Antivirals - HIV Flashcards
HIV attacks which human cells?
CD4, macrophages, microglial
goal of antiviral HIV therapy
reduce viral load
which 2 classes of HIV antivirals BLOCK VIRAL ENTRY INTO CELLS
- CCR5 antagonists
2. fusion inhibitors
which 3 classes of HIV antivirals INHIBIT ENZYMES REQUIRED FOR HIV REPLICATION
- reverse transcriptase inhibitors
- integrase inhibitors
- protease inhibitors
what are the 2 subclasses of reverse transcriptase inhibitors?
nucleoside + non-nucleoside
what is the receptor on CD4 cells that HIV virus likes to bind with for entry into cell?
CCR5
mechanism of action for CCR5 antagonists?
blocks CCR5 receptor from binding with gp 120 on HIV virion
which receptor on the CD4 cell is present much more often at the START of infection?
CCR5
main thing to know / test for before administering CCR5 antagonists for HIV treatment?
test client to determine if their HIV strain is CCR5 tropic
using this receptor ro gain entry into CD4 cell
what is the prototype for CCR5 antagonists?
maraviroc (SelzENTRY)
AE/risk of maraviroc
hepatotoxicity risk
mechanism of action for fusion inhibitors
blocks fusion of HIV cells with CD4 cell (drug binds to gp41 on HIV cell to prevent fusion)
prototype of fusion inhibitor
enFUvirtide (FUZEon)
when are fusion inhibitors used?
when there is resistance to other HIV antivirals
2 downsides to fusion inhibitors (r/t patient access)
- costly!!
- Subcut injections BID
=not an easy drug
most common AE of enFUvirtide (FUZEon) + how to avoid
injection site rxns (98%)
erythema, tenderness, pain, ecchymosis
prevention: rotate sites + avoid deep injections
mechanism of action for: nucleotide/nucleoside reverse transcriptase inhibitors (NRTI) aka NUKES
subs a dummy base pair –> inhibits creation of viral DNA
what class of drug is used mostly for initial regimen?
nukes (NRTIs)
what are the 2 prototype for NRTI/nukes
- zidovudine (AZT)
2. abacavir (Ziagen, ABC)
side effects of AZT (long term use)
anemia + neutropenia (affects bone marrow) = low H+H/low WBCs
re: pharmacogenomics, what do we need to look for with abacavir? if they have this, what are they at risk for if they take the drug?
test for genetic variant HLA-B*5701 –> @ risk for severe hypersensitivity rxn (anaphylaxis)
what is the mechanism of action for non-nukes/non-nucleotide reverse transcriptase inhibitors (NNRTIs)
a cog in a wheel - binds to center of enzyme and causes direct inhibition –> STOPS it!
AE of non-nukes
rash
hypersensitivity rxns
–> SJS (STOP if they have a severe rxn!!!)
a lot of drug-drug interactions
what is the prototype for non-nukes
efaVIRenz (Sustiva)
reVERse Nukes = VIR enZ