Anti-Viral Agents Flashcards
What are the target stages of a virus life cycle?
absorption, penetration, uncoating, genome replication, RNA synthesis, protein synthesis, assembly, and release
HSV causes encephalitis in what region of the newborn brain?
temporal region
Acyclovir: Mechanism of action
analogue of deoxyguanosine, this pro-drug is activated by HSV viral TK, resulting in toxicity to HSV/VZV-infected cells only. Its active form inserts into DNA during synthesis, terminating the chain bc it lacks a 3’ hydroxyl group
Valacyclovir
oral herpes drug used for treatment or prophylaxis
Ganciclovir: Mechanism of action
inhibits CMV replication, phophorylated by a CMV kinase (but less specific and causes more toxicity to bone marrow)
Acyclovir resistance
mutations in viral TK or viral polymerase (usually only in immunocompromised)
Foscarnet, Cidofovir
DNA polymerase inhibitors, IV only, broad activity against many viruses, causes nephrotoxicity
Amantadine & Rimantadine
tricyclic amines that inhibit M2 protein of Influenza A (viral uncoating)
Oseltamivir & Zanamivir
NA inhibitors (prevent release); Zanamavir can cause bronchospasm
Downsides of NA inhibitors
lots of resistance, shortens length of flu by about 1 day, but only if prescribed early in course
What are adverse effects of influenza drugs?
M2 inhibitors cause CNS effects, oseltamivir causes GI symptoms, zanamivir causes bronchospasm
Hepatitis B is treated with what two broad classes of therapy?
DNA polymerase inhibitors and immunomodulators
Name 3 DNA polymerase inhibitors used for Hep B
tenofovir, adefovir, lamivudine
What immune modulator is used to treat HBV?
interferon
What 3 drugs are used together to treat HCV?
telaprevir (or boceprevir), ribavirin, and peg-interferon
