SEARCH: SouthEast Asian Research Collaborative in Hepatitis

Viral hepatitis leads to greater mortality each year than HIV, TB or malaria. It ranks 7th amongst the leading causes of death worldwide. Unusually for an infectious disease, the numbers of deaths are distributed quite evenly between richer and poorer countries.
The challenge of tackling viral hepatitis has not yet been embraced by the global health community in the same way as HIV, TB and malaria which has been supported by the Global Fund which provides funding for treatments in countries otherwise unable to afford them. But more recently, a recognition of the relative importance of viral hepatitis has informed an ambitious WHO strategy launched for 2016-21.The WHO goals are to reduce deaths from viral hepatitis by 10% by 2020 and 65% by 2030. To do this the ambition is to treat 3 million hepatitis C infected individuals by 2020 and 80% of eligible hepatitis C (HCV) infected individuals by 2030 (a global estimate of approximately 60 million individuals in the next 13 years). This will pose a major challenge, particularly to poorer countries with high burdens of infection, where costs of delivering treatment are prohibitive.
Vietnam is ranked 9th amongst countries for deaths caused by viral hepatitis and has one of the highest mortality rates from hepatitis C in the world with an estimated 1 million individuals infected. It is also classifed as low-middle income by the World Bank. Current treatment rates in Vietnam are relatively low and use interferon containing therapies which involve long courses (24-48 weeks) including weekly injections, a high rates of side effects and offer cure rates in the region of 70%. However, there are now newly approved tablet treatment regimens (without interferon) of between 12 and 24 weeks. These courses of interferon-free direct acting antivirals (DAAs) are highly effective, with far fewer side effects. However, they are currently very expensive and these costs are the limiting factor for treatment in both richer and poorer countries at present. In addition, whilst 12 weeks of therapy represents great progress, many patients will struggle to take a full course.
Despite these facts, recommended therapies will overtreat a high proportion of patients, and over 80% of patients are likely to be curable with two thirds of the recommended treatment duration. We lack are robust ways of predicting which patients these are and ensuring cure is achieved for the minimum price, inconvenience and toxicity. The proposed work aims to create a network and run studies to provide the data needed to inform how new treatments are used. This is particularly important in Vietnam as the type of hepatitis C circulating there is only rarely found in Europe and USA where most of the trials have been done to date. Genotype 6 hepatitis C, the most common genotype in Vietnam, has rarely been included in studies to date and may well differ in its responses to treatment compared to other genotypes.

Novel interferon free treatments for hepatitis C have the potential to cure hepatitis C (HCV) and substantially reduce the resulting mortality from liver cancer and end stage liver disease. The WHO has set ambitious targets to treat 80% of those with active infection (over 70 million people) by 2030. However, access to new treatments is very limited , particularly by price. Vietnam (a low middle income country) has the 9th highest number of deaths attributed to viral hepatitis. An estimated 1 million people are infected with HCV in Vietnam, where the epidemic in Vietnam is unusually characterised by a prevalent circulating viral genotype (6), only seen at high levels in SE Asia.
The proposed work will study a new interferon free treatment combination, sofosbuvir (NS5B inhibitor) and ravidasvir (NS5a inhibitor). The optimum duration of therapy for sofosbuvir/ravidasvir is not known and there is very little data with this or any treatment combination in genotype 6 HCV infection (the only Phase III study completed was done in genotype 4 infection). It is likely that many patients can be cured with treatments shorter than the licensed durations, with the potential to significantly reduce treatment costs and complexity of care.
The work proposed will carry out two studies to evaluate the optimum duration of therapy (i) 60 patients (30 genotype 1, 30 genotype 6). Those whose virus is undetectable (<500 IU/ml) within 48 hours of starting treatment will receive 4 weeks of treatment; others will receive 6 weeks of therapy. All those failing treatment will receive 12 weeks of therapy (ii) in 43 cirrhotics with genotype 6 , patients achieving undetectable (<500 IU/ml) virus in blood at 2 weeks will received 12 weeks, all others 24 weeks. The studies will include full genome sequencing of isolates, pharmacokinetic studies of interactions in HIV drugs and collection of health economic data to inform clinical practice and policy in the scale up of the novel therapies

Viral hepatitis leads to greater mortality each year than HIV, TB or malaria. It ranks 7th amongst the leading causes of death (Stanaway et al 2016). Unusually for a communicable disease, the burden of both mortality and morbidity is quite evenly distributed between high/upper-middle and low/lower-middle income countries (LMICs) (Stanaway et al 2016).

The challenge of tackling viral hepatitis has not yet been embraced by the global health community to the same extent as HIV, TB and malaria which are supported by the Global Fund. However, a increasing recognition of the relative importance of viral hepatitis has given impetus to global initiatives with an ambitious WHO strategy launched for 2016-21 and inclusion of viral hepatitis in the Sustainable Development goals (SDGs).

Rising mortality from hepatitis C is the greatest driver to the increase in mortality from viral hepatitis. East Asia is by far the most heavily affected region with an estimated 460 million attributed deaths each year. The WHO goals are to reduce mortality from viral hepatitis by 10% by 2020 and 65% by 2030. To do this, the ambition is to treat 3 million hepatitis C (HCV) infected individuals by 2020 and 80% of infected individuals by 2030 (a global estimate of approximately 70 million individuals in the next 13 years). Successful cure of HCV has been shown through many studies to significantly reduce the incidence of liver cancer, end stage liver disease (cirrhosis) and all-cause mortality (e.g. Simmons et al 2016).

Vietnam is ranked 9th in counties with deaths attributable to viral hepatitis and has one of the highest mortality rates from hepatitis C in the world (Gower 2014). Current treatment coverage is relatively low with the challenge of delivering interferon based treatments a major obstacle to providing successful therapy. New interferon free therapies have the potential to revolutionise the approach to HCV but are currently beyond the reach of many healthcare systems, particularly in low middle income countries (LMIC).

Meeting the challenges laid set by the WHO Strategy will rely on a range of approaches tackling market access and generic competition, but also in ensuring that (when treatment is purchased by the tablet) that individual patients only have the treatment they need to be cured. This is the aim of this work, to ensure that patients are able to be cured with the minimum amount of treatment they require. Approved treatment regimens of between 12 and 24 weeks of interferon free direct acting antivirals (DAAs) will overtreat a high proportion of patients, and over 80% of patients are likely to be curable with two thirds of the recommended treatment duration. What we lack are robust ways of predicting which patients these are and ensuring cure is achieved for the minimum price, inconvenience and toxicity. in addition to clinical outcomes, real world data and the economic burden of disease (both to the health system and to the patients) will play an important part in developing a policy capable of achieving substantially increased treatment coverage goals.

This programme of work will provide evidence to inform the scale up of treatment and develop the capacity for further, larger studies which will use both novel trial designs (MAMS) and state-of-the-art next generation sequencing technologies to develop algorithms for the management of hepatitis C in Vietnam (which need not involve complex infrastructure and support). The investigators aim to have data to inform the more cost-effective use of expensive medications by 2022. This is particularly important for Vietnam where the most prevalent viral genotype (6) has not been well studied in previous trials.