Neglected Diseases
Hepatitis C is a blood-borne infectious disease caused by the hepatitis C virus (HCV), primarily affecting the liver. HCV causes both acute and chronic infection, with symptoms in the acute phase including fever, fatigue and jaundice. However, up to 80% of acute cases are asymptomatic, meaning that many HCV infections will go undetected until chronic disease develops, sometimes decades later. Although 20-40% of acute infections resolve spontaneously without treatment, the remaining 60-80% of cases will progress to chronic infection.
Without treatment, chronic hepatitis C is a lifelong disease which can lead to life threating liver damage (cirrhosis and fibrosis) and hepatocellular carcinoma (liver cancer).
There are six main genotypes of HCV, with genotypes 4, 5 and 6 disproportionately affect developing countries, while having a low prevalence in high-income countries. Since R&D efforts have moved from genotypic-specific to pan-genetypic products, in the 2019 report we replaced the genotype restriction for inclusion in G-FINDER with more detailed restrictions on LMIC applicability and use.
Direct-acting antiviral (DAA) drugs are more effective, require a shorter duration of treatment, and have fewer side effects than previous interferon- and ribavirin-based treatments, and have revolutionised the treatment of hepatitis C. However, DAA-based regimens are expensive, and access remains limited in LMICs. More research is also needed to assess DAA-based regimens in developing country populations, adolescents, children under 12, and pregnant or breastfeeding women. Despite extensive research efforts, the virus’ genetic diversity and limited infection models have meant that no protective vaccine yet exists, with many candidates not maturing beyond preclinical and early clinical development. A broadly reactive vaccine would prevent incidence of new infections and ideally elicit an antibody and cross-reactive T-cell response. There is also a need for HCV diagnostic tests that are affordable and simple to use in developing country contexts, especially tests for treatment monitoring, screening and tests of cure.
A hepatitis C drug regimen partly developed in Malaysia has been added to the World Health Organization’s essential medicines list (EML): the WHO endorsed the use of ravidasvir in combination with sofosbuvir as a direct-acting antiviral for the treatment of chronic hepatitis C virus infection in adults. The development of ravidasvir was initiated by Malaysia’s health ministry and DNDi, in partnership with Thailand’s health ministry, Médecins Sans Frontières, Presidio Pharmaceuticals, Pharco Pharmaceuticals and Pharmaniaga Berhad.