Effect of adding daclatasvir in sofosbuvir-based therapy in genotype 3 hepatitis C: real-world experience in Pakistan

HepFREEPak: protocol for a multi-centre, prospective observational study examining efficacy and impact of current therapies for the treatment of hepatitis C in Pakistan and reporting resistance to antiviral drugs: study protocol

BACKGROUND

Pakistan has one of the highest burdens of Hepatitis C virus (HCV) infection globally. To achieve the World Health Organization's goals for HCV elimination, there is a need for substantial scale-up in testing, treatment, and a reduction in new infections. Data on the population impact of scaling up treatment is not available in Pakistan, nor is there reliable data on the incidence of infection/reinfection. This project will fill this gap by providing important empirical data on the incidence of infection (primary and reinfection) in Pakistan. Then, by using this data in epidemic models, the study will determine whether response rates achieved with affordable therapies (sofosbuvir plus daclatasvir) will be sufficient to eliminate HCV in Pakistan.

METHODS

This prospective multi-centre cohort study will screen 25,000 individuals for HCV antibody (Ab) and RNA (if Ab-positive) at various centers in Pakistan- Karachi (Sindh) and Punjab, providing estimates of the disease prevalence. HCV positive patients will be treated with sofosbuvir and daclatasvir for 12-weeks, (extended to 24-weeks in those with cirrhosis) and the proportion responding to this first-line treatment estimated. Patients who test HCV Ab negative will be recalled 12 months later to test for new HCV infections, providing estimates of the incidence rate. Patients diagnosed with HCV (~ 4,000) will be treated and tested for Sustained Virological Response (SVR). Questionnaires to assess risk factors, productivity, health care usage and quality of life will be completed at both the initial screening and at 12-month follow-up, allowing mathematical modelling and economic analysis to assess the current treatment strategies. Viral resistance will be analysed and patients who have successfully completed treatment will be retested 12 months later to estimate the rate of re-infection.

CONCLUSION

The HepFREEPak study will provide evidence on the efficacy of available and widely used treatment options in Pakistan. It will also provide data on the incidence rate of primary infections and re-infections. Data on incidence risk factors will allow us to model and incorporate heterogeneity of risk and how that affects screening and treatment strategies. These data will identify any gaps in current test-and-treat programs to achieve HCV elimination in Pakistan.

STUDY REGISTRATION

This study was registered on clinicaltrials.gov (NCT04943588) on June 29, 2021.

Daclatasvir as a hepatitis C infection treatment option: an up-to-date evaluation

INTRODUCTION

Globally, it is estimated that 290,000 patients infected with hepatitis C virus (HCV) died from hepatitis C consequences, including cirrhosis and hepatocellular carcinoma in 2019. Although daclatasvir (DCV), combined with sofosbuvir (SOF), is effective in HCV patients, the new pan-genotypic combinations are considered by many as more cost-effective and successful in eradicating HCV infection.

AREAS COVERED

This review discusses the safety, efficacy, and cost-effectiveness of DCV as an HCV treatment option based on real-world studies and pharmacoeconomic evaluations.

EXPERT OPINION

Real-life studies suggest that SOF/DCV has acceptable sustained virological response and can be used successfully to manage HCV. Nonetheless, the use of SOF/DCV is limited by the longer treatment duration in genotype (GT)-3 patients and the need for ribavirin (RBV) in treatment-experienced patients which increases the likelihood of adverse effects. DCV is likely to remain as a therapeutic option for the management of GT-1, GT-2, and GT-4 patients in resource limited settings, while GT-3 patients are more likely to benefit from RBV-free direct-acting antiviral combinations such as SOF/velpatasvir for 12 weeks or glecaprevir/pibrentasvir for 8 weeks. The introduction of generics for these new pan-genotypic drugs would likely eliminate the need for SOF/DCV in the near future.

Selection dynamics of HCV genotype 3 resistance-associated substitutions under direct-acting antiviral therapy pressure

The chronic hepatitis C (CHC) treatment is currently based on the use of direct-acting antivirals (DAAs), and patients infected with hepatitis C virus genotype 3 (GT3) have emerged as a more difficult-to-cure population. The NS5A inhibitor daclatasvir (DCV) and sofosbuvir (SOF), an NS5B viral polymerase inhibitor, are among the drugs that compose more effective and safer treatment regimens. The virus genetic variability is related to resistance-associated substitutions (RASs) that adversely impact DAAs effectiveness. The aims of this study were to analyze the association of NS5A and NS5B RASs and other clinical factors with DAAs regimens effectiveness in patients with GT3 CHC infection. This was a prospective cohort study performed in a Brazilian university hospital. Individuals older than 18 years with GT3 CHC treated with SOF + DCV ± ribavirin (RBV) or SOF + peginterferon (PEG) + RBV were included. Blood samples were collected at baseline and post-treatment. A total of 121 patients were included. Sustained virological response rates were 87.6% for the SOF + DCV ± RBV group and 80.0% for the SOF + PEG + RBV arm. Cirrhosis, prior treatment with interferon/PEG + RBV, and baseline NS5A RAS were associated with higher risk of treatment failure. The NS5A analysis suggested that A30K, Y93H, and RAS at site 62 were related to failure. Interestingly, a likely compensatory effect was shown between A30K and A62T. Emergence of Y93H was always associated with RAS at position 62. The RASs dynamics comprehension is an important tool to indicate more effective treatment for GT3 patients.

Real-World Effectiveness of Direct-Acting Antiviral Regimens against Hepatitis C Virus (HCV) Genotype 3 Infection: A Systematic Review and Meta-Analysis

Patients with hepatitis C virus (HCV) genotype 3 (GT3) infection are resistant to direct-acting antiviral (DAA) treatments. This study aimed to analyze the effectiveness of sofosbuvir (SOF)+daclatasvir (DCV) ± ribavirin (RBV); SOF+velpatasvir (VEL)±RBV; SOF+VEL+voxilaprevir (VOX); and glecaprevir (GLE)+pibrentasvir (PIB) in the treatment of HCV GT3-infected patients in real-world studies. Articles were identified by searching the PubMed, EMBASE, and Cochrane Library databases from January 1, 2016 to September 10, 2019. The meta-analysis was conducted to determine the sustained virologic response (SVR) rate, using R 3.6.2 software. Thirty-four studies, conducted on a total of 7328 patients from 22 countries, met the inclusion criteria. The pooled SVR rate after 12/24 weeks of treatment was 92.07% (95% CI: 90.39-93.61%) for the evaluated regimens. Also, the SVR rate was 91.17% (95% CI: 89.23-92.94%) in patients treated with SOF+DCV±RBV; 95.08% (95% CI: 90.88-98.13%) in patients treated with SOF+VEL±RBV; 84.97% (95% CI: 73.32-93.91%) in patients treated with SOF+VEL+VOX; and 98.54% (95% CI: 96.40-99.82%) in patients treated with GLE+PIB. The pooled SVR rate of the four regimens was 95.24% (95% CI: 93.50-96.75%) in non-cirrhotic patients and 89.39% (95% CI: 86.07-92.33%) in cirrhotic patients. The pooled SVR rate was 94.41% (95% CI: 92.02-96.42%) in treatment-naive patients and 87.98% (95% CI: 84.31-91.25%) in treatment-experienced patients. The SVR rate of GLE+PIB was higher than other regimens. SOF+VEL+VOX can be used as a treatment regimen following DAA treatment failure.

Sofosbuvir-Based Therapies Achieved Satisfactory Virological Response in Chinese Individuals with Genotypes 3 and 6 Infections: A Real-World Experience

BACKGROUND

Previous studies have shown that sofosbuvir-based regimens yield high sustained virological response rates in patients with hepatitis C virus (HCV) infection except for genotype 3b complicated with cirrhosis. This real-world study aims to explore the efficacy and safety of sofosbuvir-based regimens in Chinese patients with genotypes 3 and 6 infections, especially the impact of ribavirin coadministration on sustained virological response in cirrhotic patients with genotype 3b infection.

METHODS

This is a retrospective cohort study that included 101 patients initiated on sofosbuvir-based regimens. The main endpoint of treatment was sustained virological response at posttreatment week 12 (SVR12).

RESULTS

Overall, the SVR12 rates were 95.0% (96/101); specifically, the rates were 100% in sofosbuvir, 88.2% in sofosbuvir+ribavirin, 100% in sofosbuvir+daclatasvir, 100% in sofosbuvir+daclatasvir+ribavirin, 95.0% in sofosbuvir/velpatasvir, and 97.1% in sofosbuvir/velpatasvir+ribavirin (p=0.534). The SVR12 rates were comparable in patients infected with genotypes 3 and 6 (93.2% versus 97.6%, p=0.339). The SVR12 rate was 93.9% in cirrhotic patients (31/33). Among those infected with genotype 3, the SVR12 rate was 91.7% (22/24); the rate was 95.0% in those with ribavirin coadministration regimens, which was numerically higher than the 75.0% in those without ribavirin. However, no statistical difference was found (p=0.312). In total, five patients failed to achieve SVR12, including 3 patients with genotype 3b infection treated with ribavirin coadministration regimens (one of them was cirrhotic), 1 cirrhotic patient with genotype 3k infection, and 1 noncirrhotic patient with genotype 6a infection. No severe adverse event occurred.

CONCLUSION

Real-world data show that sofosbuvir-based regimens are highly effective and safe for patients with HCV genotypes 3 and 6 infections.

Hepatocellular carcinoma occurs frequently and early after treatment in HCV genotype 3 infected persons treated with DAA regimens

BACKGROUND

There are conflicting data regarding the risk of hepatocellular carcinoma (HCC) after direct-acting antiviral agent (DAA) treatment. Risk of HCC in HCV genotype-3 infected persons after DAA therapy is not well known.

METHODS

We prospectively studied HCV infected persons initiated on a DAA regimen between October 2014 and March 2017 at two centers in Pakistan. All persons were free of HCC at study initiation. HCC was confirmed based on characteristic CT scan findings. Patients were followed for 12 months after the completion of therapy.

RESULTS

A total of 662 persons initiated treatment. Median age (IQR) was 50 (41, 57) years and 48.8% were male. At baseline, 49.4% were cirrhotic, 91% were genotype 3 and 91.9% attained SVR. Treatment regimens used were: Sofosbuvir (SOF)/ribavirin (RBV)/pegylated interferon (PEG-IFN), 25.2%; SOF/RBV, 62.4%; SOF/RBV/daclatasavir (DCV), 10.6%; SOF/DCV, 2.0%. Incident HCC was detected in 42 patients (12.8%) in the 12-month period after treatment completion and was exclusively observed in those with cirrhosis. In multivariable Cox regression analysis, SVR was associated with a reduction in HCC risk (HR, 95% CI: 0.35, 0.14,0.85). In Kaplan-Meier plots by treatment regimen, those treated with SOF/RBV, SOF/RBV/DCV, or SOF/DCV regimens had a shorter HCC-free survival compared with those treated with a SOF/RBV/PEG-IFN regimen.

CONCLUSION

In a predominantly genotype 3 cohort, incident HCC occurred frequently and early after treatment completion, and exclusively in those with pre-treatment cirrhosis. SVR reduced the risk of HCC. Treating HCV infected persons before development of cirrhosis may reduce risk of HCC.