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

Is there still hope for the prophylactic hepatitis C vaccine? A review of different approaches

Despite remarkable progress in the treatment of hepatitis C virus (HCV) infection, it remains a significant global health burden, necessitating the development of an effective prophylactic vaccine. This review paper presents the current landscape of HCV vaccine candidates and approaches, including more traditional, based on inactivated virus, and more modern, such as subunit protein, vectored, based on nucleic acids (DNA and mRNA) and virus-like particles. The concept of the HCV vaccine is first put in the context of viral genetic diversity and adaptive responses to HCV infection, an understanding of which is crucial in guiding the development of an effective vaccine against such a complex virus. Because ethical dimensions are also significant in vaccine research, development, and potential deployment, we also address them in this paper. The road to a safe and effective vaccine to prevent HCV infection remains bumpy due to the genetic variation of HCV and its ability to evade immune responses. The progress in cell-culture systems allowed for the production of an inactivated HCV vaccine candidate, which can induce cross-neutralizing antibodies in vitro, but whether this could prevent infection in humans is unknown. Subunit protein vaccine candidates that entered clinical trials elicited HCV-specific humoral and cellular responses, though it remains to be shown whether they translate into effective prevention of HCV infection or progression of infection to a chronic state. Such responses were also induced by a clinically tested vector-based vaccine candidate, which decreased the viral HCV load but did not prevent chronic HCV infection. These disappointments were not readily predicted from preclinical animal studies. The vaccine platforms employing virus-like particles, DNA, and mRNA provide opportunities for the HCV vaccine, but their potential in this context has yet to be shown. Ensuring the designed vaccine is based on conserved epitope(s) and elicits broadly neutralizing immune responses is also essential. Given failures in developing a prophylactic HCV vaccine, it is crucial to continue supporting national strategies, including funding for screening and treatment programs. However, these actions are likely insufficient to permanently control the HCV burden, encouraging further mobilization of significant resources for HCV vaccine research as a missing element in the elimination of viral hepatitis as a global public health.

Personalized care approaches to hepatitis C therapy: recent advances and future directions

INTRODUCTION

The introduction of direct-acting antivirals (DAAs) has significantly transformed the therapeutic landscape for chronic C hepatitis virus (HCV) infection. However, there is still room for further improvement in optimizing therapy efficacy and minimizing adverse effects.

AREAS COVERED

This review is devoted to the rationale for adopting a personalized approach to HCV therapy. Specifically, we explore the role of host-related factors, such as sex or the presence of comorbidities. We thoroughly examine the implications of commonly encountered comorbidities, including HIV infection, chronic renal disease, liver cirrhosis, and other chronic viral hepatitis infections. Additionally, we discuss the prevalent drug-to-drug interactions between DAAs and other medications, while providing guidance on their management. Finally, we investigate viral-related issues that can influence treatment outcomes, such as viral genotype, quasi-species, and the presence of resistance-associated mutations.

EXPERT OPINION

Despite pivotal trials demonstrating efficacy rates exceeding 90% for currently available DAA regimens, there are still opportunities to optimize therapy outcomes and tailor treatment to each patient. This can be achieved through a meticulous evaluation of the patient's specific clinical conditions and comorbidities, a vigilant approach to manage potential drug interactions, and diligent patient follow-up.

Incidence of hepatocellular carcinoma and mortality in chronic viral hepatitis in an Asian population with and without HIV infection

BACKGROUND

It is uncertain whether people with HIV infection have a higher incidence of hepatocellular carcinoma (HCC) than the general population.

AIMS

To compare the incidence of HCC between people infected with HBV and/or HCV with and without HIV METHODS: We performed a retrospective population-based cohort study, involving people with HBV and/or HCV infection from 2001 to 2018. The primary endpoint was incidence of HCC; secondary endpoint was all-cause mortality. We performed Cox proportional hazard regression models to estimate the hazard ratios (HR) of HIV for the primary and secondary endpoints.

RESULTS

We identified 1374 people infected with HIV and 39,908 people without HIV with HBV and/or HCV infection. Among those with HIV, 654 (47.6%) had HBV, 649 (47.2%) HCV and 71 (5.2%) HBV-HCV-co-infection; they were younger, and had a higher prevalence of HCV and a lower prevalence of cirrhosis. The incidence rate estimates of HCC were, respectively, 1.5 (95% CI: 0.8-2.5) and 7.6 (95% CI 7.3-8.0) per 1000 person-years for those with and without HIV infection. Using multivariate Cox proportional hazard regression models, among people with HBV, HIV was associated with lower risk of HCC (adjusted HR: 0.376, 95% CI: 0.201-0.704, p = 0.01) and death (adjusted HR: 0.692, 95% CI: 0.552-0.867, p = 0.007). Risks of HCC were similar for HCV and HBV-HCV co-infection for people with and without HIV.

CONCLUSIONS

Among individuals with HBV infection, the Incidence of HCC was lower in those with HIV. For HCV infection, incidence of HCC was similar between those with and without HIV.

Evolution of estimated glomerular filtration rate in HIV/HCV-coinfected patients who received direct-acting antivirals: A multicenter retrospective study

BACKGROUND

The short-term impact of sofosbuvir (SOF)-based direct-acting antivirals (DAAs) combined with antiretroviral therapy (ART) on renal function in patients with HIV/HCV-coinfection remains controversial.

METHODS

This multicenter, retrospective study aimed to sequentially record the estimated glomerular filtration rate (eGFR) at baseline, end of therapy (EOT), 12 weeks off-treatment (SVR12), and at time points after SVR12 (post-SVR12) and to identify the factors associated with an eGFR decline to <60 ml/min/1.73 m2 in HIV/HCV-coinfected patients receiving DAAs. The evolution of mean eGFRs between different ART and DAAs combinations among patients of different HIV transmission routes were compared using a generalized linear mixed effects model. The periods between baseline and EOT, between EOT and post-SVR12, and between baseline and post-SVR12 were defined as the on-treatment, post-treatment, and all-course periods, respectively. Acute kidney disease (AKD) was defined as a decline of eGFR to <60 ml/min/1.73 m2.

RESULT

A total of 445 patients with baseline eGFRs >60 ml/min/1.73 m2 were included. We found that eGFRs declined during the on-treatment period in the tenofovir-containing ART and SOF-based DAA groups. There were no differences in the slope coefficient during the on-treatment and post-treatment periods among all risk groups except for people who inject drug. Increasing age and plasma HIV RNA >20 copies/ml before DAA treatment were factors independently associated with AKD during the on-treatment period while increasing age was independently associated with AKD during the all-course period.

CONCLUSION

Only increasing age was an independent factor associated with AKD among HIV/HCV-coinfected patients during and after DAA treatments.

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.

Performance of Hepatitis C Virus (HCV) Core Antigen Assay in the Diagnosis of Recently Acquired HCV Infection among High-Risk Populations

How the hepatitis C virus (HCV) core antigen (HCVcAg) assay performs in detecting recently acquired HCV infection among people living with HIV (PLWH) and HIV-negative men who have sex with men (MSM) is rarely assessed in the Asia-Pacific region. High-risk participants, including PLWH with sexually transmitted infections (STIs), HCV clearance by antivirals or spontaneously, or elevated aminotransferases, HIV-negative MSM with STIs or on HIV preexposure prophylaxis, and low-risk PLWH were enrolled. Blood samples were subjected to 3-stage pooled-plasma HCV RNA testing every 3 to 6 months until detection of HCV viremia or completion of the 1-year follow-up. The samples at enrollment and all of the archived samples preceding the detection of HCV RNA during follow-up were tested for HCVcAg. During June 2019 and February 2021, 1,639 blood samples from 744 high-risk and 727 low-risk PLWH and 86 HIV-negative participants were tested for both HCV RNA and HCVcAg. Of 62 samples positive for HCV RNA, 54 (87.1%) were positive for HCVcAg. Of 1,577 samples negative for HCV RNA, 1,568 (99.4%) were negative for HCVcAg. The mean HCV RNA load of the 8 individual samples positive for HCV RNA but negative for HCVcAg was 3.2 (range, 2.5 to 3.9) log10 IU/mL, and that of the remaining 54 samples with concordant results was 6.2 (range, 1.3 to 8.5) log10 IU/mL. The positive predictive value (PPV) and negative predictive value (NPV) of HCVcAg were 85.7% and 99.5%, respectively. In at-risk populations, HCVcAg has a high specificity and NPV but lower sensitivity and PPV, particularly in individuals with low HCV RNA loads. IMPORTANCE The HCV core antigen assay has a high specificity of 99.4% and negative predictive value of 99.5% but a lower sensitivity of 87.1% and positive predictive value of 85.7% in the diagnosis of recently acquired HCV infection in high-risk populations. Our findings are informative for many countries confronted with limited resources to timely identify acute HCV infections and provide effective direct-acting antivirals to halt onward transmission.