What Is Valganciclovir?

Valganciclovir is a synthetic 2-deoxyguanosine analogue, and is a prodrug of the antiviral drug ganciclovir, which can greatly reduce the toxicity of ganciclovir. It has the same pharmacodynamic characteristics as ganciclovir.

Chinese name: Valganciclovir

Foreign name: Valganciclovir
Drug classification: Antivirals

Valganciclovir Basic Information

Valganciclovir details

Chinese name: Valganciclovir

Chinese alias: (S) -2-amino-3-methylbutanoic acid (R, S) -2-[(2-amino-6-oxo-1,6-dihydro-9H-purine-9-yl ) Methoxy] -3-hydroxypropyl ester

English name: Valganciclovir

English alias: valgancyclovir

CAS number: 175865-60-8

Molecular formula: C ₁₄ H ₂₂ N ₆ O ₅

Molecular weight: 354.36200

Exact mass: 354.16500

PSA: 171.37000

Valganciclovir physicochemical properties

Density: 1.59g / cm ³

Boiling point: 629.1ºC at 760mmHg

Flash point: 334.3ºC

Vapor pressure: 1.08E-16mmHg at 25 ^[1]

Valganciclovir Valganciclovir Related Drug Sheet Information

Valganciclovir pharmacological effects

This product is a synthetic 2-deoxyguanosine analog, which is a prodrug of the antiviral drug ganciclovir, which can greatly reduce the toxicity of ganciclovir. It has the same pharmacodynamic characteristics as ganciclovir. After oral administration of valganciclovir, it is rapidly hydrolyzed into ganciclovir under the action of intestinal mucosal cell esterase and liver esterase, and ganciclovir generates ganciclovir triphosphate under the virus and intracellular enzyme phosphorylation The latter competes with deoxyguanosine triphosphate (dGTP) as a substrate for viral DNA polymerase, thus inhibiting the synthesis of viral DNA, thereby generating anti-cytomegalovirus (CMV) activity. In vitro, ganciclovir has a 26-fold stronger effect on CMV than acyclovir. In vitro and in vivo studies have shown that ganciclovir is able to suppress the immune response caused by CMV and transplant rejection, and is also effective in animal models of severe CMV infection. The ganciclovir-resistant germline was isolated from a small number of patients with CMV infection, and they had point mutations in genes encoding the protein kinase and viral DNA polymerase that phosphorylated ganciclovir.

medicine interactions

1. Zidovudine, ergophenolate or azathioprine in combination with this product can reduce neutrophils and increase adverse reactions such as anemia. 2. Nephrotoxic drugs damage kidney function, slow the elimination of ganciclovir in vivo, drug accumulation, and increase toxicity. 3 Probenecid and other renal excretion drugs can reduce the clearance of ganciclovir and cause its toxicity to increase. 4 Combination with other cytotoxic drugs increases the risk of bone marrow suppression, gastrointestinal and skin adverse reactions, so it cannot be combined. 5. The metabolite of valganciclovir, ganciclovir, can significantly increase the bioavailability of didanosine, and the latter should be closely monitored for toxicity. 6. Combination with imipenem / cilastatin increases the likelihood of epilepsy

Pharmacokinetics

Studies show that the bioavailability of this product for oral absorption is 60%, which is 10 times that of ganciclovir, and it is quickly absorbed and hydrolyzed to ganciclovir. For patients with advanced CMV and HIV infections and patients receiving liver transplantation, the systemic valganciclovir concentration is very small because the area under the curve (AUC) of valganciclovir at 24 hours is only 1 % To 2%. In patients with advanced CMV and advanced HIV and liver transplantation, the effect of oral valganciclovir 900 mg once daily is equivalent to an intravenous injection of 5 mg / kg ganciclovir. Compared with fasting, taking valganciclovir with food can increase the concentration of ganciclovir. Valganciclovir is eliminated by glomerular filtration and tubular secretion. The single-dose valganciclovir 360 mg and the single-dose intravenous ganciclovir 5 mg / kg had similar elimination half-lives (t1 / 2) at the endpoint. In liver transplant recipients, the renal clearance of ganciclovir is given by a single oral dose of valganciclovir 450 mg or 900 mg and by a single oral dose of ganciclovir 1000 mg within 18 h and by intravenous ganciclovir 5 mg The results obtained at / kg are similar.

Dosage form and specifications

Tablet: 450mg.

Valganciclovir indications

For cytomegalovirus (CMV) retinitis in patients with acquired immunodeficiency syndrome (AIDS).

Valganciclovir contraindications

1. This product is contraindicated in those allergic to ganciclovir or valganciclovir. 2. Neutrophils <0.5 × 109 / L, platelets <25 × 109 / L, and hemoglobin concentration <80g / L are contraindicated. 3 This product is contraindicated in hemodialysis patients. 4 The safety and efficacy of this product for children have not been determined, so it is not recommended for children.

Valganciclovir notes

1. Patients with renal insufficiency should use this product with caution and adjust the dosage appropriately. Use with caution in pregnant women. Patients with preexisting myelosuppression, receiving myelosuppressive drugs or radiotherapy, and those with a history of hemocytopenia or a response to hemocytopenia should use with caution. 2. Due to the different bioavailability of this product and ganciclovir, the medication cannot be replaced one-on-one. 3 Because the mutagenic effects of ganciclovir can seriously affect spermatogenesis and fertility, users should take contraceptives during treatment and at least 90 days after treatment. 4 Overdose may cause increased renal toxicity, and hemodialysis and increased electrolytes may help lower plasma drug concentrations. 5. Store at 15 30 .

Valganciclovir adverse reactions

1. Gastrointestinal reactions: diarrhea, nausea, vomiting, and abdominal pain. 2. Hematological reactions: neutropenia and anemia, thrombocytopenia, bone marrow suppression. 3 Central nervous system reactions: fever, headache, insomnia, peripheral nervous disorders, paresthesia, epilepsy, psychosis, hallucinations. 4 Eye reaction: retinal detachment. 5. Other adverse reactions: renal failure, other local or systemic reactions. Ganciclovir is carcinogenic and teratogenic in animal tests and causes azoospermia.