W06_04Antiviral Therapy Flashcards
why do antivirals have a low therapeutic ratio?
many inhibit nucleic acid synthesis.
what is clinical latency (viruses)
ability of the virus to lay dormant in the body
MoA for acyclovir?
nucleoside analogue
MoA for valacyclovir?
prodrug for acyclovir (nucleoside analogue)
MoA for famciclovir?
prodrug for acyclovir (nucleoside analogue)
MoA for ganciclovir?
nucleoside analogue
MoA for valganciclovir?
prodrug for ganciclovir (nucleoside analogue)
what are the mechanisms of resistance of nucleoside analogues?
thymidine kinase incompatibilities, can’t phosphorylate, DNA polymerase incompatibilities
treatment for herpes simplex encephalitis?
IV acyclovir for 14-21 days
note VZV requires higher drug concentrations to inhibit the replication.
note: use valacyclovir or famciclovir, rather than acyclovir. use acyclovir in immunocompromised hosts
treatment for CMV retinitis?
iv ganciclovir or PO valganciclovir
what is hemoglutinin?
a ligand on virions
what activates ion channels in the lysosomes when a virus is ingested?
M2 protein. ions dissolve the envelope
neuraminidase is an enzyme that does what?
chops the hemoglutinin/hemoglutinin receptor bonds between virions and declumps them
what do adamantanes do?
inhibit the M2 protein that prevents envelope digestion/uncoating
