Detailed instructions for valganciclovir/vansevir: indications and medication precautions

1. Overview

Generic Name: Valganciclovir, Valganciclovir

Product name: VANCYTE, VALCYTE

2. Indications

Valganciclovir is mainly used to treat cytomegalovirus (CMV) retinitis in patients with acquired immunodeficiency syndrome (AIDS), and is also used to prevent CMV disease in high-risk groups. These high-risk patients include patients receiving kidney, heart, and kidney-pancreas transplants, especially cases in which the donor is CMV-seropositive and the recipient is CMV-seronegative (D+/R-). For pediatric patients, valganciclovir is suitable for the prevention of CMV disease in high-risk kidney transplant and heart transplant patients aged 4 months to 16 years.

3. Usage and dosage

For adult patients, the recommended dose of valganciclovir tablets is900 mg (two 450 mg tablets), taken orally twice daily for 21 days for the induction treatment of cytomegalovirus retinitis. After the induction course, the dose can be adjusted to 900 mg once daily. The recommended dose for the prevention of CMV disease in adult patients who have received a heart or kidney-pancreas transplant is 900 mg once daily, starting 10 days after transplantation and continuing for 100 to 200 days, depending on the type of transplant.

Dosage for pediatric patients should be determined by calculating creatinine clearance (CrCl) based on the modifiedSchwartz formula, combined with bovine serum albumin (BSA). The calculated dose should not exceed 900mg/day. For pediatric heart transplant patients 1 month to 16 years of age and pediatric kidney transplant patients 4 months to 16 years of age, the recommended daily dosage should be initiated within 10 days after transplantation and continued as needed for 100 to 200 days after transplantation.

For adult patients with renal impairment, the specific dosage should be adjusted based on creatinine clearance. For cases undergoing hemodialysis, dosage recommendations are unclear; for patients with CrCl between 10 and 24 mL/min, 450 mg should be given every 2 days and a regimen of 450 mg twice a week should be maintained.

4. Adverse reactions

The side effects of valganciclovir are similar to those of ganciclovir. Common adverse reactions include diarrhea, fever, fatigue, nausea, tremor, and hematological abnormalities such as neutropenia, anemia, and leukopenia. Similar adverse reactions have been reported in children receiving valganciclovir.

5. Storage

Valganciclovir tablets are usually available as 450 mg pink oval biconvex film-coated tablets and should be stored at 20 to 25°C (68 to 77°F). Its oral solution is a white to slightly yellow powder. The prepared solution should be refrigerated at 2°C to 8°C (36°F to 46°F) and should not exceed 49 days. Do not freeze.

6. Taboo

This drug is contraindicated in patients with significant allergic reactions to valganciclovir and its components.

7. Mechanism of action

Valganciclovir is the prodrug of ganciclovir, and its antiviral effect is mainly directed against CMV. After oral administration, valganciclovir is rapidly converted into ganciclovir, which is phosphorylated into the active form by viral protein kinase pUL97 and inhibits viral DNA polymerase pUL54, thereby effectively inhibiting the replication and spread of CMV.

Reference materials:https://go.drugbank.com/drugs/DB01610