Era Of Direct-acting Antiviral Agents Research Articles

Geno2pheno[HCV] - A Web-based Interpretation System to Support Hepatitis C Treatment Decisions in the Era of Direct-Acting Antiviral Agents.

The face of hepatitis C virus (HCV) therapy is changing dramatically. Direct-acting antiviral agents (DAAs) specifically targeting HCV proteins have been developed and entered clinical practice in 2011. However, despite high sustained viral response (SVR) rates of more than 90%, a fraction of patients do not eliminate the virus and in these cases treatment failure has been associated with the selection of drug resistance mutations (RAMs). RAMs may be prevalent prior to the start of treatment, or can be selected under therapy, and furthermore they can persist after cessation of treatment. Additionally, certain DAAs have been approved only for distinct HCV genotypes and may even have subtype specificity. Thus, sequence analysis before start of therapy is instrumental for managing DAA-based treatment strategies. We have created the interpretation system geno2pheno[HCV] (g2p[HCV]) to analyse HCV sequence data with respect to viral subtype and to predict drug resistance. Extensive reviewing and weighting of literature related to HCV drug resistance was performed to create a comprehensive list of drug resistance rules for inhibitors of the HCV protease in non-structural protein 3 (NS3-protease: Boceprevir, Paritaprevir, Simeprevir, Asunaprevir, Grazoprevir and Telaprevir), the NS5A replicase factor (Daclatasvir, Ledipasvir, Elbasvir and Ombitasvir), and the NS5B RNA-dependent RNA polymerase (Dasabuvir and Sofosbuvir). Upon submission of up to eight sequences, g2p[HCV] aligns the input sequences, identifies the genomic region(s), predicts the HCV geno- and subtypes, and generates for each DAA a drug resistance prediction report. g2p[HCV] offers easy-to-use and fast subtype and resistance analysis of HCV sequences, is continuously updated and freely accessible under http://hcv.geno2pheno.org/index.php. The system was partially validated with respect to the NS3-protease inhibitors Boceprevir, Telaprevir and Simeprevir by using data generated with recombinant, phenotypic cell culture assays obtained from patients’ virus variants.

Statin (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor)-based therapy for hepatitis C virus (HCV) infection-related diseases in the era of direct-acting antiviral agents

Recent improvements have been made in the treatment of hepatitis C virus (HCV) infection with the introduction of direct-acting antiviral agents (DAAs). However, despite successful viral clearance, many patients continue to have HCV-related disease progression. Therefore, new treatments must be developed to achieve viral clearance and prevent the risk of HCV-related diseases. In particular, the use of pitavastatin together with DAAs may improve the antiviral efficacy as well as decrease the progression of liver fibrosis and the incidence of HCV-related hepatocellular carcinoma. To investigate the management methods for HCV-related diseases using pitavastatin and DAAs, clinical trials should be undertaken. However, concerns have been raised about potential drug interactions between statins and DAAs. Therefore, pre-clinical trials using a replicon system, human hepatocyte-like cells, human neurons and human cardiomyocytes from human-induced pluripotent stem cells should be conducted. Based on these pre-clinical trials, an optimal direct-acting antiviral agent could be selected for combination with pitavastatin and DAAs. Following the pre-clinical trial, the combination of pitavastatin and the optimal direct-acting antiviral agent should be compared to other combinations of DAAs ( e.g., sofosbuvir and velpatasvir) according to the antiviral effect on HCV infection, HCV-related diseases and cost-effectiveness.

Race and Gender Differences in the Use of Direct Acting Antiviral Agents for Hepatitis C Virus.

Direct acting antiviral agents (DAA) are highly effective yet expensive. Disparities by race and/or gender often exist in the use of costly medical advances as they become available. We examined a cohort of hepatitis C virus (HCV) patients who received care at the Veterans Administration facilities nationwide. We evaluated the effect of race and gender on DAA receipt after adjusting for socioeconomic status, liver disease severity, comorbidity, and propensity for healthcare use. To determine if disparities had changed over time, we conducted a similar analysis of HCV patients who were seen in the previous standard of care treatment era. Of the 145 596 patients seen in the current DAA era, 17 791 (10.2%) received treatment during the first 16 months of DAA approval. Black patients had 21% lower odds of receiving DAA than whites (odds ratio [OR] = 0.79; 95% confidence interval [CI], .75, .84). Overall, women were as likely to receive treatment as men (OR = 0.99; 95% CI, .90-1.09). However, the odds of receiving DAAs were 29% lower for younger women compared with younger men (OR = 0.71, 95% CI, .54-.93). Similar to the DAA cohort, black patients had significantly lower odds of receiving treatment than whites (OR = 0.74, 95% CI, .69-.79) in the previous treatment era. The racial difference between the 2 eras did not reach statistical significance. There were unexplained differences among HCV population subgroups in the receipt of new DAA treatment. Targeted interventions are needed for black patients and younger women.

Type 2 Diabetes in Non-Alcoholic Fatty Liver Disease and Hepatitis C Virus Infection--Liver: The "Musketeer" in the Spotlight.

The pathogenesis of type 2 diabetes (T2D) involves chronic hyperinsulinemia due to systemic and hepatic insulin resistance (IR), which if uncorrected, will lead to progressive pancreatic beta cell failure in predisposed individuals. Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of fatty (simple steatosis and steatohepatitis) and non-fatty liver changes (NASH-cirrhosis with or without hepatocellular carcinoma (HCC)) that are commonly observed among individuals with multiple metabolic derangements, notably including visceral obesity, IR and T2D. Hepatitis C virus (HCV) infection is also often associated with both hepatic steatosis and features of a specific HCV-associated dysmetabolic syndrome. In recent years, the key role of the steatotic liver in the development of IR and T2D has been increasingly recognized. Thus, in this comprehensive review we summarize the rapidly expanding body of evidence that links T2D with NAFLD and HCV infection. For each of these two liver diseases with systemic manifestations, we discuss the epidemiological burden, the pathophysiologic mechanisms and the clinical implications. To date, substantial evidence suggests that NAFLD and HCV play a key role in T2D development and that the interaction of T2D with liver disease may result in a “vicious circle”, eventually leading to an increased risk of all-cause mortality and liver-related and cardiovascular complications. Preliminary evidence also suggests that improvement of NAFLD is associated with a decreased incidence of T2D. Similarly, the prevention of T2D following HCV eradication in the era of direct-acting antiviral agents is a biologically plausible result. However, additional studies are required for further clarification of mechanisms involved.

Statin (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor)-based therapy for hepatitis C virus (HCV) infection-related diseases in the era of direct-acting antiviral agents.

Recent improvements have been made in the treatment of hepatitis C virus (HCV) infection with the introduction of direct-acting antiviral agents (DAAs). However, despite successful viral clearance, many patients continue to have HCV-related disease progression. Therefore, new treatments must be developed to achieve viral clearance and prevent the risk of HCV-relateddiseases. In particular, the use of pitavastatin together with DAAs may improve the antiviral efficacy as well as decrease the progression of liver fibrosis and the incidence of HCV-related hepatocellular carcinoma. To investigate the management methods for HCV-related diseases using pitavastatin and DAAs, clinical trials should be undertaken. However, concerns have been raised about potential drug interactions between statins and DAAs. Therefore, pre-clinical trials using a replicon system and human hepatocyte-like cells from human-induced pluripotent stem cells should be conducted. Based on these pre-clinical trials, an optimal direct-acting antiviral agent could be selected for combination with pitavastatin and DAAs. Following the pre-clinical trial, the combination of pitavastatin and the optimal direct-acting antiviral agent should be compared to other combinations of DAAs ( e.g., sofosbuvir and velpatasvir) according to the antiviral effect on HCV infection, HCV-related diseases and cost-effectiveness.

Ribavirin: Past, present and future.

Before the advent of direct acting antiviral agents (DAAs) ribavirin, associated to pegylated-interferon played a crucial role in the treatment of chronic hepatitis C, preventing relapses and breakthroughs. In the present era of new potent DAAs, a place is still devoted to the drug. Ribavirin associated with sofosbuvir alone is efficient in the treatment of most cases of G2 infected patients. All options currently available for the last difficult-to-treat cirrhotic G3 patients contain ribavirin. Reducing treatment duration to 12 wk in G1 or G4 cirrhotic compensated patients is feasible thanks to ribavirin. Retreating patients with acquired anti NS5A resistance-associated variants using ribavirin-based strategies could be useful. The addition of ribavirin with DAAs combinations however, leads to more frequent but mild adverse events especially in cirrhotic patients. Preliminary data with interferon-free second generation DAAs combinations without ribavirin suggest that future of the drug is jeopardized even in difficult-to-treat patients: The optimization of ribavirin dosage according to an early monitoring of blood levels has been suggested to be relevant in double therapy with peginterferon or sofosbuvir but not with very potent combinations of more than two DAAs.

Hepatitis C Virus Infection in Patients Undergoing Hematopoietic Cell Transplantation in the Era of Direct-Acting Antiviral Agents

There is paucity of literature regarding hepatitis C virus (HCV) infection in hematopoietic cell transplant (HCT) recipients. In the study described herein we evaluated several aspects of HCV infection in HCT recipients, including the impact of this infection on cancer status, liver-related outcomes, mortality, and the role of antiviral treatment (AVT), including direct-acting antivirals (DAAs). The medical records of HCV-infected allogeneic and autologous HCT recipients, seen at The University of Texas MD Anderson Cancer Center from August 2009 to November 2015, were reviewed. Patients seen from August 1, 2009 to October 30, 2012 were reviewed retrospectively, whereas those seen from November 1, 2012 to November 30, 2015 were analyzed prospectively in an observational study. Of 434 HCV-infected cancer patients evaluated, 64 underwent 69 HCTs. Most (78%) underwent autologous transplantation. Thirteen percent of patients became HCV-seronegative post-HCT. Compared with patients who did not receive AVT, treated patients had fewer relapses of HCV-associated non-Hodgkin lymphomas (20% versus 86%; P = .015), higher 5-year survival rates (75% versus 39%; P = .02), and a trend toward lower rate of progression to cirrhosis (5% versus 21%; P = .06). AVT discontinuation rate post-HCT was 71% in those receiving IFN-containing regimens and 0% in those receiving DAAs (P < .01). AVT was effective in 12 of 37 patients (32%) and 11 of 13 patients (85%) receiving IFN-based and DAA regimens, respectively (P = .003). HCV is an important cause of morbidity and mortality in this population. HCV seropositivity can be lost post-HCT, posing a diagnostic challenge. Treatment of HCV infection in HCT recipients improves both oncologic and hepatic outcomes. These patients can be successfully treated with DAAs.

Liver transplantation for hepatitis C virus in the era of direct-acting antiviral agents.

Liver transplantation is widely used to treat HIV patients with an end-stage liver disease, mainly decompensated cirrhosis and hepatocellular carcinoma. The results are good especially in non-hepatitis C virus (HCV)-coinfected patients. In HIV-HCV-coinfected patients, 5-year post-liver transplantation survival is around 50-55%, negatively impacted by HCV recurrence. The results of PEG-IFN/RBV are poor in terms of efficacy and safety. In patients with genotype 1 infection, triple therapy (boceprevir or telaprevir) has increased sustained virological response (SVR) rate, but drug-drug interactions (DDIs) with immunosuppressive agents and high rates of adverse events lead to forsake these combinations. Herein, we provide new data and practical management regarding HIV-HCV liver transplantation patients using new direct-acting antiviral agents (DAA). The second-generation DAA have good safety profile. In patients who are candidates for liver transplantation or are already recipients, the optimal therapeutic option is to combine the new DAA. Efficacy results have dramatically improved with greater than 90% of SVR rate in many studies enrolling HCV-monoinfected liver transplant recipients. Some concerns persist in terms of DDI. Even sparse, data regarding efficacy and safety of these regimens in HCV-HIV-coinfected liver transplantation will radically change the prognosis of this peculiar population.

Predominance of hepatitis C virus Q80K among NS3 baseline-resistance-associated amino acid variants in direct-antiviral-agent-naïve patients with chronic hepatitis: single-centre experience.

In the era of direct-acting antiviral agents (DAAs), hepatitis C virus (HCV) genotyping tests at baseline are controversial. The HCV NS3-Q80K polymorphism is associated with resistance to the recently approved NS3 inhibitor simeprevir (SMV) when combined with PEG-interferon and ribavirin (PEG-IFN/RBV) and alternative therapy should be considered for patients with baseline Q80K. The aim of this study was to provide an estimate of Q80K prevalence at baseline in a study group of 205 DAA-naïve patients (21% of them with HIV coinfection) using NS3 full-population direct sequencing to detect resistance-associated amino acid variants (RAVs). NS3 RAVs were identified in 56 patients (27.3%). Q80K was the most frequently reported one (41%), in both HIV/HCV-coinfected and HCV-monoinfected patients, but it was only detectable in cases of HCV-subtype 1a infection. Therefore, in clinical practice, an NS3-Q80K genotyping test prior to simeprevir plus PEG-IFN/RBV treatment is highly recommended.

Hepatitis C virus infection in patients undergoing hematopoietic cell transplantation in the era of direct-acting antiviral agents.

7090 Background: There is paucity of literature regarding hepatitis C virus (HCV) infection in hematopoietic cell transplant (HCT) recipients. In the study described herein, we aimed to evaluate se...

Spontaneous and post-treatment HCV clearance: relationships with health-related quality of life in HIV infection (ANRS-VESPA2 study)

Background: Post-treatment clearance of HCV is associated with improved health-related quality of life (HRQL) in HIV–HCV co-infection. However, the potential differences in HRQL between post-treatment and spontaneous clearers remain poorly documented. Methods: Linear regression models were used to assess the relationships between HCV status and HRQL (PROQOL-HIV scale) in 411 co-infected adults followed-up in French hospitals in 2011 (ANRS-VESPA2 survey). Results: After adjustment for socio-economic and clinical factors, patients previously exposed to HCV treatment showed better physical HRQL and better experience of HIV treatment than treatment-naive HCV-chronic patients. Post-treatment clearers showed better mental HRQL. Spontaneous clearers showed better experience of HIV treatment. Conclusion: Spontaneous and post-treatment HCV clearance may influence different dimensions of HRQL of HIV–HCV co-infected patients. Further studies in real-life settings are needed to document patient-reported outcomes in the era of direct-acting antiviral agents for HCV treatment.

Hepatitis C virus reinfection after liver transplant: New chances and new challenges in the era of direct-acting antiviral agents.

The first interferon-free regimens have been approved for the treatment of patients with chronic hepatitis C virus (HCV). In the liver transplant (LT) setting, these regimens are expected to have an important effect, because graft loss due to HCV recurrence is a serious problem after LT. The response to the hitherto conventional treatment with pegylated interferon and ribavirin is poor. The significantly better response rates achieved with boceprevir-based and telaprevir-based triple therapy have led to better graft and patient survival rates, but severe drug interactions with immunosuppressants limit the feasibility of this therapy for LT patients. With the approval of sofosbuvir in January 2014, of simeprevir in May 2014, and of daclatasvir in August 2014, three antiviral agents are now available and promise to be applicable without relevant adverse effects or negative interactions with immunosuppressants. Thus, 2014 marks the beginning of a new era of treatment options for HCV recurrence after LT. Although safety and efficacy studies of several interferon-free regimens for patients with HCV recurrence after LT have achieved good preliminary results, reports of clinical experiences with LT patients are scarce. The lack of randomized studies, the small number of enrolled and carefully selected patients, and the heterogeneity of these studies make the results questionable. Real-life experiences are eagerly awaited so that clinicians can estimate the usefulness and the pitfalls of these new regimens. Additionally, the high costs of these agents may limit their accessibility for many patients. The aim of this review is to summarize the current experience with and the expectations of the new direct-acting antiviral agents for LT patients.

Post-transplant course of hepatitis C after living donor liver transplantation in association with polymorphisms near IFNL3.

Donor genotype for polymorphisms near IFNL3 influences hepatitis C virus (HCV) therapy responsiveness. This relationship has not been studied in a sample of HCV-infected living donor liver transplantation (LDLT) recipients in the United States (US). We investigated the association of donor and recipient genotypes near the IFNL3 gene at a large US liver transplant center. Recipient homozygosity for rs12979860 C was associated with increased sustained virologic response (SVR) in antiviral treatment-experienced patients pretransplant (P = 0.055). Consistently, donor homozygosity for rs12979860 C was also associated with increased SVR in patients who received post-transplant antiviral therapy (P = 0.048). Transplantation of an rs12979860 CC graft confers a favorable post-transplant antiviral response among HCV-positive recipients in an LDLT setting. Recipients with the favorable rs12979860 genotype receiving antiviral therapy before transplant are also more likely to achieve SVR. The effect of genotype status in the era of direct-acting antiviral agents will require future study.

Interferon‐α/β for treatment of chronic hepatitis C infection in the era of direct‐acting antiviral agents

Type I interferons (IFN-α/β), with or without ribavirin, have been the only agents that can eradicate the hepatitis C virus (HCV). An IFN-free regimen combining oral direct-acting antiviral agents (DAA) will be approved soon for genotype 1 patients. Here, we discuss the role of IFN-α/β in the forthcoming "era of DAA" with consideration of limitations and concerns about IFN-free therapies. First, the therapeutic efficacy of first-generation DAA varies among the different subtypes. While the rate of sustained virological response (SVR) is 60-90% among patients with genotype 1b, the rate often falls short of 50% in patients with genotype 1a. IFN and ribavirin can still be indicated for patients with genotype 1a as a platform for combination with DAA. Second, there is concern about the emergence of drug-resistance resulting from inappropriate use of DAA. The clinical significance of pre-existing resistant variants has not been elucidated. Drug resistance may affect the efficacy of next-generation treatments. An IFN and ribavirin backbone in combination with DAA is an effective measure to prevent the emergence of drug resistance and/or to suppress pre-existing resistant viruses. Third, it remains unknown whether the incidence of hepatocellular carcinoma (HCC) will be reduced in patients who achieve SVR with IFN-free regimens. In contrast, there are many reports in Japan demonstrating the preventive effects of IFN on the development of HCC. When patients do not achieve SVR with first-generation DAA, low-dose IFN maintenance therapy is a treatment option until the next-generation therapy with pan-genotypic potency and high genetic barrier become available.

IFNL4 ss469415590 Variant Is Associated with Treatment Response in Japanese HCV Genotype 1 Infected Individuals Treated with IFN-Including Regimens.

Aim. Eradication of hepatitis C virus (HCV) is still challenging even if interferon- (IFN-) free regimens with direct-acting antiviral agents (DAAs) for HCV-infected individuals are available in clinical practice. IFNL4 is a newly described protein, associated with human antiviral defenses. We investigated whether IFNL4 ss469415590 variant has an effect on the prediction of treatment response in HCV-infected patients treated with IFN-including regimens. Patients and Methods. In all, 185 patients infected with HCV genotype 1 treated with peg-IFN plus ribavirin, with or without telaprevir, were genotyped for IFNL4 ss469415590. We retrospectively investigated whether the role of IFNL4 ss469415590 variant and other factors could predict sustained virological response (SVR) in Japanese patients infected with HCV genotype 1. Results. There were 65.7%, 31.5%, and 2.8% patients in the IFNL4 ss469415590 TT/TT, TT/-G, and -G/-G groups, respectively. SVR rates were 82.1% or 49.3% in patients treated with peg-IFN plus ribavirin with or without telaprevir, respectively. IFNL4 ss469415590 variant and HCV viral loads or IFNL4 ss469415590 variant and early virological response were better predictors of SVR in patients treated with peg-IFN plus ribavirin with or without telaprevir, respectively. Conclusion. In the era of DAAs, measurement of IFNL4 ss469415590 variant could help the prediction of SVR in Japanese HCV genotype 1 infected individuals treated with IFN-including regimens.

Complexities of HCV management in the new era of direct-acting antiviral agents

The availability of the direct-acting antiviral agents (DAAs) boceprevir and telaprevir provides improved treatment outcomes for many patients infected with hepatitis C virus (HCV) genotype 1. However, HCV infection must first be identified before a decision on treatment can be made and currently many patients remain unaware that they have the virus. Given the lack of prompt diagnosis, disease severity should be determined as a baseline reference for treatment, and novel non-invasive techniques for evaluating fibrosis are now available. For patients receiving a DAA regimen, response-guided therapy based on the detection, absence or level of HCV RNA at specified time points is required to achieve an optimal treatment outcome. Knowledge of the test used to measure HCV RNA and its analytical sensitivity, as well as how to interpret the results correctly, are therefore required to administer therapy appropriately. Furthermore, effective treatment management includes appropriate handling of side effects. This increased complexity associated with DAA regimens has resulted in confusion over many aspects of care, including treatment monitoring, viral load result interpretation and the optimal duration of therapy. These issues are discussed here in addition to the benefits of referring patients infected with HCV to a specialist centre.

Antiviral activity of the interferon α family: biological and pharmacological aspects of the treatment of chronic hepatitis C

Introduction: Type I interferons (IFNs) comprise a group of at least 13 structurally related subtypes of IFN-α with similar, but not identical, biological activities. Each subtype displays a unique activity profile; only IFN-α2a and IFN-α2b subtypes together with natural IFN-α preparations are currently used in the clinical practice, so that the remaining IFN-α subtypes are a still unexploited reservoir of opportunity also in the new era of direct-acting antiviral agents for the treatment of hepatitis C virus (HCV).Areas covered: This paper reviews recent progress in the study of the biology of IFN family, the antiviral action mechanism and the strategies employed by HCV to evade IFN action. Currently available IFN preparations for the treatment of chronic hepatitis C infection are described and what is currently known on the pharmacokinetics, pharmacodynamics and immunogenicity of IFN-α preparations used in clinical practice are summarized.Expert opinion: The characterization of multifunctional nature of IFN system together with recent advances in the identification of HCV IFN evasion strategies and the variety of host factors influencing IFN treatment response should be considered to improve HCV and other infectious diseases treatment in the future.

Will IL28B polymorphism remain relevant in the era of direct-acting antiviral agents for hepatitis C virus?

Will IL28B polymorphism remain relevant in the era of direct-acting antiviral agents for hepatitis C virus?

Mathematical modelling of HCV infection: what can it teach us in the era of direct-acting antiviral agents?

HCV infection is a major cause of chronic liver disease and affects nearly 170 million people worldwide. Whereas the previous standard of care with pegylated interferon and ribavirin had a modest effectiveness, the recent approval of two highly potent protease inhibitors and the ongoing development of dozens of direct-acting antiviral agents (DAAs) constitute a major milestone for HCV therapy. Mathematical modelling of viral kinetics under treatment has played an instrumental role in improving our understanding of virus pathogenesis and in guiding drug development. Here, we review the current state of HCV kinetic modelling, and challenges to the standard biphasic viral decline model that arise when fitting viral kinetic models to data obtained with DAAs.

Understanding hepatitis C viral dynamics with direct-acting antiviral agents due to the interplay between intracellular replication and cellular infection dynamics

The current paradigm for modeling viral kinetics and resistance evolution after treatment initiation considers only the level of circulating virus and cellular infection (CI model), while the intra-cellular level is disregarded. This model was successfully used to explain HIV dynamics and Hepatitis C virus (HCV) dynamics during interferon-based therapy. However, in the new era of direct-acting antiviral agents (DAAs) against HCV, viral kinetics is characterized by a more rapid decline of the wild-type virus as well as an early emergence of resistant strains that jeopardize the treatment outcome. Although the CI model can be extended to describe these new kinetic patterns, this approach has qualitative and quantitative limitations. Instead, we suggest that a more appropriate approach would consider viral dynamics at the cell infection level, as done currently, as well as at the intracellular level. Indeed, whereas in HIV integrated DNA serves as a static replication unit and mutations occur only once per infected cell, HCV replication is deeply affected by DAAs and furthermore processes of resistance evolution can occur at the intra-cellular level with a faster time-scale. We propose a comprehensive model of HCV dynamics that considers both extracellular and intracellular levels of infection (ICCI model). Intracellular viral genomic units are used to form replication units, which in turn synthesize genomic units that are packaged and secreted as virions infecting more target cells. Resistance evolution is modeled intra-cellularly, by different genomic- and replication-unit strains with particular relative-fitness and drug sensitivity properties, allowing for a rapid resistance takeover. Using the ICCI model, we show that the rapid decline of wild-type virus results from the ability of DAAs to destabilize the intracellular replication. On the other hand, this ability also favors the rapid emergence, intracellularly, of resistant virus. By considering the interaction between intracellular and extracellular infection we show that resistant virus, able to maintain a high level of intracellular replication, may nevertheless be unable to maintain rapid enough de novo infection rate at the extracellular level. Hence this model predicts that in HCV, and contrary to our experience with HIV, the emergence of productively resistant virus may not systematically prevent from a viral decline in the long-term. Thus, the ICCI model can explain the transient viral rebounds observed with DAA treatment as well as the viral resistance found in most patients with viral relapse at the end of DAA combination therapy.