Foscarnet

From IDWiki

Background

Spectrum of Activity

Mechanism of Action

  • Acts as a pyrophosphate analogue that competitively and reversibly inhibits herpesvirus DNA polymerase, causing premature chain termination of DNA

Pharmacokinetics and Pharmacodynamics

  • CSF penetration 66% of serum levels

Dosing

Adult Dosing

  • CMV esophagitis and CMV colitis: 60 mg/kg/dose every 8 hours or 90 mg/kg/dose every 12 hours
  • CMV retinitis: induction with 60 mg/kg/dose every 8 hours or 90 mg/kg/dose every 12 hours, for 14 to 21 days, followed by maintenance with 90 to 120 mg/kg/dose once daily for 3 to 6 months or longer
  • Acyclovir-resistant mucocutaneous herpes simplex: 40 mg/kg/dose every 8 to 12 hours

Pediatric Dosing

  • Induction: foscarnet 60 mg/kg IV q8h or 90 mg/kg IV q12h
  • Maintenance: foscarnet 90 to 120 mg/kg IV q24h

Administration

  • Infusion rate not to exceed 1 mg/kg/min, with adult doses of 60 mg/kg typically infused over 1 hour, and doses of 90 to 120 mg/kg infused over 2 hours

Safety

Adverse Events

Monitoring

  • Close monitoring of electrolytes and creatinine is required

References

  1. ^  Dushyantha T. Jayaweera. Minimising the Dosage-Limiting Toxicities of Foscarnet Induction Therapy. Drug Safety. 1997;16(4):258-266. doi:10.2165/00002018-199716040-00003.