Comparative Pharmacology
Head-to-head clinical analysis: ACYCLOVIR SODIUM versus LETERMOVIR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ACYCLOVIR SODIUM versus LETERMOVIR.
ACYCLOVIR SODIUM vs LETERMOVIR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Acyclovir is a synthetic nucleoside analogue with activity against herpes simplex virus (HSV) types 1 and 2, and varicella-zoster virus (VZV). It is converted to acyclovir monophosphate by viral thymidine kinase, then further phosphorylated to acyclovir triphosphate, which competitively inhibits viral DNA polymerase and incorporates into viral DNA, causing chain termination.
Letermovir is an antiviral agent that inhibits the human cytomegalovirus (CMV) terminase complex, specifically the pUL56 subunit, thereby preventing viral DNA processing and packaging.
Dosing is indication-specific. For herpes simplex encephalitis: 10 mg/kg IV every 8 hours for 10–14 days (adults and children ≥12 years) or 20 mg/kg IV every 8 hours (3 months–12 years). For severe genital herpes: 5 mg/kg IV every 8 hours for 5 days. For mucocutaneous HSV in immunocompromised: 5 mg/kg IV every 8 hours for 7–14 days. For varicella zoster in immunocompromised: 10 mg/kg IV every 8 hours for 7 days. For neonatal HSV: 20 mg/kg IV every 8 hours for 14–21 days (disseminated/CNS) or 14 days (skin/eyes/mouth).
480 mg orally once daily (two 240 mg tablets).
None Documented
Clinical Note
moderateLetermovir + Teriflunomide
"The serum concentration of Teriflunomide can be increased when it is combined with Letermovir."
Clinical Note
moderateLetermovir + Haloperidol
"The metabolism of Haloperidol can be decreased when combined with Letermovir."
Clinical Note
moderateLetermovir + Clotrimazole
"The metabolism of Clotrimazole can be decreased when combined with Letermovir."
Clinical Note
moderateLetermovir + Dronedarone
None Documented
Terminal elimination half-life: 2.5-3.3 hours in adults with normal renal function; up to 20 hours in anuria/end-stage renal disease.
The terminal elimination half-life is approximately 12 hours (range 10–18 hours) in healthy subjects, allowing once-daily dosing.
Primarily renal excretion via glomerular filtration and tubular secretion: 62-91% of dose excreted unchanged in urine within 24 hours; minor biliary/fecal elimination (<2%).
Letermovir is primarily eliminated via biliary/fecal excretion (approximately 93% of the dose recovered in feces, with <2% as unchanged drug) and renal excretion accounts for <7% (mostly as metabolites, <1% unchanged).
Category A/B
Category C
Antiviral
Antiviral
"The metabolism of Dronedarone can be decreased when combined with Letermovir."