5. EPIDEMIOLOGIE DE L'INFECTION A VHB
• Hépatites aigues
– VHA : 40%
– VHB : 30%
– VHC : 20%
• incidence : 300 000 infections à VHB / an
• 30 000 nouveaux porteurs chroniques / an
• 3 000 décès / an
AUX USA
6. MODES DE TRANSMISSION DU VIRUS DE L'HÉPATITE B EN EUROPE
sexuelle
34%
hétéro
23%
homo
11%
drogue IV
26%
inconnue
31%
hémodialysés
8%
transfusions
2%
personnels de santé
2%
contact avec
porteur du VHB
4%
Asie
Transmission verticale
7. Déclaration obligatoire
de l’hépatite B en France :
résultats des 12 premiers mois de notification
Denise Antona, E Delarocque-Astagneau, D Lévy-Bruhl
département des maladies infectieuses
8. Results
158 acute hepatitis cases
• Hospital doctor in 64% cases
• Sex ratio M/F : 2,95 (118/40)
• Median age: 37 yrs for males, 36yrs for females
• Jaundice : 69%
• Hospitalisation : 46%
• Fulminant hepatitis : 3 (2 death)
9. Risk exposure within 6 months preceding the acute case
Source : obligatory declaration 2003-04
• Source: obligatory declaration march 03- february 2004 N=145
– Sexual 59 40,6% No factor 43 29,6%
– IVDU 9 6,2% >1 factor 38 26,3%
– Invasive treatment 15 10,3%
– Tatoo, piercing 5 3,4%
– Familial 14 9,7%
– Perinatal 2 1,4%
– Live in instiution 11 7,6%
– Travel in endemic 21 14,5%
areas
91/145 patients (63 %) had a vaccine indication (2 vaccinated ≥ 3 doses)
• Sentinel networks 91-96
N=195
– sexual 35%
– IVDU 19%
– « percutaneous » 15%
– No factor 35%
10. Surveillance épidémiologique de
l’infection HBV
• 14 446 adultes testés
• Prévalence de l’AgHBs 0,65% (280 000 porteurs
chroniques du VHB)
• Homme 1,1% versus 0,2% femme
• Naissance en zone d’endémie 4% versus 0,5%
• Précarité, séjour en institution, homosexualité,
usage de drogues
Meffre et al, J. Med Virol 2004
11. Hépatites virales B: épidémiologie
- Vaccin mais 250 millions de porteurs
chroniques dans le monde
- 280 000 porteurs chroniques en France (INVS)
- 45% ignorent leur statut
- 1 300 décès par an en France
- 60 000 avec hépatite chronique active
- Environ 15 000 patients traités
13. • FAMILLE : Hepadnaviridae, seul représentant humain
•VIRUSRESISTANT:
-7 jours dans l’environnement
-pendant 5 mnà 100°C,10h à 60°C
-à la congélation.
LE VIRUS DE L ’HEPATITE B
14. S small surface protein
M middle surface protein
L large surface protein
core capsid protein
HBeAg secreted e antigen
pol polymerase
HBx X protein (non-secreted)
v
v
v
sphere
filament
Dane particle
HBeAg
HBsAg
15. The HBV genome
Tiollais, Nature 1985
déterminant a
vaccin/IgHBs
Gène pol
antiviraux
Mt pre-core
Réponse anti-HBe ?
Mt du core
Réponse CTL
8 génotypes
A to H
17. Model for sodium-dependent taurocholic cotransporting
polypeptide (NTCP) binding to preS1
Seeger C , and Mason W S Gut 2013 in press; Yan H, et al. eLife 2012;1:e00049; Hu NJ, et al. Nature
2011;478:408–11.
• Sodium-dependent transporter for taurocholic acid
• Expressed at the basolateral membrane of hepatocytes
• Mediates the transport of conjugated bile acids
• 349 amino acid-long glycosylated transmembrane protein.
• Expression controlled by hepatocyte-specific transcription
factors, including HNF3 and C/EBP
18. Model for sodium-dependent taurocholic cotransporting
polypeptide (NTCP) binding to preS1
Seeger C , and Mason W S Gut 2013 in press; Yan H, et al. eLife 2012;1:e00049; Hu NJ, et al. Nature
2011;478:408–11.
21. Infection à VHB et risque de CHC
• Etude de Beasley à Taiwan
– risque relatif = 100 chez les porteurs de l'AgHBs
• Etude de Tsukuma
– risque cumumatif de CHC à 3 ans
• 12,5% chez 240 patients avec cirrhose
• 3,8% chez 677 patients avec hépatite chronique
– risque x 7 si AgHBs +
– risque X 4 si anti-HCV +
• Facteurs associés : alcool, tabac, aflatoxine
• Diminution incidence avec la vaccination de masse (Chen,
NEJM 1995)
22. CARCINOME HEPATOCELLULAIRE ET VIRUS
DE L'HEPATITE B
• Co-incidence de répartition géographique
VHB / CHC
• Porteurs AgHBs : RR x 100 pour le CHC
• CHC dans les modèles animaux de l'hépatite B :
– marmotte
– écureuil
• Présence d'ADN viral intégré dans les tumeurs
32. Hépatocyte infecté
HBs Ag
Hépatocyte
non infecté
Marqueurs
AgHBe-
anti-HBe +
HBV DNA < 2000 IU/mL
ALAT = N
Foie = rémission
Phase de rémission
portage inactif de l’AgHBs
Réactivation
Virus sauvage
ou mt pre-coreOncogénèse
CD8
CD4
34. cccDNA(copies/cell)
TotalHBVDNA
(copies/cell)
cccDNA levels in the different phases of
chronic HBV infection
• HBeAg+ patients had significantly higher cccDNA (90-fold) and total HBV
DNA (147- fold) levels compared to HBeAg- patients. (p<0.001, Wilcoxon
tests)
10-3
10-2
10-1
100
101
102
103
104
10-3
10-2
10-1
100
101
102
103
Werle et al, Gastroenterology 2004
35. Inactive HBV carrier
● Not virologically inactive:
– low levels of viremia
– episomal HBV DNA in the liver
LOW-REPLICATIVE STATE HIGH-REPLICATIVE STATE
– spontaneously
– during immunosuppression
Low-replicative or latent infection
Epigenetic control
Histones
PCAF
p300 PCAF
p300
Sirt1
Sirt1
HDAC1HDAC1
Histones
Pollicino et al., Gastroenterology 2006
Pollicino et al. Gastroenteroplogy 2006
Levrero et al. J Hepatol, 2009
38. HEPATITE B AIGUE
• Incubation 1 à 6 mois
• Le plus souvent asymptomatique
– Évolution plus fréquente vers la chronicité
• Prodromes:
– Maladie sérique : arthralgies, urticaire,
acrodermatite etc. ..
• Formes ictériques : + graves que VHA et VHC
– Durée de l’ictère : jusqu’à 4 mois
• Evolution : chronicité 5 à 10%
• Hépatites fulminantes
39. Laboratory Diagnosis of Acute Hepatitis B
0
100
200
300
400
500
600
700
800
900
1000
0 1 2 3 4 5 6 12 24 36 48 60
ALT
HBsAg
HBeAg
HBV DNA
Normal
Months After Exposure
Symptoms
Anti-HBs Ab
Anti-HBe Ab
IgM anti-HBc
Total anti-HBc
Seeger, Zoulim, Mason, Fields Virology 2007
40. HEPATITE B PROLONGEE
• Définition
– Persistance réplication virale à la 8ème
semaine d’évolution :
– AgHBe + ou ADN-VHB +
• Evolution
– Chronicité : 8 cas / 10
• Traitement : IFN
– Guérison : 7 à 8 cas / 10
41. INFECTIONS CHRONIQUES A VHB
FORMES CLINIQUES
• virus sauvage
– tolérance immunitaire
– rupture de tolérance -> lésions hépatocytaires : HCA
– séroconversion anti-HBe spontanée (portage inactif) :
5-10% /an
– > diminution significative réplication virale
– > amélioration signes histologiques
• virus muté pré-C (-)
– sélection au moment de la séroconversion anti-HBe
– dépend du génotype viral
– immunopathologie ?
– sévérité de l'hépatopathie : controversée
– association au CHC
42. 0
100
200
300
400
500
600
700
800
0 1 2 3 4 5 6 12 24 36 48 60
ALT
HBsAg
HBeAg
HBV DNA
Normal
Months After Exposure
Laboratory Diagnosis of Chronic Hepatitis B
associated with wild type virus infection
Seeger, Zoulim, Mason, Fields Virology 2007
43. ALT
``HBsAg
HBeAg
HBV DNA
Normal
Months After Exposure
Anti-HBe
Laboratory Diagnosis of Transition of Chronic
Hepatitis B to The inactive Carrier State
0
100
200
300
400
500
600
700
800
0 1 2 3 4 5 6 12 24 36 48 60 72 80 92 104
Seeger, Zoulim, Mason, Fields Virology 2007
44. 0
50
100
150
200
250
300
350
400
450
0 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48
ALT
HBsAg
HBV DNA
Normal ALT levels
Months
Anti-HBeHBeAg
Laboratory Diagnosis of HBeAg negative
Chronic Hepatitis B
Seeger, Zoulim, Mason, Fields Virology 2007
59. VARIABILITE GENETIQUE DU VHB
• Multiplication virale
» taux d'erreur de la transcriptase inverse
• Pression de sélection
» réponse immunitaire cellulaire / humorale
» antiviraux
-> possibilité de variants d'échappement
• Conséquences cliniques
» diagnostic sérologique
» traitements antiviraux
60. 8 genotypes, numerous sub-genotypes, and
recombinant forms
World J Gastroenterol 2007; 13: 14-21
B6
D1
61. Génotypes VHB chez les patients atteints
d’hépatite chronique en FranceNumberofsubjects
F GA B C D E
0
10
20
30
40
50
60
70
80
90
100
30.2%
7.9%
12.5%
37.4%
11.3%
0.4 % 1.1%
Zoulim et al J Viral Hepatitis 2006
62. Impact du génotype sur la
séroconversion Hbe/HBs
1 Janssen, Lancet 2005; 2 Flink, Am J Gastro 2006
PEG-IFN a-2b
HBeAg Loss 1
0
10
20
30
40
50
A
n=90
28%
47%
44%
25%
B
n=23
C
n=39
D
n=103
Percentageofpatients(%)
HBV genotype
0
3
6
9
12
15
A
n=90
5%
8%
0%
B
n=23
C
n=39
D
n=103
18
15%
Percentageofpatients(%)
21
HBV genotype
PEG-IFN a-2b
HBsAg Loss 2
63. LES MUTANTS DU GÉNOME DU VHB
déterminant a
vaccin/HBIg
polymérase
antiviraux
Mt pré-core
Réponse anti-e ?
Mt core
Réponse CTL
64. ROLE DE LA RÉGION PRÉ-C ET DE L’AgHBe
• Non nécessaire à la réplication du VHB
– Culture cellulaire
– Modèles in vivo
• Marmotte
• Canard
• Modulation de la réponse immune
– Tolérogène : souris transgéniques
– Cible de la réponse anti-capside
Chang et al, J. Virol 1987; Schlicht et al J. Virol 1987; Chen J. Virol 1992; Millich et al PNAS
65. LES MUTANTS PRÉ-C (-)
• codon stop / région pré-C
TGG -> TAG en pos. 1896
– génotypes B à E (A : exceptionnel)
– arrêt traduction protéine pré-C/C
– AgHBe négatif
• mutation dans promoteur pré-C
TTAAAGG -> TTAATGA en pos. 1762 /1764
– génotypes A à E
– transcrits pré-C/C :
– synthèse d'AgHBe :
Carman et al Lancet 1989, Okamoto et al J Virol 1990/1994, Tong et al Virology 1990
66. HBeAg and Precore Mutation
1814 1901
Precore Core
region region
HBcAg
HBeAg
G 1896A = stop codon, TAG
ATG ATG
Virion
Serum
Core gene
67. HBeAg and Precore Mutation
1814 1901
Precore Core
region region
HBcAg
HBeAg
ATG ATG
Virion
Serum
Core gene
68. VARIANTS NÉGATIFS POUR L ’AgHBe
mRNA
Protéine
pré-C/C
PRE-C CPROMOTEUR
TAG
***
1762-1764 1896
arrêt des synthèses protéiques
Diminution de l’expression de l ’AgHBe
69. Sélection des mutants pré-core au cours de
l’histoire naturelle de l’hépatite B chronique
0
500
1000
1500
2000
2500
temps
ALAT
ADN-VHB
AgHBe Anti-HBe
0
20
40
60
80
100
temps
sauvage
Mt pré-C
70. Outcome of Chronic Anti-HBe Positive Hepatitis B
0
100
200
300
400
0
100
200
300
400
0
100
200
300
400
Biochemical patterns in 164 untreated patients
after 23 months (range 12-36) monthly monitoring
0 12 24
months
With flares and normalization
Without flares
With flares and without normalization
73 pts
( 44.5% )
59 pts
( 36.0% )
32 pts
( 19.5% )
Asymptomatic
flare-up:
90% of cases
A
L
T Flare-up yearly
frequency:
once 57.1%
twice 20%
< once 22.8%
Brunetto MR et al, J Hepatol 2002
71. Augmentation de prévalence des hépatites
chroniques avec AgHBe négatif en France
HBeAg(+)
HBeAg(-)
42%
N=119
58 %
N=164
Zoulim et al, J Viral Hepatitis 2006
73. Diagnosis of inactive carrier versus
HBeAg negative chronic hepatitis
• Inactive Carrier
– Persistently normal ALT levels
– Persistently low levels of serum HBV DNA
Threshold : 2,000 IU/ mL (see EASL CPG J Hepatol 2009/2012)
• HBeAg negative chronic hepatitis
– Fluctuation / exacerbation of ALT
– Fluctuations of HBV DNA levels usually > 2000 IU/ mL
– Presence of pre-core / core promoter mutations
74. DIAGNOSTIC D'UNE EXACERBATION AIGUE
SUR HEPATITE B CHRONIQUE
• Définition : poussée cytolytique
≠ réactivation virale
• Ag HBe + initialement
– rupture de tolérance immunitaire
– séroconversion anti-HBe
– très fréquent chez patients asiatiques
• Anti-HBe + initialement
– réactivation virus sauvage : -> AgHBe +
– réactivation virus muté pré-C (-)
– Corticothérapie, biothérapie, chimiothérapie
– surinfection delta / VHC
75. COOH
137
149
107
99 NH2
S - S
S - S S - S
S-S
138
139
147
Tiollais P. et al., Nature 1985. Torresi J., J. Clin Virol 2002; Dryden KA. et al., Mol Cell 2006
« a » determinant
HBs Ag
« a » determinant induces the synthesis of
anti-HBs neutralizing antibodies
sG145R
sP120T
sD144H/A/E
PreS1
PreS2
SPol
Pré-C
C
Brin(+) 2,4kb
Brin(-) 3,2kb
X
TATAA
U5-like
DR1
DR2
Enh1Enh2
0/3221
SHBs (S)
MHBs (preS2+S)
LHBs (preS2+preS2+S)
76. Variants de l'Ag HBs
• échappement à la réponse humorale anti-HBs
– naturelle
– vaccination (transmission mère-enfant)
– immunoprophylaxie (transplantation hépatique)
• infection active malgré Ac anti-HBs
• sérologie AgHBs faussement négative
Risques : transmission virale + infections occultes
77. VARIANTS DE L'AgHBs
• Mutations ponctuelles dans le déterminant a de
l'AgHBs (124-147)
– aa 145 : Gly -> Arg
– aa 126 : Ile -> Ser / Thr -> Asn
• transmission mère-enfant malgré la serovaccination
(3%)
• infection du greffon hépatique malgré
Immunoglobulines anti-HBs
• hépatites chroniques avec anti-HBc et anti-HBs +
78. Presence of HBV DNA in the liver ( serum) of
individuals testing HBsAg negative by currently
available assays
Occult HBV Infection (OBI)
Raimondo et al, J Hepatol 2008
79. How to Detect Occult HBV Infection
Currently there is no standardized
diagnostic assay for occult HBV infection
80. Reported Prevalence of Occult HBV Infection in HIV Positive Patients
Study Country N° of
patients
Occult
HBV
N° (%)
Methods
Hofer, 1998 Switzerland 57 51 (89%) “nested” PCR
(serial evaluation)
Torres-Baranda, 2006 Mexico 35
7 (20%) “nested” PCR
Filippini, 2006 Italy 86 17 (20%) single step PCR
Mphahlele, 2006 South Africa 140 31 (22.%) “nested” PCR
Pogany, 2005 Netherlands 93 4 (4%) single step PCR
Neau, 2005 France 160 1 (0.6%)
Santos, 2003 Brazil 101 16 (16%) single step PCR
Wagner, 2004 France 30 11 (37%) “nested” PCR
Goncales, 2003 Brazil 159 8 (5%) “nested” PCR
Nunez, 2002 Spain 85 0 Cobas Amplicor HBV
Monitor (Roche)
Piroth, 2000 France 37 13 (35%) single step PCR
Raffa, 2007 Italy “nested” PCR (liver)
Cobas Amplicor HBV
Monitor (Roche)
101 42 (41%)
Raimondo et al, J Hepaol 2007, modified
81. OBI
Cause(s) for the
failure of HBsAg detection
Suppression of
HBV replication and
gene expression
Infection by
S gene Variants
“false” OBI
82. Occult HBV infection
HBV cccDNA Integrated HBV DNA
HBV mutants Epigenetic control
HBV replication
Immune surveillance
Viral co-infections
83. OBI
Seropositive Seronegative
HBsAg lost
during CH
HBsAg lost
after AH
Progressive antibody
disappearence
Primary occult
Schematic representation of HBV serum marker profile in OBI and
“false” OBI
„false“ OBI
S gene
escape mutants
HBV DNA levels
comparable to
overt infection
HBV DNA levels
< 200 UI/ml
86. HBeAg(+) HBeAg(-) / anti-HBe(+)
ALAT
HBV DNA
Minimal CH Moderate to severe CH Moderate to severe CHRemission
Cirrhosis
Immunotolerant
phase
Immuno-active
phase
Inactive phase
Low replication
Reactivation phase
Cirrhosis
109-1012 IU/mL >2000-<109 IU/mL <2000 IU/mL >2000 IU/mL
Inactive cirrhosis
Adapted from Fattovich G. Sem Liver Dis. 2003
Treatment indicated Treatment indicated
HBsAg
Occult infection
87. Antivirals approved for hepatitis B
*Currently approved for HIV
**development on hold
Drug Type Approved Phase 3 Phase 2
Nucleoside analogs • Lamivudine*
• Entecavir
• Telbivudine
• Emtricitabine*
• Clevudine**
Nucleotide analogs • Adefovir dipivoxil
• Tenofovir*
Cytokines • Interferon alfa
• Pegylated Interferon
alfa-2a
• TLR7 agonists
•IL7
•IFN Lambda
•Vaccine therapy
88. Endpoints of therapy
Persistence of high viral load is associated with a significant risk of progression of
the liver disease and of HCC
Aim of antiviral therapy:
HBV DNA < 10-15 IU/mL by real-time PCR assays
No replication
=
No resistance
Viral suppression
Histological and clinical
improvement
Chen CJ, et al. JAMA 2006. Iloeje UH, et al. Gastroenterology 2006. Chen C, et al.
Am J Gastroenterol 2006. Zoulim & Perrillo J Hepatol 2008. Zoulim & Locarnini Gastroenterology 2009
89. Treatment failure
Primary non response
Partial response
Secondary treatment failure
Antiviral drug resistance
Host factors
Drug metabolism
Patient’s compliance
Drug factors
Antiviral potency
Drug factors
Barrier to resistance
Viral factors
Resistant mutants
Zoulim et al Hepatol 2008; EASL CPG J Hepatol 2009; Lancet Infect Dis 2012
90. Clinical definition of resistance
• Virologic Breakthrough: Rebound in serum HBV DNA levels
(e.g. 1 log10 above nadir)
• Genotypic Resistance: Detection of mutations known to
confer resistance while on therapy
• Virologic Breakthrough with Genotypic Resistance: Viral
rebound associated with a mutation(s) known to cause
resistance.
• Primary non response: <1log10 decrease of viral load after 3
months
• Partial response: detectable HBV DNA levels during therapy
Zoulim & Perrillo, J Hepatol 2008; EASL CPG, J Hepatol 2009
91. Laboratory Definition of HBV Resistance to Antivirals
Laboratory Investigations
• Phenotypic Resistance: Decreased susceptibility (in vitro
testing) to inhibition by anti-viral drugs associated with
genotypic resistance.
• Cross Resistance: Mutants selected by one agent that also
confer resistance to other antiviral agents
Zoulim et al; Future Virology 2006
92. The main differences between HIV,
HBV and HCV
H
HBV1,2
Host cell
cccDNA
Host DNA
Integrated DNA
Nucleus
H
HIV1
Host cell
Host DNA
Proviral DNA
Nucleus
H
HCV1,3
Host cell
Host DNA
Nucleus
HCV RNA
Life-long suppression
of viral replication
Definitive viral clearance
and SVR
Long-term suppression
of viral replication
Adapted from 1. Sorriano V, et al. J Antimicrob Chemother 2008;62:1-4. 2. Locarnini S and Zoulim F. Antiviral Therapy 2010;15 (suppl 3):3-14. 3.
Sarrazin C and Zeuzem S. Gastroenterology 2010;138:447-462.
93. Si Ahmed et al. Hepatology. 2000; Yuen et al Hepatology 2001; Locarnini et al Antiviral Therapy 2004;
Villet et al Gastroenterology 2006 J Hepatol 2007 & 2008; Pallier et al J Virol 2007; Yim et al Hepatology 2006.
Kinetics of emergence of HBV drug resistant mutants
95. Biochemical and Histologic
Correlates of HBV Resistance
• Rise in ALT levels
– Mild ALT elevations in most cases
– ALT flares with acute exacerbations and liver failure:
especially patients with liver cirrhosis and/or pre-core
mutant infection
• Progression of liver disease
– Progressive worsening of liver histology
– Clinical deterioration, liver decompensation, HCC
development
Lai et al Clin Infect Dis 2003; 36: 687-696; Dienstag et al Gastroenterology 2003;124:105-117 ; Lok et al Gastroenterology
2003; 125 : 1714-1722; Hadziyannis et al Hepatology 2000;32:847-851; Si Ahmed et al Hepatology 2000; Zoulim et al J Viral
Hepatitis 2006;13:278-288 ; Fung et al J Hepatol 2005;43:937-943; Liaw et al NEJM 2004;351:1521-1531.
96. ALT flares in patients with lamivudine
resistance over time
Lok et al Gastroenterology 2003; 125 : 1714-1722
97. 6
3
LVD ADV LdT ETV TDF
0
10
20
30
40
50
60
70
80
23
Proportionofpatients(%)
46
55
71
80
0
11
18
29
5
25
0.2 0.5
1.2
0
1 2 3 4 5 1 2 3 4 5 1 2 1 2 3 4 5 1 2 3
0 0
Option to add
emtricitabine at
week 72*
*Patients confirmed to be viraemic at Week 72 or beyond could add emtricitabine to TDF at the discretion of the investigator.
Clinical data on the safety and efficacy of emtricitabine and TDF in CHB are pending
Rates of resistance with lamivudine (LVD), adefovir (ADV), telbivudine (LdT),
entecavir (ETV) and tenofovir (TDF) among NA-naïve patients
4
0
High barrier to resistance
Adapted from Gish, Jia, Locarnini & Zoulim, Lancet Infect Dis 2012
98. Drug and patient population
Resistance at year of therapy expressed as percentage of
patients
1 2 3 4 5 6
Lamivudine 23 46 55 71 80 -
Telbivudine HBeAg-Pos 4.4 21 - - - -
Telbivudine HBeAg-Neg 2.7 8.6 - - - -
Adefovir HBeAg-Neg 0 3 6 18 29 -
Adefovir (LAM-resistant) Up to 20% - - - - -
Tenofovir 0 0 0 0 0 0
Entecavir (naïve) 0.2 0.5 1.2 1.2 1.2 1.2
Entecavir (LAM resistant) 6 15 36 46 51 57
Incidence of drug resistance over time
CL Lai Clin Infect Dis 2003; CL Lai NEJM 2007; Hadzyiannis Gastroenterology 2006;
Marcellin NEJM 2008; CL Lai & Chang NEJM 2006; Zoulim & Locarnini Gastroenterology 2009
99. Terminal
protein
Spacer POL/RT RNaseH
1 183 349 (rt) 692 (rt 344) 845 a.a.
I(G) II(F) A B C D E
F_V_LLAQ_YMDD
*rtA181T/V and/or rtN236T cause reduced sensitivity
*rtA194T association with rtL180M+rtM204V (to be confirmed)
LMV resistance/ rtL80I
rtL180M
rtM204V/I
LdT resistance
rtA181T/V
ADV resistance rtA181T/V rtN236T
TDF resistance* ?
ETV resistance rtL180M rtM204I/V
rtT184*** rtS202**** rtM250I/V
rtl169T
***S/A/I/L/G/C/M
****C/G/I
Zoulim F & Locarnini Gastroenterology 2009;137:1593-1608.
rtV173L
* Role of complex mutants: rtA181T+rtN236T ?
101. Multiple factors are associated with the
barrier of resistance & drug efficacy
•Adherence
•Immune status
•Prior antiviral exposure
•Metabolism
•Body mass
Patient
Antiviral
Drug
•Antiviral potency
•Number of mutations needed
to overcome drug
suppression
•Level of exposure to drug
•Chemical structure Virus
Locarnini S, et al. Antivir Ther. 2004;9:679–93. Locarnini S, et al. Antivir Ther. 2007;12:H15-H23. 3. Ghany M & Liang TJ. Gastroenterology 2007;132:1574-85. Zoulim F, et al.
Antiviral Res. 2004;64:1-15. Locarnini S, et al. J Hepatol. 2003;39:S124-S132.; Zoulim & Locarnini Gastroenterology 2009
•Replication fitness and space
•Persistence of archived
mutations as cccDNA
•Pre-existing mutations
102. Adherence to nucleos(t)ide analogues for chronic hepatitis B in
clinical practice and correlation with virological breakthroughs
W. Chotiyaputta et al, Journal of Viral Hepatitis, Volume 19, Issue 3, pages 205-212, 14 JUL 2011
105. uncoating CCC DNA
removal of protein primer
removal of RNA primer
completion of viral (+) strand DNA
ligation of DNA strands extremities
supercoiled DNA
minichromosome
viral polymerase?
DNA repair protein?
other cellular enzymes?
Topoisomerase (TDP2) ?
Acetyl transferase ?
Histones
Formation of the recalcitrant cccDNA: a difficult
target for antiviral therapy
Tuttleman et al Cell 1986
Le Guerhier et al AAC 2000
Delmas et al AAC 2002
Kock et al Hepatology 2003
Cortes Ledesma et al Nature 2009
Antivirals ?
106. Can we prevent cccDNA formation ?
Nucleoside analogs in monotherapy or
combination therapy cannot prevent the de
novo formation of cccDNA in hepatocyte
culture and in vivo in animal experiments
(Delmas et al AAC 2000; Seigneres et al AAC 2002)
Can we clear cccDNA from a chronically
infected cell ?
The decrease of intrahepatic cccDNA during
nucleoside analog requires hepatocyte turn
over in animal experiments
(Zhu et al J Virol 2001; Litwin et al J Clin Virol 2005)
107. Kinetics of Viral Loss During Antiviral Therapy with L-
FMAU (clevudine) in the woodchuck model
Zhu et al, J Virol 2001
108. ADV Associated Serum HBsAg Reductions are
Similar in Magnitude to cccDNA Reductions
-6
-5
-4
-3
-2
-1
0
ChangesinHBVMarkers
fromBaseline
(log10copies/cell(ml))
Serum
HBV
DNA
Total
Intracellular
DNA
cccDNA Serum
HBsAg
48 weeks of ADV resulted in significant reductions in :
serum HBV DNA > total intrahepatic HBV DNA > cccDNA
Changes in HBsAg levels correlated with cccDNA changes
-> 14 years of therapy to clear completely viral cccDNA
Werle et al, Gastroenterology 2004
109. • 0.8 log10 (84%) decline in cccDNA, not paralleled by a similar decline in the number of
HBcAg+ cells
• Suggests cccDNA depleted primarily by non-cytopathic mechanisms or that cell turn-over
occurred but was associated with infection of new cells during therapy
Immunohistochemical Staining of Patient Biopsies at
Baseline and After 48 Weeks ADV Therapy
Baseline Week 48
110. Maynard et al, J Hepatol 2005
Persistence of cccDNA after HBs seroconversion
111. Clearance of viral infection versus selection of
escape mutants
The most important factors to consider:
§ The rate of immune killing of infected hepatocytes
§ The rate of replication and spread of mutant virus in the
chronically infected liver (I.e. fitness of the virus: the rate of
spread to uninfected hepatocytes)
§ Small changes in these factors may have profound effect on
whether treatment response is durable or subject to rapid
rebound (Litwin et al J Clin Virol 2005)
§ These factors may be subject to therapeutic intervention
112. Kinetics of spread and emergence of drug
resistant virus during antiviral therapy
Zhou T, et al. Antimicrobial Agents and Chemotherapy 1999; 43: 1947-1954.
antiviral
wt
ni
Free liver space
Mutant fitness
I II III IV
INHIBITION OF WILD TYPE VIRUS REPLICATIONS DELAYED EMERGENCE OF
DRUG RESISTANT VIRUS
ni = non-infected
wt = wild type
mt = mutant type
mt
113. Kinetics of HBV drug resistance emergence
Si Ahmed et al. Hepatology. 2000; Yuen et al Hepatology 2001; Locarnini et al Antiviral Therapy 2004; Villet et al Gastroenterology 2006
J Hepatol 2007 & 2008; Pallier et al J Virol 2007; Yim et al Hepatology 2006.
Treatment begins
Drug-resistant variant
Drug-susceptible virus
Naturally—occurring viral variants
Time
HBVreplication
Primary resistance
mutations
Secondary resistance mutations
/ compensatory resistance mutations
114. Definition of fitness
• A parameter that quantifies the adaptation of an
organism or a virus to a given environment
• For a virus, ability to produce infectious progeny
relative to a reference viral clone, in a defined
environment
Esteban Domingo, In Fields Virology 2007
115. Cross-resistance data for the main mutants and the commercially
available drugs
Zoulim & Locarnini Gastroenterology 2009; Liver Int 2013
Pathway Amino Acid
Substitutions in the
rt Domain
LMV LdT ETV ADV TFV
Wild-type S S S S S
L-Nucleoside
(LMV/LdT)
M204I/V R R I S S
Acyclic
phosphonate (ADV)
N236T S S S R I
Shared (LMV, LdT,
ADV)
A181T/V R R S R I
Double (ADV, TFV) A181T/V + N236T R R S R R
D-Cyclopentane
(ETV)
L180M+M204V/I
± I169 ± T184
± S202 ± M250
R R R S S
Multi-Drug
Resistance
A181T+N236T+
M250V
R R R R R
116. • cccDNA in the liver:
– Is propagated during the normal
replication cycle of HBV
– Can serve as a template for the
production of new virus
Archiving of viral variants
Viral quasispecies
cccDNA variants
Liver
Majority population
Minority variants
Resistant variants
Blood circulation
Zhou et al, AAC 1999; Zoulim F. Antivir Res. 2004. Zoulim F & Perillo R. J Hepatol. 2008
117. • cccDNA in the liver:
– Is propagated during the normal replication
cycle of HBV
– Can serve as a template for the production of
new virus
• It is believed that viral variants with antiviral
resistance may be archived in this way
Archiving of viral variants
Viral quasispecies
cccDNA variants
Blood circulation
Liver
Majority population
Minority variants
Resistant variants
Zhou et al, AAC 1999; Zoulim F. Antivir Res. 2004. Zoulim F & Perillo R. J Hepatol. 2008
118. • cccDNA in the liver:
– Is propagated during the normal replication
cycle of HBV
– Can serve as a template for the production of
new virus
• It is believed that viral variants with antiviral
resistance may be archived in this way
Archiving of viral variants
Viral quasispecies
cccDNA variants
Liver
Majority population
Minority variants
Resistant variants
Blood circulation
Zhou et al, AAC 1999; Zoulim F. Antivir Res. 2004. Zoulim F & Perillo R. J Hepatol. 2008
119. Phenotyping of HBV clinical isolates
1. Durantel D, et al., Hepatology, 2004;40:855-64. 2. Yang H, et al., Antiv Ther, 2005;10:625-33.
Southern blot
analysis
Patient
serum
PCR
cloning
Whole genome
HBV clones
Transfection
HepG2
Huh7
IC50 reference strain
IC50 mutant
Fold resistance
=
Wild-type
virus
Increasing antiviral concentration
Cell culture plate
Patient’s
virus
SS -
RC
-
lamivudine adefovir
120.
121.
122.
123.
124.
125. ADV rtN236T +/or rtA181V
Wild-type virus
ADV-resistant virus
LAM-resistant virus
LAM rtM204V/I ± rtL180M
ETV-resistant virus
rtT184 or rtS202 or rtM250
ETV
rtM204V/I rtL180M+/-
TDF
TDF: what can
we expect?
rtM204V/I +/- rtL180M
LAM
then ETV
rtT184 or rtS202 or rtM250
LAM + TDF – what
do we see?
Maximising the barrier to resistance
126. Can we detect low frequency mutants prior to or
during therapy ?
Use of pyrosequencing to detect
low frequency mutants
•May detect mutants representing
as low as 0.1% of the viral
population
•The clinical significance for
treatment choice or adaptation
needs to be determined by
prospective studies
127. Important factors involved in selection of
MDR mutants
• Use of inadequate sequential monotherapies and inadequate treatment
adaptation
• Incomplete viral suppression
– > Persistent replication in the presence of antiviral pressure
• Use of drugs sharing cross-resistance characteristics
– One mutation may confer resistance to several drugs
– > Persistent replication
• Accumulation of mutations
• Wide replication space (liver transplantation)
128. ?
Multiple drug
resistant mutants
with complex
pattern of
mutations
+ one mutation + one mutation
Drug A Drug B
Risk of selection of MDR mutants by sequential therapy
- drugs sharing cross-resistance characteristics
- incomplete viral suppression
- liver transplantation
The problem of sequential therapy with
nucleoside analogues
Zoulim F, et al. J Hepatol. 2008;48:S2-19.
Yim et al, Hepatology 2006; Villet et al Gastroenterology 2006 & 2009
131. Warner et al Hepatology 2009
Kamili et al Hepatology 2009
Villet et al Gastroenterology 2009
Impact on virus infectivity and fitness
Impact on virion release (intracellular
retention) and virologic monitoring of
breakthrough
Impact on vaccine prophylaxis efficacy
132. Virologic Consequences of Persistent Viremia
Infection of new hepatocytes
slower kinetics of clearance infected cells and
cccDNA
Increases the risk of occurrence and subsequent selection
of HBV mutations responsible for drug resistance
On-treatment prediction of HBV drug resistance
Le Guerhier et al Antimicrob Agents Chemoter 2000;44:111-122; Delmas et al Antimicrob Agents
Chemother 2002; 46:425-433; Kock et al Hepatology2003; 38:1410-1418; Richman Hepatology
2000;32:866-867
133. Perspectives / Prevention of drug resistance
• First line therapy
– Use of antivirals with high antiviral potency and high barrier to
resistance
– Combination therapy with complementary drugs to increase the
barrier to resistance
• Second line treatment
– Add-on strategies with complementary drugs preferred to
sequential monotherapies
– Early treatment adaptation to prevent accumulation of
mutations
– Choice always based on cross-resistance data
134. Prevention of resistance
Impact of first line therapy
• Choose an antiviral drug with
1. A potent antiviral activity
2. A high barrier to resistance
135. 6
3
LVD ADV LdT ETV TDF
0
10
20
30
40
50
60
70
80
23
Proportionofpatients(%)
46
55
71
80
0
11
18
29
5
25
0.2 0.5
1.2 0
1 2 3 4 5 1 2 3 4 5 1 2 1 2 3 4 5 1 2 3
0 0
Option to add
emtricitabine at
week 72*
*Patients confirmed to be viraemic at Week 72 or beyond could add emtricitabine to TDF at the discretion of the investigator.
Clinical data on the safety and efficacy of emtricitabine and TDF in CHB are pending
Rates of resistance with lamivudine (LVD), adefovir (ADV), telbivudine (LdT),
entecavir (ETV) and tenofovir (TDF) among NA-naïve patients
4
0
High barrier to resistance
5
0
Gish, Jia, Locarnini, Zoulim, Lancet Infect Dis 2012
136. Management of partial response – The case of Entecavir
Zoutendijk et al, HepatologyVolume 54, Issue 2, pages 443-451, 25 JUL 2011
Kaplan-Meier curve for the probability of achieving virological response for 243 NA-naïve patients according to HBeAg status
at baseline. P value was determined using log-rank testing.
137. Entecavir treatment for chronic hepatitis B: Adaptation is not needed for the majority
of naïve patients with a partial virological response
Zoutendijk et al Hepatology Volume 54, Issue 2, pages 443-451, 25 JUL 2011
.Kaplan-Meier curve for the probability of achieving a VR for NA-naïve patients with a PVR according to HBV DNA at week 48.
Three patients were switched to TDF plus emtricitabine, and one patient received TDF add-on therapy. P value was determined using
log-rank testing.
138. Zoulim & Locarnini, Gastroenterology 2009; EASL CPG J Hepatol 2009 & 2012
Mangement of antiviral drug resistance
• Impact of second line therapy
– Early treatment adaptation to prevent accumulation of
mutations
– Choice always based on cross-resistance data
– Add-on strategy versus switch ?
• Good results with TDF switch
• Some cases of suboptimal responses
• Combination to increase the barrier to resistance
139. Cross-resistance data for the main mutants and the commercially
available drugs
Zoulim & Locarnini Gastroenterology 2009; Liver Int 2013
Pathway Amino Acid
Substitutions in the
rt Domain
LMV LdT ETV ADV TFV
Wild-type S S S S S
L-Nucleoside
(LMV/LdT)
M204I/V R R I S S
Acyclic
phosphonate (ADV)
N236T S S S R I
Shared (LMV, LdT,
ADV)
A181T/V R R S R I
Double (ADV, TFV) A181T/V + N236T R R S R R
D-Cyclopentane
(ETV)
L180M+M204V/I
± I169 ± T184
± S202 ± M250
R R R S S
Multi-Drug
Resistance
A181T+N236T+
M250V
R R R R R
140. Manns M, et al., EASL 2008; Oral # 1587.
Tenofovir efficacy in LAM Experienced vs. Naïve
Study 103:
N=176
Study 102:
N=250 Total
LAM-Naïve, n
LAM-Experienced, n
168
8
209
41
377
49
• Study 102 actively
enrolled both
LAM experienced and
LAM-naïve patients
• Study 103 enrolled
eight LAM experienced
patients despite
LAM-naïve inclusion
criteria
P=0.718
88%
86%
P=
Naive (N=377)
Lam Exp (N=49)
Percentage(%)
0
10
20
30
40
50
60
70
80
90
100
Weeks on Study
0 4 8 12 16 20 24 28 32 36 40 44 48
88%
86%
P=
Naive (N=377)
Lam Exp (N=49)
Percentage(%)
0
10
20
30
40
50
60
70
80
90
100
Weeks on Study
0 4 8 12 16 20 24 28 32 36 40 44 48
ITT Missing=Failure
Combined data includes both HBeAg +/- patients
141. Reijnders, JGP et al. J Hepatol 2010
Virologic response to Entecavir according to
Lamivudine exposure%Cumulatedresponse
2 80 10 124 6
0
20
60
80
40
100
LVD-naïve (N=118)
LVD-experienced without development of LVD-resistance (N=20)
LVD-experienced with a prior history of
LVD-resistance (N=14)
LVD-experienced with LVD-resistant mutations at baseline (N=9)
P = 0.007
142. 2 80 10 124 6
0
100
20
60
80
40
Reijnders, JGP et al.. J Hepatol. 2010
Virologic response to Entecavir
according to Adefovir exposure
ADV-naïve (N=119)
ADV-experienced without development of
ADV-resistance (N=30)
ADV-experienced with ADV-resistant mutations at baseline
(N=12)
%Cumulatedresponse
P = NS
143. 29 29 29 29 27 26 24 24
33 33 33 31 30 29 27 26
14 14 14 14 14 14 14 14
11 11 11 11 10 10 10 10
17 16 16 16 16 16 16 16
12 12 12 12 12 11 10 10
n =
n =
n =
n =
n =
n =
Response by Baseline Resistance at Week 168
TDF vs. FTC/TDF for Treatment-Experienced Patients:
Weeks on Study
Berg et al, Gastroenterology 2010; Ms submitted
144. Patients heavily exposed to NUCs with low barrier to
resistance – Risk of MDR selection
• Risk of multidrug resistance by sequential
accumulation of resistance mutations
• Risk of partial response, even with the newest NUCs
-> long-term impact ?
145. ?
Multiple drug
resistant mutants
with complex
pattern of
mutations
+ one mutation + one mutation
Drug A Drug B
Risk of selection of MDR mutants by sequential therapy
- drugs sharing cross-resistance characteristics
- incomplete viral suppression
- liver transplantation
The problem of sequential therapy with
nucleoside analogues
Zoulim F, et al. J Hepatol. 2008;48:S2-19.Yim et al, Hepatology 2006; Villet et al Gastroenterology 2006 & 2009
146. Liu et al, Antivir Ther. 2010;15(8):1185-90.
Sequential therapy with NUCs and the risk of MDR
Accumulation of
multiple mutations on
the same viral genome
Complete change of
the viral quasi-species
150. Virologic response to TDF according to ADV resistance
mutations at baseline
The Australian Experience
Patterson S J et al. Gut 2011;60:247-254
151. Tenofovir + Emtricitabine in patients with treatment failure –
treatment intensification
0
1
2
3
4
5
6
7
Baseline M3 M6 M12
Time after TDF+FTC initiation
(months)
HBVDNA(log10
IU/mL)
HBV DNA kinetics after TDF+FTC initiation in 59 patients with treatment
intensification
Si-Ahmed et al, Antiviral Research 2011
Time to undetectable DNA (<50 IU/mL)
14121086420
Probability
1,0
,8
,6
,4
,2
0,0
≤ 4 logs
> 4 logs
Viral load initiation
152. Rescue therapy with ETV + TDF in CHB patients with advanced liver disease and complex viral resistance patterns or
showing partial antiviral responses to preceeding therapies (Virgil network)
ETV + TDF combination in patients
with treatment failure
Petersen J, et al. J Hepatol 2012
HBV DNA Viremia
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
Baseline 3 6 9 12 15 18 21 24
10 6
Δ 3 log10 c/mL reduction
P=0.0001
LLoD
HBVDNA[IU/ml]
Months
153. Management algorithm
Antiviral treatment
Treatment failure
Viral load asssessment
Second line therapy
based on cross-resistance data
(Add-on or switch…)
Check compliance Primary non response
Switch to more potent drug
Viral genome sequence analysis
Wild type virus HBV drug resistant mutant
Check compliance
Zoulim and Perrillo, J Hepatol, 2008; EASL CPG J Hepatol 2012
154. Management algorithm
Antiviral treatment
Treatment response
Viral load asssessment
Zoulim and Perrillo, J Hepatol, 2008; EASL CPG J Hepatol 2009
Check for HBe/HBs seroconversion on a
regular basis (6 monthly)
155. Suggested treatment adpatation in patients
with treatment failure
Type of failure Treatment adaptation
Lamivudine resistance 1) add TFV (add ADV if TFV not available)
2) a switch to TFV is also advised by some guidelines
Adefovir resistance 1) switch to TFV (if available) and a 2nd drug
2) if no history of LMV, switching to ETV is also effective.
3) If rtN236T substitution, consider adding LMV, ETV, or LdT to the TFV
or switch to TFV plus FTC
4) If rtA181V/T substitution, alone or in combination with rtN236T, switch
to TFV plus ETV
Telbivudine resistance 1) add TFV
2) a switch to TFV has been considered in some guidelines
3) a switch to ADV is not recommended
Entecavir resistance add TFV
Tenofovir resistance 1) not been confirmed so far
2) genotyping and phenotyping required
3) may add ETV
EASL CPG, J Hepatol 2009 & 2012; Zoulim & Locarnini Liver Int 2013
156. Perspectives beyond the guidelines
• Early treatment intervention to prevent disease progression ?
screening program
non invasive evaluation of liver disease / biomarkers
• Can we prevent prevent HCC development ?
decreased risk of HCC if HBsg clearance <50 yrs (Yuen et al, Gastroenterology 2008)
• Can we clear cccDNA and/or HBsAg ?
new treatment strategies
new treatment targets
157. HBsAg clearance
Werle-Lapostolle B et al., Gastroenterology 2004;126: 1750-58.
Infected hepatocytes
Infected
liver
CD8
NKT
CD4
B
cccDNA
Antivirals
Clearance of
HBsAg?
Blood circulation
viral load
159. Cumulative Probability of HBsAg
Loss During TDF AdministrationCumulativeProbabilityFunctionEstimate
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0.11
0.12
Weeks on Study
0 12 24 36 48 64 80 96 108 120 132 144 156 168 180 192
10.8%
8.5%
• TDF-TDF
• ADV-TDF
Switch to Open Label TDF
Cumulative probability of seroconversion to anti-HBs: 7.7% TDF-TDF
7.3% ADV-TDF
*Kaplan-MeierHeathcote E-J, et al., AASLD 2010; Poster #477.
• TDF-TDF
• ADV-TDF
0 12 24 36 48 64 80 96 108 120 132 144 156 168 180 192
Weeks
CumulativeProbabilityFunctionEstimate
0.12
0.11
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
160. Percentage of
TDF-TDF Patients with HBsAg Loss
Key Characteristic
HBsAg Clearance by Year 4
n/N (%)
Genotype A or D 14/95 (15%)
HBV DNA ≥ 9 log10 copies/mL 12/75 (16%)
HBsAg ≥ 4.5 log10 IU/mL 14/90 (16%)
Knodell Necroinflammatory Score ≥ 9 13/114 (11%)
Heathcote E-J, et al., AASLD 2010; Poster #477.
No HBsAg loss in : Asian patients
HBeAg negative patients
Genotype B or C
161. High rate of HBsAg clearance among sustained
responders to PEG-IFN-2a ± LAM
Marcellin et al. APASL 2009
* Modified ITT analysis (missing = non response);
§ last observation carried forward
5 years post-treatment with PEG-IFN-2a ± LAM (N=230)
<10,000 cp/mL* <400 cp/mL* Cleared HBsAg§
Patients
(%)
21%
17%
12%
64%
0
5
10
15
20
25
30
162. Mason, W. S. et al. 2009 / 2010. J. Virol
Devons nous redéfinir la tolérance immunitaire et
repenser les indications thérapeutiques ?
Observation d’une expansion clonale des
hépatocytes
- Cellules qui n’expriment pas les antigènes
viraux
- Diminution de la charge virale malgré
l’absence de lésion hépatique mesurable
- L’une des premières étapes du CHC
Tolérance Immunitaire
- Presque tous les hepatocytes sont infectés
- Viremies > 10E9 copies/mL
- Devrions nous réaliser une biopsie lorsque
la charge virale diminue sans élévation des
ALAT ? Et penser à un traitement antiviral
?
Zoulim & Mason, W. S. Gut 2012
163. Why a need for new antiviral targets ?
• Current antivirals achieve viral suppression in the
majority of patients
• But the rate of cccDNA / HBsAg loss is very low
• Life-long therapy needed
• HBsAg clearance is associated with a lower risk of
HCC development
• Treatment with finite duration if:
– cccDNA control or loss
– HBsAg loss
Zoulim, Antiviral Research 2012
164. Current treatment: sustained disease control achieved
with NUCs/IFN in majority of patients
Entecavir1,2 Tenofovir3 PEG-IFN α-2a4,5
HBeAg positive n = 354 n = 176 n = 271
HBV DNA undetectable 67% 76% 25%a
HBeAg seroconversion 21% 21% 27%
ALT normalisation 68% 68% 39%
HBsAg loss 2% 3.2% 2.9%b
HBeAg negative n = 325 n = 250 n = 177
HBV DNA undetectable 90% 93% 63%a
ALT normalisation 78% 76% 38%
HBsAg loss 0.3% 0% 0.6%b
1. Chang T-T, et al. N Engl J Med 2006;354:1001–10.
2. Lai C-L, et al. N Engl J Med 2006;354:1011–20.
3. Marcellin P, et al. N Engl J Med 2008;359:2442–55.
4. Lau GKK, et al. N Engl J Med 2005;352:2682–95.
5. Marcellin P, et al. N Engl J Med 2004;351:1206–17.
Results at 48 weeks
a HBV DNA < 400 copies/mL; b At 72 weeks
ALT, alanine aminotransferase; INF, interferon; NUCs, nucleos(t)ide analogues; PEG-INF, peginterferon α-2a;
165. Evolution of viral markers during NUC therapy
Wong et al, Clin Gastroenterol Hepatol 2013
169. Antiviral activity of a TLR7 agonist
in HBV infected chimpanzees
Lanford et al, Gastroenterology 2013
170. Effective T-cells control virus Exhausted T-cells lose control of virus
CD8 T cells
Infected hepatocytes Infected hepatocytes
INF-g
TNF-
IL-2
Granzyme
Perforin
Specific immunomodulation of existing T-cells e.g. PD-1 blockade1,2
Patients who have resolved HBV Patients with chronic HBV
Restoration of defective T-cell
immune control
1. Fisicaro P, et al. Gastroenterology 2010;138:682–93. 2. Fisicaro P, et al. Gastroenterology 2012;143:1576–85
Figure adapted from Nebbia G, et al. Q J Med 2012;105:109–13 and Freeman G, et.al. J Exp Med 2006;203(10):2223–7.
172. The concept of combination therapy
Entry inhibition
cccDNA
- formation
- stability / destruction
- epigenetic regulation
Viral core functions
Other viral targets
Stimulating innate responses
Specific ligands
Stimulating adpative responses
Co-inhibitory signals
Co-stimulatory signals
Therapeutic vaccination
Functional cure / control
Real cure ?
Viral targets Immune modulation
173. Conclusions 1
• Maladie fréquente et grave
– 300 000 porteurs chroniques en france
– 1ère cause de cancer du foie dans le monde
– 1300 décès par an en France
• Maladie méconnue
– Souvent asymptomatique, ou symptomes non spécifiques
– Seulement 60 000 personnes connaissent leur maladie
– 15 000 sont traitées
• Persistance virale
– Pas d’éradication du génome viral
– Surveillance prolongée, possibilité de réactivations
174. Conclusions 2
• Différentes formes d’hépatites en fonction de
l’interaction virus / réponse immunitaire
– Portage asymptomatique / hépatite chronique / cirrhose /
cancer du foie
• Impact de la variabilité du génome viral
- Role dans la persistance virale et la résistance aux antiviraux
- Echappement diagnostique
• Nécessité d’un dépistage et traitement précoce des
formes chroniques
• Prévention par la vaccination !!!
175. Acknowledgements
Hepatology Unit INSERM U1052 Collaborations
David Durantel
Barbara Testoni
Malika Ait-Goughoulte
Souphalone Luangsay
Marion Gruffaz
Nathalie Isorce
Fanny Lebossé
Maelenn Fournier
Julie Lucifora
Maud Michelet
Judith Fresquet
LabEx
C. Caux, Lyon CRCL
U. Hasan, Lyon CIRI
T. Henry, Lyon CIRI
FL. Cosset, Lyon CIRI
M. Levrero, Rome
M. Tommasino, IARC
IHU
176. Potential risk of transmission of HBV DR mutants
Clements et al, Bull WHO 2009
182. Very Early Add-on Therapy to Keep Viral
Load as Low as Possible
2
3
4
5
6
7
8
M0 M3 M6 M9 M12 M15 M18 M21 M24
SerumHBVDNA(Log10copies/mL)
Drug A
Drug A
+
Drug B
Month of therapy
1. Start with a drug having a high genetic barrier for resistance
2. Add a drug with a different cross-resistance profile
outgrowth of drug resistant mutant ?
MDR ?
183. RANDOMIZATION1:1
Tenofovir DF 300 mg
(TDF)
FTC 200 mg / Tenofovir
DF 300 mg
(FTC/TDF)
Study 106: TDF Versus FTC/TDF for Treatment of CHB
in Patients with Persistent Viral Replication Receiving ADV
Double Blind
End of Study
Week 24*
Blinded TDF
or
OL FTC/TDF
Blinded FTC/TDF
or
OL FTC/TDF
Final Study Results
(AASLD 2010)
‡
Berg T, et al., AASLD 2010; Oral# 136.
Week 48 Week 96
*From Week 24 on, patients with confirmed (within 4 weeks) plasma HBV DNA 69 IU/mL had the option to add FTC (as fixed dose
FTC/TDF) or discontinue from the trial and initiate commercially available therapy
Week 168
Blinded TDF
or
OL FTC/TDF
Blinded TDF
or
OL FTC/TDF
Blinded FTC/TDF
or
OL FTC/TDF
Blinded FTC/TDF
or
OL FTC/TDF
* From Week 24 on, patients with confirmed HBV DNA 400 copies/mL (69 IU/mL) could switch to
open label (OL) FTC/TDF or discontinue from the trial and initiate commercially available therapy
Study 106 – Treatment-Experienced Patients
184. P
e
r
c
en
t
age
(
%
)
0
10
20
30
40
50
60
70
80
90
100
Weeks on Study
0 4 8 12 24 36 48 60 72 84 96 108 120 132 144 156 168
Treatment
TDF
FTC/TDF
P
e
r
c
en
t
age
(
%
)
0
10
20
30
40
50
60
70
80
90
100
Weeks on Study
0 4 8 12 24 36 48 60 72 84 96 108 120 132 144 156 168
P
e
r
c
en
t
age
(
%
)
0
10
20
30
40
50
60
70
80
90
100
Weeks on Study
0 4 8 12 24 36 48 60 72 84 96 108 120 132 144 156 168
Treatment
TDF
F
Treatment
TDF
FTC/TDF
Primary Efficacy Analysis:
Comparison of the Two Treatment Strategies
82% FTC/TDF
82% TDF
ITT: NC=F*
Two patients on study at Week 168 had HBV DNA ≥400 copies/mL
‡
Berg T, et al., AASLD 2010; Oral# 136.
Percentage(%)
*NC=F, Non-completer counted as failure in this ITT analysis, including patients who switched to open-label FTC/TDF fixed-dose combination
Study 106 – Treatment-Experienced Patients
% of Patients with HBV DNA < 400 copies/mL (69 IU/mL)
185. Virologic response to TDF according to ADV resistance mutations
at baseline - The Australian Experience
Patterson S J et al. Gut 2011;60:247-254