Comparative Pharmacology
Head-to-head clinical analysis: SYMMETREL versus VALGANCICLOVIR HYDROCHLORIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SYMMETREL versus VALGANCICLOVIR HYDROCHLORIDE.
SYMMETREL vs VALGANCICLOVIR HYDROCHLORIDE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Inhibits influenza A virus uncoating and viral RNA replication; increases dopamine release and blocks dopamine reuptake in the CNS.
Valganciclovir is an L-valyl ester prodrug of ganciclovir. After oral administration, it is rapidly hydrolyzed to ganciclovir, which is a synthetic guanosine analog. Ganciclovir is phosphorylated to ganciclovir triphosphate, which competitively inhibits viral DNA polymerase and incorporates into viral DNA, causing termination of viral DNA elongation.
100 mg orally twice daily; may increase to 200 mg orally twice daily if tolerated, usually in divided doses. For Parkinson's disease, 100 mg orally twice daily; for drug-induced extrapyramidal reactions, 100 mg orally twice daily.
Oral: 900 mg twice daily for cytomegalovirus (CMV) retinitis induction in immunocompromised patients; for prevention in transplant recipients: 900 mg once daily starting within 10 days of transplant.
None Documented
None Documented
Terminal half-life: 24-48 hours (young adults); 48-72 hours (elderly); may extend to 7-10 days in severe renal impairment. Clinically, steady-state achieved in 4-7 days.
Terminal elimination half-life of ganciclovir after valganciclovir administration is approximately 4-5 hours in patients with normal renal function. In renal impairment, half-life is significantly prolonged, up to 30-40 hours in severe impairment (CrCl <10 mL/min).
Primarily renal excretion (90-95% unchanged) via glomerular filtration and tubular secretion; minor fecal (<5%). Dose adjustment required in renal impairment.
Primarily renal excretion of unchanged drug (approximately 90%), with the remainder as ganciclovir. Biliary/fecal elimination accounts for <5%.
Category C
Category D/X
Antiviral and Antiparkinsonian
Antiviral