Valganciclovir

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Valganciclovir
Clinical data
Trade namesValcyte
AHFS/Drugs.comMonograph
MedlinePlusa605021
Routes of
administration
Oral
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability60%
Protein binding1–2%
MetabolismHydrolysed to ganciclovir
Elimination half-life4 hours
ExcretionRenal
Identifiers
  • 2-[(2-amino-6-oxo-6,9-dihydro-3H-purin-9-yl)methoxy]-3-hydroxypropyl-(2S)-2-amino-3-methylbutanoate
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
ChEMBL
NIAID ChemDB
CompTox Dashboard (EPA)
Chemical and physical data
FormulaC14H22N6O5
Molar mass354.362 g/mol g·mol−1
3D model (JSmol)
  • O=C(OCC(OCn1c2N\C(=N/C(=O)c2nc1)N)CO)[C@@H](N)C(C)C
  • InChI=1S/C14H22N6O5/c1-7(2)9(15)13(23)24-4-8(3-21)25-6-20-5-17-10-11(20)18-14(16)19-12(10)22/h5,7-9,21H,3-4,6,15H2,1-2H3,(H3,16,18,19,22)/t8?,9-/m0/s1 checkY
  • Key:WPVFJKSGQUFQAP-GKAPJAKFSA-N checkY
 ☒NcheckY (what is this?)  (verify)

Valganciclovir (Valcyte, manufactured by Hoffmann–La Roche, and also known as Cymeval, Valcyt, Valixa, Darilin, Rovalcyte, Patheon, and Syntex[1]) is an antiviral medication used to treat cytomegalovirus infections. As the L-valyl ester of ganciclovir, it is actually a prodrug for ganciclovir.[2] After oral administration, it is rapidly converted to ganciclovir by intestinal and hepatic esterases.

Administration

Orally, available in 450 mg tablets. For patients who have received a transplant, the recommended dose is 900 mg once daily, starting within 10 days of transplantation and continuing for 6 months post transplantation. HIV patients might initially need to take the dose 900 mg twice daily for the first 3 weeks.[3]

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.
  4. The mechanism of this drug is activation via a viral protein kinase HCMV UL97 and subsequent phosphorylation by cellular kinases. The phosphotransferase enzyme can likewise activate valganciclovir.

Side effects

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, a follow-up double-blind, controlled study of 30 patients was completed, and although data has not yet been released, according to the Virus Induced CNS Dysfunction Association, “the data Dr. Montoya presented at the 2008 International Conference on HHV-6&7 indicated that patients on Valcyte experienced significant cognitive improvement.”, especially for those with elevated antibody levels to HHV-6 and EBV (VCA and EA). A recent study by Montoya and Kogelnik has shown somewhat disappointing results however.[4][5]

Price and patent status

Roche's Valcyte is protected by patent. However a generic version manufactured by Japanese-owned Indian company Daiichi-Ranbaxy was found by the District Court of New Jersey, USA not to infringe Roche's patent.[6]

The price of a four-month course of valganciclovir from Roche is about US$8,500 in high-income countries, $6,000 in India. However, the valganciclovir patent was rejected by the Indian Patent Office[7] in 2010, although Roche may appeal the rejection.

References

  • 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.
  • 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.
  • Pescovitz MD et al. Valganciclovir results in improved oral absorption of ganciclovir in liver transplant recipients. Antimicrob Agents Chemother. 2000;44(10):2811-5.
  • Reusser P. Antiviral therapy: current options and challenges. Schweiz Med Wochenschr. 2000;130(4):101-12.