HIV Flashcards
explain the HIV lifecycle
- HIV attaches to CD4 cell
- HIV enters CD4 cell
- capsid enters the nucleus where HIV proteins/enzymes are released
- reverse transcriptase makes a double stranded HIV DNA
- integrase enables HIV DNA to join host cell DNA
- protease cuts and assembles new HIV
- each cell makes hundred of new HIV virons
- CD4 cell will then die
how do HIV cells bind to CD4 cells?
gp120 and gp41 receptor protein on the HIV cell binds to CD4 receptor and CCR5 co-receptors on the CD4 cell
what are some HIV cell cycle drug targeting?
- NRTIS/NNRTIS
- attachment/entry inhibitors
-monoclonal antibodies
-attachment inhibitors
-CCRS inhibitors - capsid inhibitors - intracellular and extracellular
- integrase inhibitors -INIs
- protease inhibitors
- maturation inhibitors
why is drug importance important?
- lifelong treatment needed
- resistance = limited future options
- population of people w resistance
- greater cost
when does drug resistance occur?
found before starting treatment - at the time of infection
found during treatment during treatment interruptions -acquired
how does drug resistance occur
random mutations during reverse transcriptase after changing environmental pressures
what can change in environmental pressure
drug concentration
how is drug resistance tested?
viral load needs to be >400 copies/mL
therefore blood supply must be amplified before testing
takes three weeks for results - give high barrier drugs
what would you give when undergoing drug resistance tests?
high barrier drugs
what are low barrier drugs?
single mutations = high level resistance
do not use in mono therapy
do not use in a regimen if they do not fully suppress viral therapy
what are examples of low barrier drugs?
zidovudine
lamivudine
rilprivirine
what are examples of high barrier drugs?
darunavir with ritonavir,
dolutegravir
bictegravir
what are high barrier drugs?
develop resistance slowly even in mono therapy
single mutations = low level resistance
more forgiving drugs during non-adherence periods
