epstein-Barr Virus (EBV) who were experiencing central nervous system dysfunction including long-standing fatigue. J Clin Virol. 2006;37(S1):S33-S38.
2. Paltiel AD et al Preevaluation of clinical trial data: the case of preemptive cytomegalovirus therapy in patients with human immunodeficiency virus. Clin Infect Dis. 2001;32(5):783-93.
3. Pescovitz MD et al Valganciclovir results in improved oral absorption of ganciclovir in liver transplant recipients. Antimicrob Agents Chemother. 2000;44(10):2811-5.
4. Reusser P. Antiviral therapy: current options and challenges. Schweiz Med Wochenschr. 2000;130(4):101-12.
5. Sugawara M, Huang W, Fei YJ, et al. Transport of valganciclovir, a ganciclovir prodrug, via peptide transporters PEPT1 and PEPT2. J Pharm Sci. 2000;89(6):781-9.