Pawlotsky resistance

Hépatite C: Résistanceaux Traitements

Prof. Jean-Michel Pawlotsky

CNR des Hépatites B, C et deltaLaboratoire de Virologie & INSERM U635

Hôpital Henri MondorUniversité Paris XII

Créteil

HCV Resistance

• IFN--ribavirin treatment failure

• HCV resistance to DAAs

• Treatment Failure with the Triple Combination of Peg-IFNa, Ribavirin and Telaprevir or Boceprevir

• HCV Resistance in All-oral, IFN-free regimens

I

IFN--Ribavirine TreatmentFailure

Incidence of Peg-IFN-RibavirinTreatment Failures

2%

0

15

30

45

60 54%48%

58%

24%

16% 18%

Genotype 1 Genotypes 2/3

PEG-IFN-α2a+ribavirin (Fried et al)

PEG-IFN-α2a+ribavirin (Hadziyannis et al)

PEG-IFN-α2b+ribavirin (Manns et al)

(Manns et al, Lancet 2001 ; Fried et al, N Engl J Med 2002 ; Hadziyannis et al, Ann Intern Med 2004)

Viral FactorsDisease

Characteristics

HostFactors

TreatmentSchedule

TreatmentFailure

Viral FactorsDisease

Characteristics

HostFactors

TreatmentSchedule

TreatmentFailure

Viral Resistance

• Intrinsic properties of viral strains that counteract the antiviral action of antiviral drugs

Incidence of Peg-IFN-RibavirinTreatment Failures

2%

0

15

30

45

60 54%48%

58%

24%

16% 18%

Genotype 1 Genotypes 2/3

PEG-IFN-α2a+ribavirin (Fried et al)

PEG-IFN-α2a+ribavirin (Hadziyannis et al)

PEG-IFN-α2b+ribavirin (Manns et al)

(Manns et al, Lancet 2001 ; Fried et al, N Engl J Med 2002 ; Hadziyannis et al, Ann Intern Med 2004)

HCV Kinetics by GenotypeEC-sponsored DITTO-Trial

(Pawlotsky et al., manuscript in preparation)

0

1

2

3

4

5

6

7 HCV RNA (log IU/ml)

0 4 7 8 15 22 291-7-28

Genotype 4

Genotype 1

Genotype 3

* = significant difference, 4 and 1 vs 3

*

*

**

* **

Quantitative assay cutoff

Qualitative assay cutoff


0

1

2

3

4

5

6


0 4 7 8 15 22 291-7-28

Genotype 4

Genotype 1

Genotype 3


*

*

**

* **





0

1

2

3

4

5

6


0 4 7 8 15 22 291-7-28

Genotype 4

Genotype 1

Genotype 3


*

*

**

* **





0

1

2

3

4

5

6


0 4 7 8 15 22 291-7-28

Genotype 4

Genotype 1

Genotype 3


*

*

**

* **




Summary

• HCV resistance to IFN- antiviral effect exists

• Its molecular mechanisms are unknown and probably complex

• It accounts for only a small part of IFN--based treatment failures

Genome-Wide Association Studies (GWAS)

A population with distinct clinical

phenotypes

> 3 billion nucleotides> 10 million SNPs

GWAS chip> 500,000 ‘tag’ SNPs> 90% coverage ofcommon genetic

variation

SNP associationBioinformatics to process data and

associate genotype with

phenotype

http://www.sb.fsu.edu/~xray/Images/DellComputer.jpg














SNP and SVR in the IDEAL Trial

IL28B

(Ge et al, Nature, 2009;461:399-401)

SVR in the IDEAL Trial Accordingto SNP rs12979860 (genotype 1)

(Ge et al., Nature 2009;461:399-401)

0%

20%

40%

60%

80%

100%

TTN=186

CTN=559

CCN=392

Su

stai

ned

vir

olo

gic

al r

esp

on

se (

%)

Geographic Distribution

(Thomas et al, Nature, 2009;461:798-801)

rs12979860 Allele Frequency

12%

39%

49%

37%

16%

47%

C/C C/T T/T

Caucasianancestry

n=871

African Americanancestry

n=191

(Ge et al, Nature, 2009;461:399-401)

Viral Kinetics According to to SNP rs12979860

-3.0

-2.0

-1.0

0

Weeks

Mea

n H

CV

RN

A D

ecre

ase

(Lo

g10 IU

/mL

)

-4.0

-5.0

2 4 120

-6.0

CTTT

CC

p < 0.001

(Thompson et al., Gastroenterology 2010:139;120-9)

Δ H

CV

RN

A (

Lo

g10 I

U/m

L)

CTTT

-3.0

-2.0

-1.0

0

Weeks

-4.0

-5.0

2 4 120

-6.0

CC

Effect on HCV Kinetics(African Americans)

(Thompson et al., Gastroenterology 2010:139;120-9)

VK on High-Dose Peg-IFNa According to IL28B Genotype

-6

-5

-4

-3

-2

-1

0

0 4 8 12 16 20 24

Weeks of therapyH

CV

RN

A r

edu

ctio

n (

Lo

g10

IU/m

L)

TT

CT

NS

P=0.045

P=0.021

P=0.004

P=0.0005

(Chevaliez S, et al., Gastroenterology 2011;141:119-127)

SVR Predictors

Odds Ratio 95% CI p-value

rs12979860 CC vs non-CC 5.2 4.1 6.7 <0.0001

HCV RNA ≤ 600,000 IU/mL 3.1 2.3 4.1 <0.0001

Caucasian vs African American 2.8 2.0 4.0 <0.0001

Hispanic vs African American 2.1 1.3 3.6 0.004

METAVIR score ≤F2 2.7 1.8 4.0 <0.0001

Fasting blood sugar < 5.6 mmol/L 1.7 1.3 2.2 <0.0001

(Thompson et al., Gastroenterology 2010;139:1181-9)

IL28B vs RVR to Predict SVR

Sensitivity (%) Specificity (%) PPV (%) NPV (%)

Caucasian

CC vs non CC 56 (52-60) 79 (76-82) 69 (65-74) 68 (65-71)

RVR vs non RVR 25 (21-29) 96 (94-97) 84 (77-89) 59 (56-62)

(Thompson et al., Gastroenterology 2010;139:1181-9)

89%79%

64%

24%48%

20%0%

50%

100%

< 600 pg/ml > 600 pg/ml TTCT

CC

serum IP-10IL28B genotype

(Darling et al., Hepatology 2010;53:14-22)

Improvement in SVR Prediction by Combining IL28B and IP-10

N=272

Summary

• In patients infected with HCV genotype 1, the rs12979860 genotype:

• Is strongly associated with the SVR

• Explains 60% of the ethnic influence on SVR

• Influences HCV kinetics on therapy

• Is probably a marker of patient cell “resistance“ to the effect of IFN- through mechanisms that remain to be elucidated

II

HCV resistance to DAAs

HCV Quasispecies

Major viral population

Intermediate viral populations

Minor viral populations

Mechanisms of resistance

sensitive

resistant

Mechanisms of Resistance

sensitive

resistant

Drug


sensitive

resistant

Drug

resistant


sensitive

sensitive

resistant

Drug Stop drug

resistant


sensitive

sensitive

resistant

sensitive

resistant

Drug Stop drug

resistant


sensitive

sensitive

resistant

sensitive

resistant + fit

Drug Stop drug

resistant


sensitive

sensitive

resistant

Drug Stop drug

resistant


sensitive

resistant + very fit

sensitive

Chronic HCV infection is curable

by therapy

sensitive

resistant


sensitive

resistant

Drug

resistant


sensitive

resistant

Drug Stop drug

resistant


resistant

HCV resistance to DAAs

HCV Life Cycle

(Popescu & Dubuisson, Biol Cell 2009;102:63-74)

DAAs in Development

• NS3/4A protease inhibitors

• Inhibitors of HCV replication•Nucleoside/nucleotide analogue inhibitors

of RdRp•Non-nucleoside inhibitors of RdRp (NNIs)•NS5A inhibitors•Cyclophylin inhibitors

NS3/4A Protease Inhibitors

Drug Phase Dose DurationMedian/mean log HCV RNA

reduction

Telaprevir (Janssen) Approved 750 mg q8h 14 days -4.4

Boceprevir (Merck) Approved 400 mg tid 7 days -1.6

Simeprevir (Janssen) III 200 mg qd 7 days -4.1

Faldaprevir (BI) III 240 mg qd 14 days -4.0

Danoprevir/r (Roche) II 200 mg q8h 14 days -3.8

Asunaprevir (BMS) II 300 mg bid 3 days -3.3

Sovaprevir (Achillion) II 600 mg qd 5 days -3.8

ABT-450/r (Abbott) II 200 mg qd 3 days -4.1

GS-9451 (Gilead) II 400 mg qd 3 days -3.5

MK-5172 (Merck) II 400 mg qd 7 days -5.4

NS3/4A Protease Inhibitors

(Raney et al., J Biol Chem 2010:285:22725-31)

Asp168

Ala156

Arg155

Thr54

Val36

(Pawlotsky J-M, Ther Adv Gastroenterol 2009;2: 205-219)

Amino Acid Substitutions Associated with PI Resistance

Resistance and Fitness

In vivo

fitness

Resistance

(Kieffer T, et al. Hepatology 2007;46:631-9)

(Reesink HW, et al. Gastroenterology 2006;131:997-1002)

Telaprevir Resistance

-5

-4

-3

-2

-1

0

1

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Study Time (Days)

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL

)

Placebo VX-950 450 mg q8h VX-950 1250 mg q12h

wt

R155K

A156T

A156V

D168Y

MK-5

172

Vanip

revi

r

0

100

200

300

400

500

600

700

EC

50 [

nM

]

Vaniprevir

MK-5172 Resistance Profile

MK-5172

(Merck, unpublished data)

Drug Phase Dose DurationMedian/mean logHCV RNA level

reduction

Sofosbuvir (Gilead) III 400 mg qd 3 days -3.7

Mericitabine (Roche) II 1500 mg bid 14 days -2.7

IDX184 (Idenix) II 100 mg qd 3 days -0.7

VX-135 (ALS-2200, Vertex) II 200 mg qd 7 days -4.5

Nucleoside/Nucleotide Analogue Inhibitors of HCV RdRp

2’C-Me-ATP in the catalytic site

(Migliaccio et al., J Biol Chem 2003;278:49164-70)

HCV Resistance to 2’-C-Methyl Nucleoside Inhibitors

Non-Nucleoside Inhibitors of HCV RdRp (NNIs)

Drug Phase Dose DurationMedian/mean log

HCV RNA reduction

Tegobuvir (Gilead) II 40 mg bid 8 days -1.4

Setrobuvir (Roche) II 800 mg bid 3 days -2.9

BI207127 (BI) II 800 mg q8h 3 days -3.1

ABT-333 (Abbott) II 600 mg bid 2 days -1.5

ABT-072 (Abbott) II 600 mg qd 3 days -1.6

VX-222 (Vertex) II 750 mg bid 3 days -3.7

BMS-791325 (BMS) II ? ? ?

RdRp Resistance Mutations

(courtesy of Isabel Najera, Roche)

FingersThumb

Palm

A

B

C

D

pol

Filibuvir (Pfizer) Resistance in IFN Null-Responders

(Mori et al., EASL 2010)

Thumb 2 domainM423

Filibuvir

NS5A Inhibitors

Drug Phase Dose DurationMedian/mean log

HCV RNA reduction

Daclatasvir (BMS) III 10 mg qd 1 day -3.2

GS-5885 (Gilead) III 30 mg qd 3 days -3.3

PPI-461 (Presidio) Ib 100 mg qd 3 days -3.7

PPI-668 (Presidio) Ib 240 mg qd 3 days -3.7

ACH-2928 (Achillion) Ib 60 mg qd 3 days -3.7

ABT-267 (Abbott) II 200 mg qd 3 days -3.1

GSK2336805 (GSK) II 60 mg qd 1 day -3.0

BMS824393 (BMS) II 50 mg qd 3 days -3.9

IDX719 (Idenix) II 50 mg qd 3 days -3.7

ACH-3102 (Achillion) Ib 50 mg qd 1 day -3.8

BMS-790052 Resistance in vitro

Subtype Sustitution EC50 Fold-changeReplication level (% wt)

1b replicon

wt 2.6±0.3 1 100

L31V 61±15 24 144±47

Y93H 49±13 19 20±7

wt 5.9±3.7 1 100

1a replicon

M28T 4,100±360 360 31±23

Q30H 8,700±1,900 1,900 75±31

Q30R 7,300±1,100 1,100 41±16

L31M 2,100±610 610 55±15

L31V 20,000±6,000 6,000 117±29

Y93C 11,000±4,000 4,000 11±7

(Gao et al., Nature 2010;465:96-100)

Antiviral Efficacy of Cyclophylin Inhibitors

Drug Phase Dose DurationMedian/mean log HCV RNA

reduction

Alisporivir (DEBIO-025) III 1200 mg bid 14 days -3.6

SCY-465 II 900 mg qd 15 days -2.2

Alisporivir Resistance in vitro

3’UTRNS3 NS4

A BNS5A

ANS5B5’UTR neo

HCV

IRES

EMCV

IRES

Domain I Domain II Domain III

36 213 250 342 356 447

R262Q R318WA241P D320E

A241P + R262Q

A241P + R318W

R262Q + R318W

R318W + D320E

A241P + R262Q + R318W

A241P + R262Q + R318W +

D320E

Fold-changevs wt

1.02 1.58 1.37 3.67 1.72 3.89

(Coelmont et al., EASL 2009)

III

Treatment Failure with the Triple Combination of Peg-

IFNa, Ribavirin and Telaprevir or Boceprevir

Pre-existence of PI-resistant HCV variants

Mathematical Modeling

• “…all possible single and double mutants are predicted to be generated multiple times each day“

• “…all viable single and double mutants that confer drug resistance preexist and may compete with the wild-type virus during therapy“

• “[triple mutants] can be selected by sequential mutations when single or double mutants replicate“

(Rong et al., Sci Transl Med 2010;2:30ra32)

Pre-existing HCV Resistant Variants by UDPS

PatientIL28B

genotype

HCV subtype

pegIFN

RBV

TVR

Response

V36A/M

T54A/S V55A Q80

R/KR155K/T/Q

A156S/T/V

D168A/V/T/H

I170A/T

Pt-1 CT 1a NR - 90.0% - - 0.1% 0.4% 0.1% 0.5%Pt-2 CT 1a NR - - - - 0.1% 1.1% - 0.2%Pt-3 CT 1b RR - - - - 0.5% 0.5% - 0.2%Pt-4 TT 1b RR - 29.4% - - - 1.3% - 0.1%Pt-5 CT 1a RR - - - - 0.1% 2.9% 0.1% -Pt-6 CT 1b RR 4.2% - - - 0.1% 0.1% 0.1% 0.1%Pt-7 CT 1a SVR - 11.1% - 0.7% - 0.3% - 0.3%Pt-8 CT 1a SVR - - - - 0.1% 0.5% 0.1% -Pt-9 CC 1a SVR - - - - 0.6% 1.8% - -

Pt-10 CC 1a SVR - - - - 0.6% - - 0.1%Pt-11 TT 1a RR - - 100.0% 0.1% 6.0% 3.2% 0.1% 0.3%Pt-12 CT 1b SVR - - - - - 0.3% - 0.1%Pt-13 CT 1b SVR - - - - 0.2% 0.2% - 0.8%Pt-14 TT 1b NR - - - - 0.1% 0.2% - 0.1%Pt-15 CT 1b SVR - - - - 0.4% 0.2% 0.1% 0.1%Pt-16 CT 1a SVR - - 1.3% 0.5% 7.8% 0.2% 0.1% 0.1%Pt-17 CT 1a SVR - 47.4% - - 0.1% 0.4% 0.1% 0.1%Pt-18 CT 1b SVR - 20.0% - - 0.1% 0.4% 0.1% 0.1%

*SNP rs12979860

(Chevaliez S., et al. EASL 2011)

SVR: sustained virological response; RR: response-relapse; NR: non-response

Summary

• Viruses with amino acid substitutions known to confer resistance to HCV protease inhibitors pre-exist, generally (but not always) as minor viral populations, in 100% of HCV-infected patients

Resistance and PI monotherapy

(Reesink HW, et al. Gastroenterology 2006;131:997-1002)

Telaprevir Resistance

-5

-4

-3

-2

-1

0

1

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Study Time (Days)

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL

)

Placebo VX-950 450 mg q8h VX-950 1250 mg q12h

DAA Resistance

(Pawlotsky JM. Hepatology 2011;53:1742-51)

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL

)

-5

-4

-3

-2

-1

0

1

Wild-type, sensitive HCV

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL

)DAA Resistance


-5

-4

-3

-2

-1

0

1


Resistant HCV

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL

)DAA Resistance


Summary

• The administration of a protease inhibitor alone selects pre-existing resistant viral variant populations, which grow exponentially until they become dominant if treatment is continued

Triple Combination Treatment Failure

Treatment Failures on Triple Combination with a DAA

• Due to an inadequate response to Peg-IFN and ribavirin

• Results in uncontrolled outgrowth of resistant HCV variants selected by the protease inhibitor


SVR According to Lead-in (SPRINT-2, non-black)

29%

39%

82%

% o

f p

atie

nts

wit

h S

VR

0

10

20

30

40

50

60

70

80

90

100

BOC/RGT BOC/PR48

82%

<1 log HCV RNA decrease

≥1 log HCV RNAdecrease

(Poordad et al., N Engl J Med 2011;364:1185-206)

SVR According to Lead-in (RESPOND-2, non-black)

33% 34%

79%

% o

f p

atie

nts

wit

h S

VR

0

10

20

30

40

50

60

70

80

90

100

BOC/RGT BOC/PR48

73%

<1 log HCV RNA decrease

≥1 log HCV RNAdecrease

(Bacon et al., N Engl J Med 2011;364:1207-17)

0

20

40

60

80

100

Pat

ien

ts W

ith

Un

det

ecta

ble

HC

V

RN

A (

%)

Priornull-response

Prior partialresponse

Priorrelapse

(Foster et al., EASL 2011)

REALIZERx-experienced, Gen 1, Telaprevir

62%

94%

56%59%

15%

54%

<1 log decrease

≥1 log decrease

Overall

33%

82%

-5

-4

-3

-2

-1

0

1


Resistant HCV

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL

)DAA Resistance


-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL

)Triple Combo Failure

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL


Potent IFN-ribavirin effect

-5

-4

-3

-2

-1

0

1


Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL



-5

-4

-3

-2

-1

0

1


Resistant HCV

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL



-5

-4

-3

-2

-1

0

1


Resistant HCV

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL



CURED

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL


Moderate IFN-ribavirin effect

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL




-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL




Resistant HCV

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL




Resistant HCV

CUREDor

RELAPSE with RESISTANT VIRUS

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL


Modest or null IFN-ribavirin effect

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL




-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL




Resistant HCV

-5

-4

-3

-2

-1

0

1

Study Time

Med

ian

HC

V R

NA

Ch

ang

e f

rom

Bas

elin

e (L

og

10 IU

/mL




Resistant HCVRELAPSE or BREAKTHROUGH

with RESISTANT VIRUS

Summary

• Treatment failure (i.e. the failure to eradicate HCV infection) with the triple combination of Peg-IFNa, ribavirin and a protease inhibitor is due to an inadequate response to IFNa and ribavirin

• The outgrowth of viral populations resistant to the protease inhibitor is the consequence of treatment failure, not its cause

Treatment failure and resistance in Phase III trials

Dominant virus atthe time of failure

Total n=342*

9743

117

38

32

15

0

50

100

150

200

250

300

Pat

ien

ts,

n

1a 1b

No sequence available

Dominant resistant virus

Dominant wild-type virus

(Zeuzem S., et al., EASL 2011)

Boceprevir Resistance in Patients with Treatment Failure

Frequency and distribution of resistancesubstitutions according to the subtype

(% substitutions detected by subtype)

3

61

60 0

19

3 1

68

8 5 4 07

0 1 1 0 03 3

42

3 3

37

24

0 3 0

26

3 5 5

32

0 0 3 5

0

10

20

30

40

50

60

70

80

90

100

V36A

V36M

T54A

T54C

T54G

T54S

V55A

V55I

R155K

R155T

A156S

A156T

A156V

V158I

V170A

I170

FI1

70T

V170T

M17

5L

Var

ian

ts, %

Subtype 1a

Subtype 1b

(Zeuzem S., et al., EASL 2011)

Boceprevir Resistance in Patients with Treatment Failure

(Chevaliez S., et al., EASL 2011)

0

57

0%

20%

40%

60%

80%

100%

H28Q+R155K

H28Q+R155K+S54T+Y52C

H28Q+R155K+S54T+Y52C+V36M+H57L+P96H

0

2

4

6

8

Days of therapy

% o

f var

iant

s in

the

quas

ispe

cies

*PyroLink®

TVR + PegIFN

HCV

RN

A(Lo

g 10 IU

/mL)

Viral populations

Treatment Failure-PROVE2

Summary

• In Phase III trials, approximately half of the patients who failed to eradicate HCV were infected by dominant viral populations that were resistant to telaprevir or boceprevir at the time of viral escape, depending on the ability of therapy to clear wild-type, sensitive viruses at the time of failure

Post-treatment failure outcome

Median time to wild-type by population sequencing =7 months (95% CI: 5-8)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Pro

bab

ility

0 2 4 6 8 10 12 14 16 18

Time after treatment failure (months)

median

Probability of Telaprevir-Resistant Variant Detection

(Sullivan et al., EASL 2011)

0.6

Pro

bab

ility

Time after failure (months)

0.0

0.1

0.2

0.3

0.4

0.5

0.7

0.8

0.9

1.0

0 2 4 6 8 10 12 14 16 18

median

Probability of Telaprevir-Resistant Variant Detection

(Sullivan et al., EASL 2011)

1a

1b

(Chevaliez S., et al., EASL 2011)H

CV R

NA

(Log

10 IU

/mL)

0

2

4

6

8

Days of treatment

% o

f mut

ation

s in

the

who

le q

uasi

spec

ies

*PyroLink®

0

29

57

85

182

595

686

903

0%

20%

40%

60%

80%

100% H28Q+R155K

H28Q+R155K+S54T+Y52C

H28Q+R155K+S54T+Y52C+V36M+H57L+P96H

V36M+R155K+H57L

R155K

% o

f var

iant

s in

the

quas

ispe

cies

Days of therapy

HCV

RN

A (L

og10

IU/m

L)

Viral populations

Treatment Failure-PROVE2

Genotype 1b

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Time after treatment failure (years)

0 0.5 1 1.5 2

T54AT54SAll

Genotype 1a

% r

esis

tan

t vi

ral v

aria

nts

det

ecte

d

2

Time after treatment failure (years)

0.5 1 1.5 0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

V36M

T54SR155K

All

0

(Barnard et al., CROI 2011)

% V

aria

nt

vir

al r

ésis

tan

t d

étec

té

Post-Failure Follow-up (Boceprevir)

Summary

• The decrease of telaprevir- or boceprevir-resistant viral populations starts immediately after administration of the protease inhibitor is stopped

• This decrease is slow and leads, after a few months to years, to their replacement by a wild-type (i.e. protease inhibitor-sensitive) dominant population, which coexists with minor populations made of resistant viruses, i.e. a situation similar to the pretherapeutic one

Practical role of HCV resistance testing

Viral Sequence Analysis Tools

Population (direct) sequencingReverse hybridization

Reverse hybridizationCloning/sequencing

Next-generation sequencing (UDPS)

Practical Recommendations

• Prior to therapy:

• All patients should be considered as harboring minor viral populations that are resistant to telaprevir and boceprevir

• There is no indication for resistance testing at baseline

Practical Recommendations

• In case of treatment failure:

• Protease inhibitor-resistant viral populations have been enriched in every patient treated with telaprevir or boceprevir who did not clear infection

• There is no indication for resistance testing during and after therapy, as the result will have no impact on treatment decisions

• Resistance testing is required in clinical trials and global surveillance studies (research setting)

IV

HCV Resistance in All-oral, IFN-free regimens

Barrier to Resistance

Low-barrier drug High-barrier drug

• Low barrier to resistance• First-generation protease inhibitors• Non-nucleoside inhibitors of RdRp• NS5A inhibitors (subtype 1a)

• High barrier to resistance• Nucleoside/nucleotide analogues• Cyclophylin inhibitors• NS5A inhibitors (subtypes other than 1a)• 2nd-generation protease and NS5A inhibitors

Barrier to Resistance

GS-9256 (PI) + Tegobuvir (NNI)

0 7 14 21 280

1

2

3

4

5

6

7

8

(<25 IU/mL)HC

V R

NA

IU

/mL

(L

og

)

Days

(Zeuzem et al., Hepatology 2012;55:749-58)

GS-9256 + tegobuvir

Danoprevir (PI) + Mericitabine (NI)INFORM-1 Trial

(Gane et al., Lancet 2010;376:1467-75)

Days DaysDays

Danoprevir, 900 mg bid + RG7128Danoprevir, 900 mg bid + pegIFNand ribavirin Increasing doses of danoprevir and RG7128

(Lok et al., N Engl J Med 2012;366:216-24)

Daclatasvir (NS5A)/Asunaprevir (PI)HCV Genotype 1a

(Suzuki et al., EASL 2012)

Daclatasvir (NS5A)/Asunaprevir (PI)HCV Genotype 1b

Interferon

Health & Medicine

Pawlotsky resistance