Novel HIV Suppressive Approaches with Integrase Inhibitors
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Transcript of Novel HIV Suppressive Approaches with Integrase Inhibitors
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Novel HIV Suppressive Novel HIV Suppressive Approaches with Integrase Approaches with Integrase
InhibitorsInhibitors
Mark A WainbergMark A WainbergMcGill University AIDS CentreMcGill University AIDS Centre
Montreal, CanadaMontreal, Canada
Global distribution of HIV-1 subtypes
1.3 million1.3 million
4.8 million4.8 million
2 million2 million
B 10%B 10%A 12
%
A 12
%
URF 4.2%URF 4.2%
AG 6.7%
AG 6.7%
AE 3.1%AE 3.1%
G 5%G 5%
DD 3.6%3.6%
Rapid Selection of K65R Resistance in Subtype C Isolates
66
77
Previous work in our lab Previous work in our lab showed that MK-2048, a showed that MK-2048, a
Merck INSTI, selected G118R Merck INSTI, selected G118R followed by E138K. The latter followed by E138K. The latter
augmented levels of augmented levels of resistance against MK-2048 resistance against MK-2048 and also restored replicative and also restored replicative
fitness.fitness.
Major resistance pathways against INSTIs(clinical and tissue culture data)
Resistance pathwaysFold resistance
RAL EVG DTGY143 pathway
Y143C <10 <2 <2Y143R <50 <2 <2
T97A/Y143C >100 <2 <2T97A/Y143R >100 <2 <2
L74M/T97A/Y143G <50 ND <2L74M/T97A/E138A/Y143C <20 ND <2
N155 pathway N155H <50 <50 <2
E92Q/N155H <100 >100 <10L74M/N155H <50 <50 <2
Q148 pathway Q148H <20 <10 <2Q148K <100 <100 <2Q148R <50 <100 <2
E138K/Q148H <10 <20 <2E138K/Q148K >100 >100 <20E138K/Q148R >100 >100 <10G140S/Q148H >100 >100 <20G140S/Q148K <10 <100 <2G140S/Q148R >100 >100 <10
E138A/G140S/Y143H/Q148H >100 ND <50Quashie et al., Curr. Opin. Infect. Diseases, in press
Secondary INSTI-resistance mutations often restore HIV replication capacity
Mbisa et al., Infect. and drug resistance, 2011--Canducci et al., JAC, 2010--Reigadas et al., Plos One, 2010--Delelis et al., AAC, 2009
Secondary Mutations (pathway)
Effect on viral fitness in the presence of primary resistance mutations
Y143 pathway - (often)
L74M, T97A +
N155H pathway -
Q95K, T97Q, G163R/K
+
Q148 pathway -
G140A/S/C, E138K/A
+
Dolutegravir activity on RAL-resistant clinical isolates
(n=39)(median IC50 for wild-type=1.07 nM)
GenotypeMedian fold
change
N155H 1.37
Y143R/T97A 1.05
Q148H/G140S 3.75
Q148R/G140S 13.3
Underwood et al., JAIDS, 2012
Resistance to INSTIs in clinical trials
in treatment-naïve patients
Treatment
Major resistance mutations detected by genotyping in treatment-naïve patients failing therapy
Minor resistance mutations
RaltegravirY143
N155HQ148
Multiple
Elvitegravir
T66IE92Q
N155HQ148
Multiple
Dolutegravir
NONE NONERALTEGRAVIRCooper et al., NEJM, 2008Sichtig et al, JAC, 2009Canducci et al, AIDS, 2009Hatano et al, JAIDS, 2010
ELVITEGRAVIRSax et al, Lancet, 2012DeJesus et al, Lancet, 2012
DOLUTEGRAVIRvanLunzen et al., Lancet Infect. Dis., 2012
Selection results with DTG
Quashie, et al, Journal of Virology 2012
Selection results with DTG
Quashie, et al, Journal of Virology 2012
Selection results with DTG
Quashie, et al, Journal of Virology 2012
Subtype-specific mutations selected in vitro with
dolutegravir
HIV-1 subtype
Most common mutations selected with
dolutegravir
B R263K, H51Y
C G118R, H51Y
Quashie, Mesplède et al., Journal of Virology, 2012
The R263K mutation confers low-level resistance to
dolutegravir in cell culture
Genotype IC50 fold change*
R263K 2.5 to 6
*Methodological differences(EC50 for wild-type ≈1-6nM) Quashie, Mesplède et al., Journal of Virology, 2012
The R263K mutation decreases integrase activity in cell-free
assays
Quashie, Mesplède et al., Journal of Virology, 2012
The R263K mutation decreases dolutegravir residency time
in an integrase-vDNA complex
The addition of H51Y to R263K further decreases IN strand
transfer activity
A B
The combination of H51Y and R263K negatively impacts viral
fitness
Effects of G118R and H51Y on in vitro strand transfer activity
IN protein
Relative strand transfer activity
(RFU/hr)Vmax ± SEM
WT 7,751.2 480.7H51Y 7,590.0 265.3G118R 6,138.5 621.5H51Y/G118R 3,223.0 130.2
Effects of H51Y, G118R and R263K mutations
on susceptibility to dolutegravir in cell culture
Genotype IC50 fold change*
R263K 2.5 to 6
H51Y 1 (no change)
H51Y/R263K 6 to 12
G118R 3 to 7
H51Y/G118R 6 to 10
*Methodological differences(EC50 for wild-type ≈1-6nM)
Dolutegravir resistance associates with
a decrease in viral replication capacity
Genotype ResistanceEffect on
viral fitness
R263K + -
H51Y None None
H51Y/R263K ++ - -
G118R + -
H51Y/G118R ++ - -
Conclusions• Resistance mutations selected in vitro with
dolutegravir are: R263K or G118R plus H51Y
• R263K and G118R confer low-level resistance against dolutegravir, e.g. 2.5-6 fold
• The addition of H51Y to either R263K or G118R increases resistance against DTG but also further decreases viral fitness
• These findings help to explain why resistance against dolutegravir in INSTI-naïve patients has not been observed
No compensatory mutations in regard to DTG resistance and viral fitness have developed over more than one year in culture. Might there be other implications for a drug that selects for an unfit virus and can animal models be of use?
• Bluma Brenner• Hongtao Xu• Dimitri Coutsinos• Jerry Zaharatos• Maureen Oliveira• Thibault Mesplède• Peter Quashie
Acknowledgements
MERCI