Comparative Pharmacology
Head-to-head clinical analysis: HARVONI versus TYZEKA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HARVONI versus TYZEKA.
HARVONI vs TYZEKA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fixed-dose combination of ledipasvir, an HCV NS5A inhibitor, and sofosbuvir, an HCV NS5B nucleotide polymerase inhibitor. Ledipasvir inhibits HCV NS5A protein essential for viral replication and assembly; sofosbuvir is a prodrug that after intracellular metabolism acts as a chain terminator by inhibiting NS5B RNA-dependent RNA polymerase.
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).
One tablet (90 mg ledipasvir/400 mg sofosbuvir) orally once daily with or without food for 12 weeks. For treatment-naïve patients with genotype 1 and cirrhosis, 24 weeks may be considered. For genotype 4, 12 weeks recommended.
600 mg orally once daily
None Documented
None Documented
Ledipasvir: 47 hours; Sofosbuvir: 0.5 hours; GS-331007 (predominant circulating metabolite): 27 hours; clinical context: supports once-daily dosing with no accumulation beyond steady state by day 7
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.
Ledipasvir: 86% fecal, 1% renal; Sofosbuvir: 80% renal (as inactive metabolite GS-331007), 14% fecal; GS-331007: 78% renal
Renal excretion of unchanged drug accounts for approximately 40% of the administered dose; biliary/fecal excretion accounts for approximately 60%.
Category C
Category C
Antiviral
Antiviral, Hepatitis B