Comparative Pharmacology
Head-to-head clinical analysis: FOSCAVIR versus HEPSERA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FOSCAVIR versus HEPSERA.
FOSCAVIR vs HEPSERA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Foscarnet is a pyrophosphate analog that selectively inhibits viral DNA polymerase and reverse transcriptase by binding to the pyrophosphate binding site, preventing the cleavage of pyrophosphate from deoxynucleotide triphosphates, thereby inhibiting viral DNA synthesis. It does not require activation by viral thymidine kinase, making it active against acyclovir-resistant HSV and VZV, and ganciclovir-resistant CMV.
Acyclic nucleotide analog of adenosine monophosphate; inhibits hepatitis B virus (HBV) DNA polymerase by competing with the natural substrate dATP, causing DNA chain termination after incorporation into viral DNA.
Induction: 60 mg/kg IV every 8 hours for 2-3 weeks, then maintenance: 90-120 mg/kg IV once daily. Administer as a 2-hour infusion via central line.
10 mg orally once daily.
None Documented
None Documented
Terminal elimination half-life is approximately 3-5 hours in patients with normal renal function; can extend to 48-120 hours in severe renal impairment (CrCl <20 mL/min), requiring dose adjustment and therapeutic drug monitoring.
Terminal elimination half-life is approximately 6-9 hours in patients with normal renal function. In renal impairment, half-life is prolonged (up to 18 hours in moderate impairment, >30 hours in severe impairment). Steady-state is achieved within 5-7 days.
Primarily renal excretion (>80% as unchanged drug) via glomerular filtration and tubular secretion; minimal biliary/fecal elimination (<5%).
Primarily renal; 70-90% of an oral dose is excreted unchanged in urine via active tubular secretion and glomerular filtration. Biliary/fecal elimination accounts for <5%.
Category C
Category C
Antiviral
Antiviral