DISEASE-SPECIFIC CANCER CONTROL
100 CANCER CONTROL 2015
the effectiveness of interventions, to provide a framework
for guiding public health interventions. Although this
research is arguably even more crucial in resource-poor
settings, where health-care budgets are severely limited and
burden of disease is high, previous economic models of HBV
treatment have been limited to high-income and Asian
settings or specific to targeted screening of high-risk groups
only.
One of the barriers to universal implementation of
screening and treatment for hepatitis B has historically been
the cost associated with delivering such an intervention.
However, the major progress in price reduction of antiviral
therapy including tenofovir, which is now available at a
generic price of US$ 48 per year of treatment, has made this
a more feasible strategy in low-middle income countries
(Source: http://www.msfaccess.org/content/untanglingweb-antiretroviral-price-reductions-16th-edition;
accessed
12 December 2014). Within PROLIFICA, community based
screening for hepatitis B has also been shown to be cheap
(£6.47/ per person screened) (30) and cheaper alternative
methods of assessing liver fibrosis have been compared to
the current gold standard of liver biopsy (25). Further
models evaluating cost-effectiveness of screening and
treatment in terms of cost per life year saved are being
developed in collaboration with Imperial College London
(Department of Infectious Disease Epidemiology). This
research will be of utmost importance in informing
international hepatitis guidelines by WHO, as well as in
helping local health ministries prioritize implementation of
screening and treatment of HBV, in places where it poses a
significant health care burden.
Virological determinants in HBV infection
PROLIFICA has provided a unique opportunity for research
on HBV genotype E, which is the dominant species in West
Africa. Next generation sequencing has allowed
investigation of novel associations between the viral
genome and clinical disease. Development of cheaper,
efficient in-house assays to guide clinical management and
investigation of new technologies and biomarkers of
virological activity are also being investigated within the
PROLIFICA platform.
Development of novel point-of-care tests and noninvasive
tests for HBV diagnosis and management
A requirement of the EU grant was developing a research
collaboration with a small-sized commercial partner.
Partnership with commercial diagnostics company Xeptagen
has fast-tracked development of point-of-care tests for HBV
Epidemiology and natural history of HBV infection
and HBV-related liver disease
The PROLIFICA study will provide accurate HBV infection
prevalence data for regions within The Gambia and Senegal,
as well as data on risk factors for HBsAg positivity. Important
data on vaccination coverage will also be provided. The
PROLIFICA study also represents the first large-scale study
describing the prevalence and magnitude of HBV-related
liver disease and incidence of cirrhosis and HCC in SSA,
obtained through comprehensive liver assessment of people
identified as HBsAg positive at screening. Risk factors for
HCC and its predictors will also be examined: of these, mode
of HBV transmission was suggested to be associated with
prolonged hepatitis B e antigenaemia in The Gambia (2). The
symptoms and end-of-life issues in HBV-related chronic liver
disease have been also described (29).
Implementation of HBV screening, liver assessment
and treatment
A key-aim of the study is to demonstrate that both
community and facility-based screening for HBV infection
and assessment of HBV-related liver disease is achievable
and beneficial for improving health in West Africa. Data for
the effectiveness of HBV screening and liver disease
management in the African context are lacking and this
information is crucial to inform government health policymakers.
The project has also provided data to inform
strategies to improve HBV screening uptake and medical
follow-up within West African countries (27). Importantly,
our data to date have shown excellent uptake of HBV
screening and generally high attendance to medical clinics
by patients diagnosed with HBV infection, albeit within the
setting of a clinical trial (28).
Effectiveness of nucleoside analogue therapy for
improving HBV-related outcomes
Tenofovir therapy is widely established as an effective drug
with a high barrier to resistance for the treatment of HBV
infection (1, 31). However, studies have not been conducted
specifically within the African context, particularly
examining safety and effectiveness in African populations.
Data from PROLIFICA will therefore be critical to inform
local ministries of health and government health policy
developers and economists in Africa, as well as the World
Health Organization, on the feasibility, effectiveness and
costs of implementing tenofovir therapy in Africa.
Cost-effectiveness of HBV screening and treatment
Economic analyses use information on the costs, as well as