HIV Resistance Primer Flashcards
M184V (or I) confers COMPLETE resistance to:
lamivudine (3TC) and
emtricitabine (FTC).
These drugs have a low barrier to resistance.
M184V (or I) enhances the virologic activity to:
zidovudine (ZDV/AZT) and tenofovir (TDF)
K65R is selected by ______ and confers resistance to ALL ____ except ______ .
. .
tenofovir (TDF/TAF) - intermediate resistance
ALL NRTI
except zidovudine (ZDV/AZT )
K103N is the signature mutation for:
efavirenz (EFV).
Y181C is the signature mutation for:
nevirapine (NVP).
efavirenz and nevirapine, have a low genetic barrier
and are COMPLETELY cross-resistant to one another.
E138K is the signature mutation for:
rilpivirine (RPV) and etravirine (ETR).
E 138 r
E138K, K101E, and/or Y181C
Rilpivirine or etravirine and consequently,
resistance to ALL NNRTIs.
I50L confers resistance to:
atazanavir (ATV)
“driving your ATV on I-50”
Q148 mutation decreases activity of:
Dolutegravir (DTG) and bictegravir (BIC)
iiQ148
The MoCo mech of virologic failure for Maraviroc is:
Selection of pre-existing X4 virus (X4
or D/M on tropism test).
Acyclovir - Resistance
– Acyclovir resistance also confers resistance to valacyclovir, famciclovir
– Mechanisms of resistance
- Thymidine kinase deficient viral mutants (absent TK) – remain sensitive to foscarnet, cidofovir
- Thymidine kinase alterations – Same as above
- UL 54 mutation – Acyclovir resistant: may also be resistant to ganciclovir or foscarent or cidofovir
Ganciclovir and Valganciclovir
• Resistance usually due to drug pressure
• Requires initial phosphorylation by CMV UL97 ser/thr kinase
– UL 97-only resistant to ganciclovir
– UL 54- resistant to ganciclovir and often to foscarnet and /or cidofovir
Q151M mutation high level resistance to ____ but ___ retains sensitivity .
Lamivudine (3TC)
Tenofovir (TDF)
