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Tackling hepatitis C
- what PHE modelling shows us
Helen Harris BSc PhD FFPH
LJWG meeting; November 2014
The burden of hepatitis C in England
• Around 160,000 adults with chronic infection
• HCV-related end-stage liver disease and deaths
have increased steadily over the last 15 years
• Around 90% of new infections are amongst
people who inject drugs (PWID)
• Around half of people who inject psychoactive
drugs are thought to be infected, with around 1 in
7 sharing needles/syringes
PHE hepatitis C in the UK –214 report
Tackling hepatitis C – we know the actions
Action areas
• Prevention of new
infections
• Increasing awareness of
infection
• Increasing testing and
diagnosis
• Getting diagnosed
individuals into treatment
and care
Progress
NHS/PH
Outcomes
Mortality from liver disease
Mortality from causes considered
preventable
Mortality from cancer
Mortality from communicable
diseases
Successful completion of drug
treatment
Early diagnosis of cancer
Inequalities
Quality of life for those with longterm conditions
Recovery from ill health
Prevention of premature mortality
Positive experience of care
How do we tackle hep C in PWID?
• Helping people to quit injecting
• Safe injecting for those who continue
• Treat those with chronic infection
Other important groups
- Past PWID
- Those who acquired infection via blood/blood products
- Black and minority ethnic (BME) populations who
have close links to countries with a high prevalence of
HCV infection.
Modelling acknowledgements
Thanks to Ross Harris
Natural history model
*Journal of Hepatology2014, 61: 530–537
Back-calculation model: the basic idea
• Estimate past incidence and numbers progressing
through a natural history model that would give rise to the
observed endpoint data
Ingredients:
• Observed end-point data over time
HES data on ESLD, HCC; ONS HCC mortality
• Progression probabilities
Reported estimates from cohort studies
Result:
• Predicted history of disease-stage structure
• Future predictions of disease burden
Modelling the7predicted impact of treatment
How are we doing..?
• Nearly 10,850 individuals are currently living with HCVrelated cirrhosis or HCC in England
• Modelling predicts that this figure will rise to 13,590 in 2025
if low coverage of current treatments is maintained
Estimated number of
people living with HCVrelated cirrhosis or
decompensated
cirrhosis/HCC in England:
2005-2030 (95% credible
intervals are given in
parentheses)
PHE hepatitis C in the UK –214 report
Hepatitis C in the UK 2014 report
Both increased uptake and new therapies
are needed
*Journal of Hepatology2014, 61: 530–537
Predictions under different treatment scenarios*
Levels of treatment
• Maintaining current levels (3% treated annually*)
• 100% increase over next 10 years
• Scale up to complete coverage over next 10-15 years
Types of treatment
• Standard treatment (peg interferon and ribavirin)
37% SVR for genotype 1 and 70% non-1
Worse for older patients/more advanced disease
• Improved treatments over next 5 years
90% SVR rate, 60% in cirrhotics
Modelling the predicted impact of treatment
*Journal of Hepatology2014, 61: 530–537
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Standard treatment
Improved treatment
2500
2000
1500
1000
500
0
2015 2020 2025 2030 2035 2040
2015 2020 2025 2030 2035 2040
Year
Current levels
100% increase over next 10 years
Rapid complete coverage
Previous treatment only
Modelling the predicted
impact
of treatment
over
next
10-15 years
Findings
• Disease burden is likely to rise in short term
• Increasing treatment levels will mitigate this, but
short-term rises seem inevitable
• Improved treatment will help to make more
immediate impact
Currently those at highest risk of severe disease have low
probability of achieving SVR
• Swift action required as the infected population
approaches advanced disease stage
Modelling indicates greater impact for treating sooner rather
than later
Modelling the12
predicted impact of treatment
Elimination of infection..?
Elimination: “Reduction to zero of the incidence of
infection caused by a specific agent in a defined
geographical area as a result of deliberate efforts;
continued measures to prevent re-establishment of
transmission are required.”
• In theory if the right tools were available, all infectious
diseases would be eliminated.
• In reality there are distinct biological features of organisms
and technical factors of dealing with them that make their
potential for elimination more or less likely
*http://www.cdc.gov/mmwr/preview/mmwrhtml/su48a7.htm
What can be achieved with new therapies?
• Improved outcomes
•
Improved SVRs, particularly in many previously considered hard-totreat groups including genotype 1 infections, those with advanced
diease, older patients, and those who have failed previous treatment.
• Fewer hospitalisations/deaths for ESLD/HCC
•
Being able to treat those in advanced disease states is key (previously
low SVR rates in cirrhotics)
• Widespread uptake
•
Greater patient acceptability and easier to roll out in community
settings (accessibility) as drugs have fewer side effects, shorter
courses and are easier to administer (all-oral, interferon free)
• Reductions in prevalence
• Stemming transmission
Challenges…
• No vaccine.
• New therapies may be cost
effective but are expensive.
• Hep C treatment services
need to be re-structured country-wide so they are accessible
to all those who need them.
• Asymptomatic nature means large numbers are undiagnosed:
increased awareness, testing & diagnosis are required.
• Under existing systems, investment in hep C prevention,
diagnosis and treatment services is largely determined locally
and money is tight.
Elimination of infection..?
No, but…
Elimination of hepatitis C- related liver disease as a
serious public health concern in England..?
Yes, but challenging...
Goal 1: Prevent further rises in ESLD/HCC,
leading to falling numbers
• New therapies must be made available immediately to anyone
presenting with HCV-related cirrhosis
• Modelling work indicates prevalence of HCV-related cirrhosis is
approaching 11,000 individuals and rising*
• Need to rapidly scale up to at least 20% of cirrhotics receiving new
treatments annually**
• In other words, around 2000 cirrhotic patients per year treated over
the next 10 years
Note: Numbers approximate – based on achieving more than a doubling in current numbers but not
reaching complete coverage; estimates subject to better quantification of SVR rates in cirrhotics
*
PHE Hepatitis C in the UK - 2014 report
** Harris et al. Journal of Hepatology2014, 61: 530–537
Goal 2: Reduce transmission
• New infections driven primarily by people who inject
drugs (PWID)
• Opiate substitution, needle exchange and harm
reduction programs must continue – but not sufficient
alone
• Target to reduce prevalence of chronic infection in this
group by a quarter (from ~40% to ~30%) over the next
10 years
Goal 2: requirements
• Current rates of treatment vary: 5-20 infected PWID per
1000 annually; need to increase to above 20*
•
Modelling assumes those treated have equal risk of reinfection,
retreatment allowed post re-infection but those failing are not retreated
• Equates to around 2000 active PWID treated per year**
• Decreasing barriers to treatment:
•
Easy access to new all-oral interferon-free therapy
•
Available in community settings
•
Acceptance that treating active PWID is worthwhile
*Martin
2013. HCV treatment rates and sustained viral response among people who inject drugs in seven UK
sites: real world results and modelling of treatment impact. Journal of Viral Hepatitis
**Estimates of the Prevalence of Opiate Use and/or Crack Cocaine Use, 2011/12. National Treatment Agency
Conclusion
Tackle the problem from either end:
reducing incidence and HCV-related morbidity
Important targets with measurable outcomes
and specific goals
Working
towards
Elimination of hepatitis C- related liver disease as a
serious public health concern in England
Acknowledgements
• Ross Harris
• Michael Sweeting
• Dani de Angelis
• Sema Mandal
• Mary Ramsay
• Annastella Costella
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