Anti-Virals Flashcards
Mechanism of action of Ion Channel Blockers (Adamantane Drugs)
Block the viral M2 proton channel, prevent uncoating of influenza virus (early endosome)
<p>Names of Adamantane drugs </p>
<p>Rimantadine, Amantadine </p>
Enfuvirtide and Maraviroc act on what type of virus
HIV
Enfuvirtide MOA
Mimics HR2, binds to HR1 and prevents HR1-HR2 interaction, thus preventing fusion of HIV with CD4 T cell
Maraviroc MOA
small molecule antagonist that binds to CCR5. Only blocks strains of HIV that use CCR5 receptor (HIV-1)
Name the 2 antivirals that act as nucleic acid synthesis inhibitors
Acyclovir (valacyclovir), Ganciclovir (valganciclovir)
Acyclovir & Ganciclover act on what viruses
Herpes simples viruses 1 & 2, Varicella zoster virus, & cytomegalovirus
First step needed prior to acyclovir & ganciclover activity
Require metabolic activation to a triphosphate form
MOA of Acyclovir & ganciclover
After being metabolically activated to a triphosphate form, acyclovir or ganciclover compete with dGTP for terminal end of growing DNA chain within viral DNA polymerase. After binding to terminal end, traps the polymerase at that location, preventing further chain elongation.
Does acyclovir/ganciclover use host or viral kinase for activation?
Viral kinase used for addition of first phosphate group
Route of administration for acyclovir/ganciclover?
As a orally absorbed pro drug (valacyclovir/valganciclover)
Name NRTI’s used to treat HIV
ABACAVIR LAMIVUDINE TENOFOVIR DISOPROXIL ZIDOVUDINE (AZT) EMTRICITABINE didanosine (ddl) stavudine
Metabolic activation of nucleoside reverse transcriptase inhibitors (NRTIs) occurs by host or viral kinase?
Host kinase used for addition of first phosphate group.
NRTI inhibition type (competitive or noncompetitive)?
NRTI’s competitively inhibit reverse transcriptase.
Indirect inhibition of polymerase by NRTI has what consequence?
NRTIs also inhibit host cell mitochondrial DNA polymerase, causing depletion of mitochondrial DNA and subsequently mitochondrial RNA and peptides involves in ox phos. This ultimately leads to mitochondrial dysfunction, and leads to several toxicities associated with NRTIs.
Name 2 NNRTIs
Efavirenz, Nevirapine
Where do NNRTIs (efavirenz & nevirapine) bind
the hydrophobic pocket in the p66 subunit of HIV-1 reverse transcriptase
What does Raltegravir inhibit
the catalytic activity of HIV-1,2 encoded integrase –> viral DNA cannot be incorporated into host DNA
What are the HIV-1 Protease Inhibitiors?
Atazanavir, Ritonavir, amprenavir, indinavir, lopinavir, nelfinavir, saquinavir
How do HIV-1 Protease Inhibitors work?
They inhibit aspartyl protease enzymes that cleave HIV gag and pol precursor polypeptides that are required for HIV virion maturation
Which HIV-1 Protease inhibits CYP activity?
Ritonavir inhibits CYP3A4
What drugs are used to treat Hepatitis C??
Boceprevir, Telaprevir
Efavirenz and Nevirapine work on what type of virus?
HIV-1 only, not HIV-2
Raltegravir acts on what type of virus?
HIV-1, HIV-2 –> HIV integrase inhibitor
