Comparative Pharmacology
Head-to-head clinical analysis: TYZEKA versus VALGANCICLOVIR HYDROCHLORIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: TYZEKA versus VALGANCICLOVIR HYDROCHLORIDE.
TYZEKA vs VALGANCICLOVIR HYDROCHLORIDE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Telbivudine is a synthetic thymidine nucleoside analogue with activity against hepatitis B virus (HBV). It is phosphorylated intracellularly to the active triphosphate form, which competes with natural thymidine triphosphate for incorporation into viral DNA, causing chain termination and inhibition of HBV DNA polymerase (reverse transcriptase).
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.
600 mg orally once 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 elimination half-life is approximately 15 hours (range 12-20 hours) in patients with normal renal function; half-life is prolonged in renal impairment, requiring dose adjustment.
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).
Renal excretion of unchanged drug accounts for approximately 40% of the administered dose; biliary/fecal excretion accounts for approximately 60%.
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, Hepatitis B
Antiviral