Systematic review: epidemiology and response to direct‐acting antiviral therapy in genotype 6 chronic hepatitis C virus infection

Abstract

Background: Hepatitis C virus (HCV) genotype 6 (GT6) is predominantly encountered in Southeast Asia and data on GT6 response to direct-acting antiviral (DAA) therapy are relatively limited. Aim:To review the epidemiology and virologic outcome of DAA regimens in HCV GT6 patients. Methods: Electronic literature search of PubMed, EMBASE, and The CochraneLibrary databases were conducted.Results: Hepatitis C virus genotype 6 is the most genetically diverse, has a prevalence of 19.9%-95.6% in HCV infected patients in Southeast Asia and has been associated with a higher risk of HCC in those with cirrhosis. After an extensive literature review, a total of 20 studies were selected to assess study population and treatment outcomes (total of 938 GT6 patients were included); 12 were clinical trials and eight were observational studies. Sustained virologic response at week 12 (SVR 12) following glecaprevir/pibrentasvir (n = 4; 108 patients), ledipasvir/sofosbuvir (n = 8; 427 patients), sofosbuvir/velpatasvir with or without voxilaprevir (n = 5; 171 patients), sofosbuvir/daclatasvir (n = 3; 172 patients) and sofosbuvir with ribavirin (n = 3; 60 patients) was 98%-100%, 64%-100%, 100%, 88%-94% and 100%, respectively. Failure was mostly in those with cirrhosis and prior treatment experience. DAA therapy was well tolerated and with a serious adverse event rate of <5%.Conclusions: Hepatitis C virus genotype 6 is genetically diverse and is highly prevalent in Asia. While SVR rates have been high, cirrhosis and prior treatment experience marginally compromise response to DAAs. Large scale and exclusive studies in HCV genotype 6 prevalent areas are needed, while the current evidence suggests that DAAs are highly effective and safe.

High sustained virologic response in genotypes 3 and 6 with generic NS5A inhibitor and sofosbuvir regimens in chronic HCV in myanmar

“…A unique aspect of this study is the large number of patients infected with HCV genotype 6 (n = 166). Since globally, HCV genotypes 1, 2 and 3 are most common, with genotype 1 accounting for 46% of cases, studies with large cohorts of genotype 6 patients are uncommon . However, these data are important because in South‐East Asia, where HCV infection rates are higher than in the Western World, the most common HCV genotypes are 1, 3 and 6 .…”

“…In South‐East Asia in particular, the prevalence of HCV infection is relatively higher than in Western countries . Nearly 2%‐12% of individuals in South‐East Asian countries are infected with HCV, while in Western countries, such as the United States, the rates are considerably lower (1.6%) . In addition, while globally the most common genotypes are 1, 2 and 3, in South‐East Asia genotypes 1, 3 and 6 are most prevalent .…”

“…Chronic hepatitis C viral (HCV) infection is estimated to affect nearly 70 million people worldwide and can cause significant complications including cirrhosis, liver cancer and liver failure . In South‐East Asia in particular, the prevalence of HCV infection is relatively higher than in Western countries . Nearly 2%‐12% of individuals in South‐East Asian countries are infected with HCV, while in Western countries, such as the United States, the rates are considerably lower (1.6%) .…”

Real‐world effectiveness and safety of ledipasvir/sofosbuvir for genotype 6 chronic hepatitis C patients in Taiwan

“…However, the number of enrolled patients was quite small (25 patients). A meta‐analysis of the effectiveness of DAA treatment for GT6 CHC patients revealed a wide variation of SVR rates in patients treated with LDV/SOF treatment . Hence, more real‐world studies must be conducted, especially in Asia, to evaluate the effectiveness of LDV/SOF treatment for CHC patients with GT6 HCV infection.…”

Editorial: should we abandon HCV genotype testing? Maybe

“…Whether this recommendation should be extended to all treatment settings is still a matter of debate. In this scenario, the study by Mettikanont et al is of relevance as it is the first systematic review to address the epidemiology and treatment options for genotype 6 infections. Genotype 6 (GT6) chronic hepatitis C virus infection accounts for less than 5% of the global prevalence of HCV and is particularly rare in western countries.…”