10.1 Antivirals Flashcards
Which classes of antivirals are used for hepatic infections? (3)
1) Interferons
2) Nucleotide/Nucleoside analogs
3) Protease Inhibitors
What is the DOC for HSV encephalitis?
Acyclovir
What are the 3 steps required for activation of acyclovir?
- Monophosphorylated by herpes virus-encoded enzyme (thymidine kinase)
- Host cell enzymes complete phosphorylation to di- and triphosphate forms
- Competes with dGTP; once incorporated into DNA causes chain termination & inhibition of viral DNA polymerase
How does Acyclovir resistance occur?
• Altered or deficient thymidine kinases
• Altered viral DNA polymerase with decreased affinity for
acyclovir
What is significant about valacyclovir?
Greater oral bio availability
Ganciclovir is the DOC for what?
CMV retinitis & CMV prophylaxis in
immunocompromised
What is the MOA of Ganciclovir?
- Phosphorylated by viral (UL97) and cell kinases
* DNA chain terminator & DNA polymerase inhibitor
What are the adverse effects of Gangiclovir?
- Myelosuppression
* Severe dose-dependent neutropenia
Cidofovir is used for what?
-Major use is treatment of CMV-induced retinitis in
HIV/AIDS
-Effective against HSV & ganciclovir resistant HSV
Which purine &pyrimidine analog must be phosphorylated by viral kinases?
Gangiclovir
Which purine and pyrimidine analog must be activated by host cell kinase instead of viral kinase?
Cidofovir
What is Trifluridine the DOC for?
• Drug of choice for HSV keratoconjunctivitis and
recurrent epithelial keratitis
Which drug is used for the topical treatment of HSV (cold sores)
Penciclovir
What is Foscarnet used for?
• Used for CMV retinitis in immunocompromised
patients, acyclovir-resistant HSV & CMV retinitis &
ganciclovir-resistant CMV & VZV
