Distribution of hepatitis C virus genotypes among blood donors in Taiwan

Sexually-transmitted hepatitis C virus reinfections among people living with HIV in Taiwan: the emerging role of genotype 6

Hepatitis C virus (HCV) reinfections after successful treatment with direct-acting antivirals (DAAs) pose a significant challenge to HCV elimination, especially among high-risk people living with HIV (PLWH). In this study, PLWH who had achieved HCV viral clearance with DAAs were included between January 2018 and June 2021. PLWH having acquired HCV infections after 2017 were classified as "recent-infection group," and those before 2017 as "remote-infection group," and the incidences of HCV reinfection were compared between two groups. Clinical and behavioural characteristics were evaluated to identify associated factors with HCV reinfection. A total of 284 PLWH were included: 179 in the recent-infection group and 105 in the remote-infection group. After a median follow-up of 2.32 years (interquartile range [IQR], 0.13-3.94), the overall incidence of HCV reinfection was 5.8 per 100 person-years of follow-up (PYFU). The incidence in the recent-infection group was significantly higher than that in the remote-infection group (9.8 vs. 0.4 per 100 PYFU, p < 0.001). The leading HCV genotypes before DAA treatment were genotypes 2 (31.0%), 1b (26.8%), and 6 (21.8%); however, genotype 6 (58.8%) became predominant upon reinfection. Younger age (adjusted odds ratio [aOR] per 1-year increase, 0.95; 95% CI, 0.90-0.99), condomless receptive anal sex (aOR, 14.5; 95% CI, 2.37-88.8), rimming (aOR, 3.87; 95% CI, 1.14-13.1), and recent syphilis (aOR, 2.73; 95% CI, 1.26-5.91) were linked to HCV reinfections. In conclusion, PLWH acquiring HCV after 2017 had a significantly higher risk for sexually-transmitted HCV reinfections. The predominance of HCV genotype 6 reinfections suggests possible on-going clustered HCV infections among at-risk PLWH.

Real-world effectiveness of direct-acting antivirals in people living with human immunodeficiency virus and hepatitis C virus genotype 6 infections

BACKGROUND

Hepatitis C virus (HCV) genotype 6 (HCV-6) infection is prevalent predominantly in Southeast Asia, and the data on the virologic response of HCV-6 to direct-acting antivirals (DAAs) are sparse in people living with human immunodeficiency virus (HIV) (PLWH).

AIM

To assess the virologic response of HCV-6 to DAAs in PLWH.

METHODS

From September 2016 to July 2019, PLWH coinfected with HCV-6 initiating DAAs were included. Laboratory investigations were performed at baseline, the end of treatment, and 12 wk off-therapy.

RESULTS

Of the 349 PLWH included (mean age 48.9 years, 82.5% men), 80.5% comprised people who inject drugs, 18.1% men who have sex with men, and 1.4% heterosexuals. Coexistent hepatitis B virus infection was present in 12.3% of the included PLWH, liver cirrhosis 10.9%, hepatocellular carcinoma 0.9%, and previous HCV treatment experience 10.9%. The mean baseline plasma HCV RNA was 6.2 log₁₀ IU/mL. Treatment with glecaprevir/pibrentasvir was initiated in 51.9%, sofosbuvir/ledipasvir 41.5%, sofosbuvir/velpatasvir 6.3%, and sofosbuvir/daclatasvir 0.3%. At DAA initiation, antiretroviral therapy containing tenofovir alafenamide was given in 26.4%, tenofovir disoproxil fumarate 34.4%, non-tenofovir alafenamide/tenofovir disoproxil fumarate 39.3%, non-nucleoside reverse-transcriptase inhibitors 30.4%, protease inhibitors 4.0%, and integrase strand transfer inhibitors 66.8%; 94.8% of the included patients had CD4 counts ≥ 200 cells/mm³ and 96.0% had plasma HIV RNA < 50 copies/mL. Overall, 96.8% achieved undetectable plasma HCV RNA (< 30 IU/mL) at end of treatment; and 92.3% achieved sustained virologic response 12 wk off-therapy in the intention-to-treat analysis (93.5% in patients receiving sofosbuvir-based DAAs and 91.2% in those receiving glecaprevir/pibrentasvir).

CONCLUSION

Similar to the observation made in HIV-negative patients, sustained virologic response 12 wk off-therapy with DAAs is high in PLWH coinfected with HCV-6.

Ropeginterferon alfa-2b in patients with genotype 1 chronic hepatitis C: Pharmacokinetics, safety, and preliminary efficacy

Background and Aim

Ropeginterferon alfa‐2b (P1101) is a novel long‐acting mono‐PEGylated recombinant proline interferon (IFN) conjugated to a 40 kDa branched polyethylene glycol (PEG) chain at its N‐terminus, allowing every‐two‐week injection. It received European Medicines Agency and Taiwan marketing authorization for the treatment of polycythemia vera in 2019 and 2020, respectively. This phase 2 study aimed to evaluate the pharmacokinetics, safety, and preliminary efficacy of ropeginterferon alfa‐2b as compared with PEG‐IFN‐α2a in patients with chronic hepatitis C virus genotype 1 infection.

Methods

One hundred six treatment naive patients were enrolled in this phase 2 study and randomized to four treatment groups: subcutaneous weekly PEG‐IFN‐α2a 180 μg (group 1), weekly ropeginterferon alfa‐2b 180 μg (group 2), weekly ropeginterferon alfa‐2b 270 μg (group 3), or biweekly ropeginterferon alfa‐2b 450 μg (group 4) plus ribavirin for 48 weeks.

Results

After multiple weekly administration, serum exposure (AUC_0‐τ) in ropeginterferon alfa‐2b 180 μg was approximately 41% greater and the accumulation ratio of 2‐fold greater than PEG‐IFN‐α2a 180 μg. The incidences of flu‐like symptoms were 66.7% (18/27), 53.3% (16/30), 55.0% (11/20), and 48.3% (14/29), anxiety were 14.8% (4/27), 6.7% (2/30), 0%, and 0%, and depression were 25.9% (7/27), 13.3% (4/30), 0%, and 3.4% (1/29), for groups 1–4, respectively. Two grade 2 of 3 depression were noted in PEG‐IFN‐α2a arm, but none in ropeginterferon arms. The SVR24 rates were 77.8% (21/27), 66.7% (20/30), 80% (16/20), and 69% (20/29), respectively.

Conclusions

Ropeginterferon alfa‐2b showed longer effective half‐life and superior safety profile than PEG‐IFN‐α2a. Biweekly injection of ropeginterferon alfa‐2b will be studied in larger viral hepatitis patient population.

Geographic variation of genotype 6 hepatitis C virus infection in an endemic area of southern Taiwan

Taiwan is a hepatitis C virus (HCV) endemic country with geographic variation of prevalence and main genotypes(GTs) are 1 b and 2a. We recently reported high GT6 prevalence in Tainan of southern Taiwan. To clarify this special genotype as a local endemic disease and its geographic variation, the prevalence rates of HCV GTs of 37 districts of Tainan were analyzed. A total of 3040 patients with HCV viremia were enrolled. The prevalence rates of HCV GT 1a, 1 b, 2, 3, 4, 6 and mixed types were 3.9%, 31.6%, 45.9%, 0.6%, 0.2%, 17.1% and 0.5% respectively. GT6 prevalence showed marked variation from 0 to 39.2%. Four districts with GT6 prevalence >30% are located between Jishui and Zengwen rivers. Preliminary subtyping data were 6 g/a/w. This geographic variation with spatial restriction by two rivers with 6 g/w is suggestive of local endemic infection of preexisting GT 6 HCV for centuries.

High prevalence of genotype 6 hepatitis C virus infection in Southern Taiwan using Abbott genotype assays

BACKGROUND/PURPOSE

Abbott RealTime Genotype II assay can effectively identify hepatitis C virus (HCV) genotypes (GTs), but some GT 6 subtypes might not be differentiated from GT 1. Abbott RealTime Genotype II PLUS and sequencing might be needed to resolve these ambiguous results. Unlike the high prevalence of GT 6 in Southeast Asia, GT 6 had rarely been reported in Taiwan except in intravenous drug abusers (IDU). But the prevalence of GT 6 in Taiwan might be underestimated. We conducted this study to determine the GTs in a HCV endemic area in Southern Taiwan.

METHODS

A total of 1147 patients with hepatitis C viremia for direct acting antivirals (DAA) treatment at the Chi Mei medical system in Tainan were enrolled. Genotype was determined using a working flow consisted of Abbott GT II, PLUS assays and 5' untranslated region (5' UTR)/core sequencing.

RESULTS

Among the 1147 patients, 883 (77.0%) obtained GT results by GT II, 264 (23.0%) samples with ambiguous results by GT II assay received further tests, including 194 (73.5%) with PLUS assay and 70 (26.5%) with 5'UTR/core sequencing. Nearly three-quarters (73.5%) of ambiguous results by GT II assay were GT 6. Overall, 18.3% of samples were GT 6. Phylogenetic study of 11 samples of GT 6 subtypes showed 7 (63.6%) were 6 g.

CONCLUSION

GT 6 is the major factor for high ambiguous rate by GT II. Unexpected high prevalence of GT 6 (18.3%) in Southern Taiwan, especially subtype 6 g, closely related to Indonesian strains, is first reported.

Molecular epidemiology of HIV-1 infection in Taiwan from 2005 to 2008: further spread of CRF07_BC and emergence of CRF07_BC/subtype B dual infection

BACKGROUND

In 2004, HIV-1 infection among Taiwanese injection drug users (IDUs) started to surge. In 2007, a resurgence of HIV-1 epidemic among men having sex with men (MSM) occurred. We conducted a molecular epidemiological study of HIV-1 among different risk groups in Taiwan from 2005 to 2008.

METHODS

In total 1133 HIV-1-infected adults including 576 IDUs, 464 MSM, and 93 heterosexuals were recruited. HIV-1 subtypes were determined using nested multiplex polymerase chain reaction and phylogenetic analysis. Dual infection was confirmed using cloning, sequencing, and heteroduplex mobility assay.

RESULTS

Among HIV-1/AIDS subjects, 96.1% MSM and 62.5% heterosexual males were infected with subtype B, whereas 66.7% female heterosexuals were infected with CRF01_AE. Most IDUs (84.5%) were infected with CRF07_BC. Four heterosexual males, 2 females and 2 MSM who were not IDUs had CRF07_BC. Forty-nine patients had CRF07_BC/subtype B dual infection and 44 (89.8%) were IDUs. Multivariate logistic regression showed that the odds ratio for dual infection among IDUs who shared syringes >5 times per month was 4.7 (95% confidence interval = 1.3 to 17.7). Phylogenetic analyses revealed that there were 2 main groups of CRF07_BC strains with sporadic transmission between different risk groups. Among 10 IDUs infected with CRF01_AE, 7 cases were clustered with an outbreak happened in 2005 and 3 cases were clustered with other strains from heterosexual population.

CONCLUSIONS

In Taiwan, 7.8% of HIV-1-infected IDUs had dual infection. It may have important impact to their clinical management. Although CRF07_BC was still remained in IDUs, it has spread to MSM and heterosexual populations.

Hepatitis C virus seromarkers and subsequent risk of hepatocellular carcinoma: long-term predictors from a community-based cohort study

PURPOSE

Hepatitis C virus (HCV) contributes to one third of hepatocellular carcinoma cases worldwide. Long-term predictors for HCV-related hepatocellular carcinoma are essential for early intervention. Serum HCV RNA and ALT levels and HCV genotype were assessed for their predictability of hepatocellular carcinoma risk.

METHODS

A prospective cohort of 925 participants positive for antibodies against HCV and age 30 to 65 years was recruited and followed from 1991 to 2006. Serum HCV RNA and ALT levels and HCV genotypes at enrollment and during follow-up were examined. Newly developed hepatocellular carcinoma was identified by health examination and computerized linkage with national cancer registration and death certification profiles. Multivariate adjusted hazard ratios with 95% CIs were estimated using Cox regression models.

RESULTS

Fifty-five participants newly developed hepatocellular carcinoma during 8,476 person-years of follow-up, giving an incidence rate of 648.9 per 100,000 person-years. The cumulative hepatocellular carcinoma risk increased from 1.1% for HCV RNA seronegative status to 6.4% for low HCV RNA levels and to 14.7% for high HCV RNA levels (P < .001). The cumulative risk also increased with elevated serum ALT levels from 1.7% for persistently ≤ 15 U/L to 4.2% for ever more than 15 U/L but never more than 45 U/L and to 13.8% for ALT ever ≥ 45 U/L (P < .001). Having HCV genotype 1 was associated with a higher cumulative hepatocellular carcinoma risk (12.6%) than not having HCV genotype 1 (4.5%; P < .001).

CONCLUSION

Elevated serum levels of HCV RNA and ALT and HCV genotype 1 infection are independent risk predictors of hepatocellular carcinoma. These findings have strong implications for the management of chronic HCV.

Molecular epidemiology of HCV genotypes among injection drug users in Taiwan: Full-length sequences of two new subtype 6w strains and a recombinant form_2b6w

Human immunodeficiency virus type 1 (HIV-1) circulating recombinant form (CRF) 07_BC strain has caused serious outbreaks among injection drug users in Taiwan since 2004. The objective of this study was to conduct a molecular epidemiological study of HCV genotypes in intravenous drug users in Taiwan. Blood samples and questionnaires from 591 intravenous drug users infected with HIV-1 were collected nationwide. In total, 180 samples were selected for HCV genotyping using multiplex PCR and phylogenetic analysis of the core, E1 and NS5B regions. The Inno-Lipa assay was used to confirm multiple infections with different genotypes. Eighty percent had a single infection with subtype 1b being the most common subtype (24%), 12% had double infections and two had triple infections. In addition, three recombinant forms (RFs)-2a1a, 3a1b, and 2b6w were identified. Phylogenetic analyses showed that the 3a, 6a, and 6n strains were clustered with strains present in Thailand and mainland China. Full-length sequence analysis showed that two 6w strains shared 89.4-90.2% sequence homology with the 6(r) strain from the Guangdong Province, China. Bootscan analysis revealed that the recombination breakpoint of RF_2b6w was located at the NS2-NS3 junction. In summary, the distribution of HCV genotypes among Taiwanese intravenous drug users was complex and more than 12% of the drug users were infected with more than one genotype of HCV.

Molecular and contextual markers of hepatitis C virus and drug abuse

The spread of hepatitis C virus (HCV) infection involves a complex interplay of social risks, and molecular factors of both virus and host. Injection drug abuse is the most powerful risk factor for HCV infection, followed by sexual transmission and additional non-injection drug abuse factors such as co-infection with other viruses and barriers to treatment. It is clearly important to understand the wider context in which the factors related to HCV infection occur. This understanding is required for a comprehensive approach leading to the successful prevention, diagnosis, and treatment of HCV. An additional consideration is that current treatments and advanced molecular methods are generally unavailable to socially disadvantaged patients. Thus, the recognition of behavioral/social, viral, and host factors as components of an integrated approach to HCV is important to help this vulnerable group. Equally important, this approach is key to the development of personalized patient treatment - a significant goal in global healthcare. In this review, we discuss recent findings concerning the impact of drug abuse, epidemiology, social behavior, virology, immunopathology, and genetics on HCV infection and the course of disease.

Cost-utility analysis of different peg-interferon alpha-2b plus ribavirin treatment strategies as initial therapy for naïve Chinese patients with chronic hepatitis C

BACKGROUND

Different peg-interferon alpha-2b plus ribavirin treatment strategies are more effective in treating hepatitis C. However, no cost-effectiveness data have been published using the clinical data from the peg-interferon alpha-2b and ribavirin in the treatment of patients with hepatitis C in Taiwan.

AIM

To estimate the cost-effectiveness of different treatments with peg-interferon alpha-2b plus ribavirin for the initial treatment of patients with different genotype chronic hepatitis C.

METHODS

Individual patient level data from a randomized clinical trial with peg-interferon plus ribavirin were applied to a Markov model to project lifelong clinical outcomes. Economic estimates and quality of life were based on published data and Taiwan patient data. We used a societal perspective and applied a 3% annual discount rate.

RESULTS

Compared with different combination therapy strategies, peg-interferon alpha-2b plus weight-based dosing of ribavirin in all patients for 24 weeks is the most cost-effective treatment strategy. If the sustained virological response of peg-interferon plus ribavirin treatment for 48 weeks therapy in genotype 1 patients was higher than 67.8%, the best strategy of treating patients will be the peg-interferon plus weight-based dosing of ribavirin therapy for 48 weeks in genotype 1 patients and for 24 weeks in non-genotype 1 patients.

CONCLUSIONS

Peg-interferon alpha-2b plus ribavirin combination for 24 weeks therapy in all genotype patients should reduce the incidence of liver complications, prolong life, improve quality of life and be cost-effective for the initial treatment of chronic hepatitis C.

Clinical aspects and outcomes of volunteer blood donors testing positive for hepatitis-C virus infection in Taiwan: a prospective study

BACKGROUND/AIM

The natural history of hepatitis-C virus (HCV) infection has been explored in volunteer blood donors, but not yet in hepatitis-B endemic areas. Whether previous or concurrent hepatitis-B virus (HBV) infection influences the natural history of HCV infection remains unknown. Thus, we followed the anti-HCV-positive blood donors who had past or concurrent HBV infection in Taiwan.

METHODS

From 1992 to 1993, 1588 anti-HCV reactive volunteer blood donors were referred to us from the Taipei Blood Center and 879 (55%) repeatedly reactive for anti-HCV were enrolled. Two hundred and forty-three donors (HCV RNA seropositive rate 49% by polymerase chain reaction (PCR)) received regular follow-ups (mean period: 4.9 years) with their liver disease status determined mainly by clinical and biochemical parameters, serum alpha-fetoprotein level and imaging studies. Hepatitis-C virus genotype and occult HBV infection were determined by PCR-based assays.

RESULTS

Of the initial 879 subjects, 250 (28%) had chronic hepatitis, nine (1%) had liver cirrhosis (LC) and two (0.2%) had hepatocellular carcinoma (HCC) already. In the 243 regularly followed donors, 30% had repeatedly normal serum alanine aminotransferase (ALT) and 70% had more than once elevated ALT. Cirrhosis developed in four (1.6%; follow-up period range: 2-6 years) and HCC in two (0.8%; follow-up period: 3 and 4 years, respectively). Distribution of HCV genotype and hepatitis-B surface antigen (HBsAg) did not differ between those with and those without elevation of ALT. Of the 15 donors with LC and/or HCC, only 1(7%) was positive for both HBsAg and HBV DNA and the other 14 were negative for both HBsAg and serum HBV DNA.

CONCLUSIONS

Incidentally detected hepatitis-C was progressive in a small proportion of anti-HCV-positive volunteer blood donors in Taiwan. Occult HBV infection played a minimal role in the development of LC in this donor population.

Hepatitis C virus genetic variability: pathogenic and clinical implications

HCV is variable because of the properties of the viral RdRp, high levels of replication, and large population sizes. The Darwinian evolution of HCV has been characterized by the emergence of the HCV genotypes, including six main types and a large number of subtypes. The study of HCV genotype epidemiology provides useful information on the worldwide HCV epidemics. The HCV genotype is an important predictor of the response to IFN-alpha-based antiviral therapy, and genotype determination is currently used to tailor treatment indications. In addition, HCV circulates and behaves in infected individuals as mixtures of closely related but distinct viral populations referred to as quasispecies. This particular nature of the virus influences its transmission, the pathogenesis of liver disease and extra-hepatic manifestations, and the outcome during and after antiviral therapy or after transplantation for HCV-related end-stage liver disease. Further studies are needed to understand better the implications of HCV quasispecies diversity in the pathophysiology of HCV infection.

Changing prevalence of hepatitis C virus genotypes: molecular epidemiology and clinical implications in the hepatitis C virus hyperendemic areas and a tertiary referral center in Taiwan

To determine the hepatitis C virus (HCV) genotype distribution in Taiwan and to clarify the relationship between genotype and the pathogenesis of HCV infection, 1,164 subjects positive for serum HCV antibodies and HCV RNA from three HCV hyperendemic areas (Masago, Tzukuan, and Taoyuan) and a tertiary referral center in Taiwan were studied during 1995-1997. HCV genotypes and viral loads were determined using Okamoto's method and branched DNA assay, respectively. Genotype 1b was the most prevalent in Tzukuan (61.9%), Taoyuan (76.9%), and the referral center (47.0%). By contrast, genotype 2a was the major HCV type in Masago (63.5%). Prevalence of genotype 1b positively and that of genotype 2a negatively correlated to age, regardless of study populations (P < 0.01). Based on multivariate analysis, the significant factors associated with the presence of cirrhosis, with or without hepatocellular carcinoma, in chronic hepatitis C patients were genotype 1b and age. In conclusion, these results underline that independent HCV outbreaks continue in HCV hyperendemic areas in Taiwan, concomitant with a changing relative prevalence of HCV genotypes in relation to age. Both the correlation of genotype 1b with age (cohort effect) and intrinsic properties of HCV genotypes are probably responsible for the association between genotype and the pathogenesis of HCV infection.

The most prevalent hepatitis C virus genotypes in England and Wales are 3a and 1a

Hepatitis C virus (HCV) genotypes were assigned to 567 individuals by restriction fragment length polymorphism analysis of the 5' noncoding region of the HCV genome following reverse transcription-polymerase chain reaction. The groups of individuals in this study included hemophilia patients, injecting drug users (IDUs), blood donors, antenatal patients, those attending genitourinary medicine (GUM) clinics, and patients with chronic liver disease, all from England and Wales. The majority of HCV infections were types 1a (32%), 1b (15%), or 3a (37%). The genotype distribution in individual groups was similar to the overall genotype distribution except for hemophilia patients, in whom the frequencies were 1a (39%), 1b (23%), and 3a (21%). With the exception of hemophilia patients, subpopulations in England and Wales appear to share common modes of HCV transmission. There is a need for continued surveillance to monitor the spread of possibly more virulent or drug-resistant HCV genotypes.