An Update HBV Treatment · necro-inflammation or fibrosis >2 x ULN irrespective of fibrosis...

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Daryl T.-Y. Lau, MD, MPH

Associate Professor of Medicine

Director of Translational Liver Research

Division of Gastroenterology

BIDMC, Harvard Medical School

Epidemiology

Treatment

An Update HBV Treatment

Natural history

HBV Discovered in Korean Mummy

Dated to the 16th Century AD

• Laparoscopic liver biopsies performed on mummified

Korean child dated to 16th Century A.D.

• Complete sequence of the oldest HBV isolate and the

most ancient full viral genome known so far

• Genome (3,215 base-pairs) analysis of the ancient HBV

revealed a unique HBV genotype C2 (HBV/C2) sequence

commonly spread in Southeast Asia

• Comparison of the ancient genome with contemporary

HBV/C2 DNA sequences from various regions in East

Asia showed significant differences

• Sequence likely dates back to 3,000-100,000 years ago

Bar-Gal G, et al. 63rd AASLD; Boston, MA; November 9-13, 2012; Abst. 927.

Global Burden of Disease Study 2010:

Causes of Death From Chronic Liver Disease

Cowie BC, et al. Hepatology. 2013;58(suppl 1):218A-219A. Abstract 23.

Pa

tie

nts

(%

)

45%

Global 2010

26%

HBV

Liver Cancer

20%

30% 28%

14%

27%

9%

HCV ETOH Other HBV

Cirrhosis

HCV ETOH Other P

atie

nts

(%

)

16%

USA 2010

40%

HBV

Liver Cancer

29%

8%

40%

13%

39%

14%

HCV ETOH Other HBV

Cirrhosis

HCV ETOH Other

Increase in liver-cancer deaths (past 20 years):

Globally (from 1.25 to 1.75 million/year); USA (45,000 to 70,000/year).

Geographic Prevalence of Chronic Hepatitis B Impacted by Migration

World Health Organization. Geographic Prevalence of HBsAg. Data from 1996 (unpublished). http://www.who.int/vaccines-surveillance/graphics/htmls/hepbprev.htm. Accessed: September 13, 2004.

Mahoney FJ. Clin Microbiol Rev. 1999;12:351-366.

HBsAg Prevalence

8% - High

2-7% - Intermediate

<2% - Low

Immigration numbers summed by continent from 1996-2002

~2 million Asians

~400,000

South Americans

~350,000 Africans

~930, 000

Europeans

Estimated HBV Prevalence Among Foreign-Born Americans (2008)

All Foreign

Born (n=41,329,349)

Asia (n=10,970,572)

Foreign-Born Americans:

13.6% of General Population

Welch S, et al. Hepatology. 2008;48(suppl):687A-688A. Abstract 853.

Ch

ron

ic H

BV

Pre

vale

nce (

%)

Central

America (n=16,068,537)

Caribbean (n=3,588,352)

South

America (n=2,856,583)

Africa (n=1,669,101)

Europe (n=5,113,072)

North

America (n=888,318)

3.7%

7.9%

1.3% 2.3%

1.6%

11.8%

2.2%

0.3%

Age at Infection

0

20

40

60

80

100

Neonates Infants Children Adults

%

Risk

Risk of Chronic Infection is Inversely

Related to Age at Infection

Endemic

Regions

HBV : Liver Disease Progression

Acute

Infection

Chronic

infection Cirrhosis Death

Liver

Failure

Liver

Cancer

(HCC)

Liver

Transplantation

>90% of

children

<5% of adults

Phases of Chronic HBV Infection

Normal ALT HBV DNA

>1,000,000 IU/ml

ALT > 2X normal HBV DNA

>10,000 IU/ml

Normal ALT HBV DNA

<1,000 IU/ml

ALT > 2X normal HBV DNA

≥1,000 IU/ml

HBV Genome Organization

Evaluation of the prevalence of PC and BCP mutations

1349 baseline samples in the HBRN Cohort Study from 21 centers in US and

Canada between 2011 and 2013 were included.

Patients on antiviral therapy were excluded.

Hepatitis B Research Network (HBRN)

HBV Patient Populations in North America

D. Lau and HBRN investigators, AASLD 2014, Boston, USA

0

5

10

15

20

25

30

35

40

45

ImmuneTolerant(N=146)

HBeAg+ve CHB(N=203)

InactiveCarriers(N=434)

HBeAg-ve CHB(N=378)

%

HBV Phenotypes

Dual BCP

PC

BCP and PC Mutants Across HBV Phenotypes

D. Lau and HBRN investigators,

AASLD 2014, Boston, USA

Phases of Chronic HBV Infection

Wide type

PrecoreBCP

Liver targeted

Safety profile for

bone and kidneys

Timeline based on FDA approval in the United States

The New Era

Oral Therapy

HBV: Current Treatment Guidelines

Guideline

HBeAg+ HBeAg-

HBV DNA

IU/mL

ALT U/L HBV DNA

IU/mL

ALT U/L

EASL

2017

≥2,000

≥20,000

>ULN and/or at least moderate liver

necro-inflammation or fibrosis

>2 x ULN irrespective of fibrosis

≥2,000

≥20,000

>ULN and/or at least moderate liver

necro-inflammation or fibrosis

ALT >2 x ULN irrespective of fibrosis

AASLD

2018 >20,000

>2x ULN or significant histological disease

>2,000 >2x ULN or

significant histological disease

APASL

2015 ≥20,000

>2x ULN or significant histological disease

≥2,000 >2x ULN or

significant histological disease

REVEAL-HBV Study: 13-Year Cumulative Incidence of Hepatocellular Carcinoma

Chen CJ, et al. JAMA. 2006;295:65-73.

0

2

4

6

8

10

12

14

16

18

20

<300

Cu

mu

lati

ve I

ncid

en

ce (

%)

1.3

300 - <104 104 - <105

All patients (n=3653)

HBeAg negative

Only (n=3088)

Normal ALT (n=2966)

Normal ALT and no cirrhosis (n=2925)

105 - <106 >106

1.2 0.98 0.74 1.37

0.89 1.21 1.25

3.57 3.68 3.42 3.15

12.17

9.54

8.55 7.96

14.89

17.88

19.51

13.50

Baseline HBV DNA (copies/mL)

ALT normalization

Fibrosis regression

HCC reduction but NOT elimination

Ju-Yeon Cho et al. Gut 2014;63:1943-1950

Ju-Yeon Cho et al. Gut 2014;63:1943-1950

Kim et al. Gut 2014

• Further eliminate HCC risk

• No risk of HBV reactivation

However:

• cccDNA: Stable and persists even after

recovery from acute infection

• Very difficult to eliminate integrated HBV DNA

in host genome

AASLD

0

0.02

0.04

0.06

0.08

0.1

0.12

Pro

ba

bili

ty

Weeks on Treatment

Double-Blind Open-Label

TDF to TDF

ADV to TDF

11%

8.5%

23 patients who were HBeAg(+) at baseline and achieved HBsAg loss and 19 had HBsAg seroconversion for up to 240 weeks of tenofovir DF treatment; 2 had reversion back to HBsAg(+) (1 confirmed, 1 not confirmed).

0 24 48 72 96 120 144 168 192 216 240

23 patients who were HBeAg (+) at baseline and achieved HBsAg loss 19 had HBsAg seroconversion for up to 240 weeks of tenofovir DF treatment; 2 had reversion back to HBsAg(+) (1 confirmed, 1 not confirmed).

HBV Replicative Cycle

Papatheodoridis G et al, Hepatology 2016

TIME

Risk of severe flare?

ALT

Nucleos(t)ide Analog (NA)

Lag-phase

(variable

<1-12 months)

HBV DNA

Reactivation phase

( 3 months)

Limit of HBV DNA detection

Consolidation phase

( 12 months)

Treatment phase (> 3 years)

Expected Outcomes

HBeAg(-): Expected Outcomes Post-Therapy

Modified from Lampertico P & Berg T, Hepatology 2018

TIME

Risk of severe flare?

ALT

Nucleos(t)ide Analog (NA)

Lag-phase

(variable

<1-12 months)

HBV DNA

Reactivation phase

( 3 months)

Limit of HBV DNA detection

Consolidation phase

( 12 months)

Treatment phase (> 3 years)

Sustained virologic

response ( 20-30%)

HBsAg (-) after 2-3 years

( 20%)

Indeterminate state not

re-treated

( 10-20%)

Requiring re-treatment

( 40%)

Expected Outcomes

HBeAg(-): Expected Outcomes Post-Therapy

Modified from Lampertico P & Berg T, Hepatology 2018

HBeAg (-): Therapy

Why stop: • Functional cure with HBsAg loss • Response can be sustained or increased off therapy • Cost of therapy • Patients do not desire indefinite therapy

When to stop: • After a period of therapy consolidation???

HBeAg(-): HBsAg loss after NA Cessation

• 1,075 Taiwanese patients treated with ETV or TDF for 156 (61-430)

weeks

• HBsAg loss during therapy: 6 patients (annual incidence of 0.15%)

• 691 patients stopped NA therapy, 308 (45%) had cirrhosis

• 3-year cumulative virologic relapse (79%) and clinical relapse (61%)

• 42 patients achieved HBsAg loss

• 6-year cumulative incidence of HBsAg clearance: 13%, estimated

annual incidence 1.78%

Jeng WJ et al, Hepatology 2018

HBeAg(-): HBsAg loss after NA Cessation

Serious adverse events during follow-up after stopping therapy

• 7 of 308 (2.2%) patients with cirrhosis developed hepatic decompensation

• 3 (~1%) died despite retreatment

Jeng WJ et al, Hepatology 2018

HBeAg (-) Chronic Hepatitis B

Only very selective patients should be considered for discontinuing therapy, ideally in clinical trial setting

At least monthly monitoring is critically important off therapy

Patients with advanced stage 3-4 hepatic fibrosis should NOT discontinue antiviral therapy.

HBeAg (-) Chronic Hepatitis B

Blood

Liver

Many unanswered questions

Predictors of HBsAg loss need to be confirmed

When to restart therapy during relapse

low level HBV DNA replication:

? HCC risk

? Increase cccDNA

? DNA integration

Novel HBV Therapy

HBsAg Release

Inhibitors

NA Taurocholate Co-transporting Polypeptide

The main features of the HBV life cycle and potential antiviral targets

Locarnini, S. & Zoulim, F. et al. (2016) Global strategies are required to cure and eliminate HBV infection Nat. Rev. Gastroenterol. Hepatol. doi:10.1038/nrgastro.2016.7

HBV Entry Inhibitors

Targeting cccDNA

siRNA

HBV Polymerase inhibitors

Capsid Assembly Inhibitors

Immunomodulators

NA Taurocholate Co-transporting Polypeptide

HBsAg Release

Inhibitors

HBsAg levels depend on:

Number of infected hepatocytes

Amount of transcriptionally active cccDNA

Major challenge:

Cannot distinguish transcriptionally active viral integrated sequences

Kimura T et al. JBC 2005; 280: 21713 Wang et al. J Hepatol 2016

Released in serum as enveloped 3.5 kb pregenomic RNA containing virions

Kimura T et al. JBC 2005; 280: 21713 Luckenbaugh L et al. J Viral Hepat 2015; 22: 561

Electrochemilumisescent assay: Lumipulse G (Fujirebio)

Simultenous determination of denatured HBeAg, HBcAg, p22crAg (same 149 amino acids)

ARC-520

Gane et al, AASLD 2018

The future looks bright but with many new challenges

The current nucleos(t)ide analogue therapy is safe and effective

but low rate of functional cure

The novel therapy likely need to be used in combination. Their

efficacy and safety yet to be determined

New treatment endpoints and biomarkers need to be evaluated

Therapeutic options for different HBV populations need to be

determined and standardized