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.     

Hepatitis C treatment from “response‐guided” to “resource‐guided” therapy in the transition era from interferon‐containing to interferon‐free regimens

Peginterferon/ribavirin has been the standard‐of‐care for chronic hepatitis C virus (HCV) infections: 48 weeks for genotype 1 or 4 (HCV‐1/4) and 24 weeks for HCV‐2/3. Response‐guided therapy recommended shorter 24‐ and 16‐week regimens for HCV‐1 with lower baseline viral loads (< 400 000–800 000 IU/mL) and rapid virological response (RVR, undetectable HCV RNA at week 4) and HCV‐2/3 with RVR, respectively; and extending to 72 and 48 weeks for HCV‐1 slower responders and HCV‐2 non‐RVR patients, respectively, to improve the efficacy. The progress of directly acting antivirals (DAA), moving from interferon‐containing regimens in 2011 to interferon‐free regimens in 2013, has greatly improved the treatment success. Interferon‐containing regimens include boceprevir or telaprevir or simeprevir or daclatasvir plus peginterferon/ribavirin, 24–48 weeks, for HCV‐1 or 4. However, adding these DAA has no benefit for HCV‐1 with lower baseline viral loads/RVR. Instead, 12‐week sofosbuvir plus peginterferon/ribavirin attained sustained virological response rates of > 90% for HCV‐1/3–6. Interferon‐free regimens include two main categories: NS5B nucleotide inhibitor (sofosbuvir)‐based regimens and NS3/4A inhibitor/NS5A inhibitor‐based regimens (daclatasvir/asunaprevir, paritaprevir/r/ombitasvir/dasabuvir and grazoprevir/elbasvir). About 8–24 weeks interferon‐free regimens could achieve sustained virological response rates of 82–99% for corresponding HCV genotypes. Although the newly DAA interferon‐free regimens have high efficacy and safety, the huge budget impact increases the treatment barriers. The current recommendation should, therefore, base on the availability, indication, and cost‐effectiveness in the transition era of DAA. Based on the concept of “resource‐guided therapy,” peginterferon/ribavirin might be applied for easy‐to‐treat interferon‐eligible patients in resource‐constrained areas. Prioritizing patients for interferon‐free regimens according to “time‐degenerative factors” (age and fibrosis) is justified before the regimens becoming available and affordable.     

Interferon‐free,direct‐acting antiviral therapy for chronic hepatitis C

The treatment environment for chronic hepatitis C has undergone a revolution, particularly in genotype 1. Gone are interferon‐based therapy and its associated tolerability challenges, inadequate response rates and numerous baseline factors that affect response to therapy. New and emerging treatment regimens employ all‐oral combinations of direct‐acting antiviral agents, and results of clinical trials suggest that these regimens routinely achieve cure rates >90%, even in patients who failed prior interferon‐based triple therapy. In 2015, three all‐oral FDA‐approved regiments will be available for genotype 1 (sofosbuvir /ledipasvir, sofosbuvir/simeprevir, and paritaprevir/r/ombitasvir/dasabuvir). Furthermore, new treatment combinations appear to be more tolerable and require shorter duration of therapy. We provide an overview of the classes of direct‐acting antiviral agents (DAAs), the clinical factors affecting their integration into combination therapies and recent findings from trials of such combination therapies in patients with genotype 1 HCV infection.     

Comparing the risk of hepatitis B virus reactivation between direct‐acting antiviral therapies and interferon‐based therapies for hepatitis C

Hepatitis B virus (HBV) reactivation has been reported during antihepatitis C treatment in patients with hepatitis C virus (HCV) and HBV co‐infection. We aimed to evaluate the frequency and risk factors of HBV reactivation during anti‐HCV therapy and compared those between interferon (IFN)‐free direct‐acting antiviral (DAA) therapies and IFN‐based therapies. Three hundred and twenty‐two patients with HCV infection receiving anti‐HCV therapy were retrospectively screened. The baseline HBV infection statuses of all eligible patients and the HBV‐DNA level of all patients with current or previous HBV infection were examined at the end of treatment. In patients with baseline anti‐HBs positivity, changes in anti‐HBs titre were evaluated. Of 287 patients who met the inclusion criteria, 157 had current (n=4) or previous (n=153) HBV infection; 85 were treated with IFN‐free DAA therapies and 72 were treated with IFN‐based therapies. Six patients experienced HBV reactivation (n=2) or HBV reappearance (n=4) after IFN‐free DAA therapies, while no patient developed HBV reactivation after IFN‐based therapies. The risk factors of HBV reactivation or reappearance were DAA therapies and a reduction in anti‐HBs titre to <12 mIU mL^?1 by the end of treatment. The decline changes of anti‐HBs titre were significantly higher in patients treated with DAA therapies. Although HBV reactivation hepatitis was not observed, three of four patients with HBV reactivation or reappearance after achieving HCV eradication had viremia 8 weeks after completion of therapy. A significant proportion of patients develop HBV reactivation or reappearance without hepatitis after IFN‐free DAA therapies. Low levels of anti‐HBs and their decrease to <12 mIU mL^?1 after treatment are significant risk factors for HBV reactivation or reappearance.     

Sustained virological response with 16‐week glecaprevir/pibrentasvir after failure to sofosbuvir/velpatasvir in post‐transplant severe HCV recurrence in HIV

Direct‐acting antivirals (DAAs) demonstrated high efficacy and safety even in the post‐liver transplant (LT) setting and in HIV‐infected patients, but data are very limited in the early post‐LT period with the most recently available DAA. Two HIV/HCV‐coinfected LT recipients (both grafts from HIV/HCV‐negative donors) experienced early HCV recurrence with severe hepatitis and were treated with sofosbuvir/velpatasvir for 12 weeks. Unfortunately, both patients failed: one (genotype 4d) showed virological breakthrough at week 3 with resistance‐associated substitutions (RASs) for both NS5A and NS5B, while the other (genotype 1a) experienced virological relapse without RAS. Both progressed to fibrosing cholestatic hepatitis and were successfully retreated with glecaprevir/pibrentasvir for 16 weeks achieving sustained virological response. The higher prevalence of RAS in experienced genotype 4 patients and the long time to viral suppression observed in subjects with fibrosing cholestatic hepatitis should be taken into account, considering longer treatment duration to increase the chances of achieving sustained virological response.     

Improved quality of life following direct‐acting antiviral treatment for chronic hepatitis C infection in Rwanda: Results from a clinical trial in sub‐Saharan Africa (the SHARED study)

Around 71 million people are living with chronic hepatitis C virus (HCV) infection, with approximately 14% residing in sub‐Saharan Africa. Direct‐acting antiviral (DAA) therapies offer clear benefits for liver‐related morbidity and mortality, and data from high‐income settings suggest that DAA treatments also provide significant benefits in terms of health‐related quality of life (HRQL). In this study, we assessed the effect of DAA treatment on HRQL for individuals treated for HCV in a clinical trial in Rwanda. We assessed the HRQL of participants using an 83‐question composite survey at Day 0 (‘baseline’) and Week 24 (‘endpoint’). Data were analysed in R. A total of 296 participants were included in this analysis. Their ages ranged from 19 to 90, and 184 (62.2%) were female. There were significant improvements from baseline to endpoint median scores for all physical and mental quality of life sub‐scales. Additionally, a reduction—before and after treatment—in the proportion of those classified as depressed and needing social support was statistically significant (both P < .001). Economic productivity increased after treatment (P < .001), and households classified as food secure increased from baseline to endpoint (P < .001). These results demonstrate that Rwandans with chronic HCV infection experience both clinical and HRQL benefits, including household‐level benefits like substantial gains in workforce stability, economic productivity, and poverty alleviation, from DAA treatment. A stronger demonstration of accurate and broader household‐level benefits achieved through treatment of HCV with DAAs will help financing and investment for HCV in resource‐constrained settings become an urgent priority.     

Current prospects for interferon‐free treatment of hepatitis C in 2012

Present interferon‐based therapy for chronic hepatitis C is limited by both efficacy and tolerability. Telaprevir and boceprevir are the first two direct‐acting antiviral drugs (DAAs) that inhibit hepatitis C virus replication to be licensed for use in conjunction with pegylated interferon and ribavirin. Numerous other DAAs are in clinical development, and phases 2 and 3 trials are evaluating interferon‐free combination DAA therapy. Interferon‐free sustained virologic responses have now been achieved with combinations of asunaprevir and daclatasvir; sofosbuvir and ribavirin; sofosbuvir and daclatasvir; faldaprevir and BI207127; ABT‐450, ritonovir and ABT‐333; ABT‐450, ritonovir and ABT‐072; miracitabine, danoprevir and ritonavir; and alisporivir and ribavirin. Some drugs are genotype‐specific in their activity, whereas others are pan‐genotypic, and differential responses for the genotype 1 subtypes 1a and 1b have emerged with many DAA combinations. Viral breakthrough and resistance are important considerations for future trial design. The prospect of interferon‐free combination DAA therapy for hepatitis C virus is now finally becoming a reality.     

No one size fits all—Shortening duration of therapy with direct‐acting antivirals for hepatitis C genotype 1 infection

The advent of shorter duration, highly effective and well‐tolerated interferon‐free therapy now provides an opportunity for virtually all HCV‐infected individuals to be cured. However, there continues to be a need to simplify and shorten treatment duration. Shortening therapy to 8 weeks with sofosbuvir and ledipasvir can be considered in treatment patients with HCV genotype 1 infection and low baseline viral load. A number of other 8‐week dual and triple therapy direct‐acting antiviral (DAA) regimens are in advanced clinical development. Several small studies have further demonstrated the feasibility of 6 weeks of sofosbuvir therapy in combination with an NS5A inhibitor and a protease inhibitor for HCV genotype 1. Four weeks of therapy with various combinations of the currently available DAAs appears to be suboptimal with poor response rates observed in phase 2 trials. Response‐guided therapy is another promising tool that may allow for shorter therapy but require further research. Shortening therapy and retreating relapsers may be a viable cost‐saving measure, but requires further cost‐benefit analysis and more data on the impact of resistance on retreatment options.     

Adjuvant ribavirin and longer direct‐acting antiviral treatment duration improve sustained virological response among hepatitis C patients at risk of treatment failure

The role of ribavirin (RBV) in the era of direct‐acting antivirals (DAA) is not clear, and DAA studies have been largely genotype‐ and regimen‐specific. Using data from the Chronic Hepatitis Cohort Study, we evaluated the role of RBV and increased DAA treatment duration among patients with chronic hepatitis C (HCV) in routine clinical care. We performed multivariable analysis of data from 4133 patients receiving any of the following: sofosbuvir (SOF); daclatasvir + SOF; grazoprevir + elbasvir; paritaprevir/ritonavir + ombitasvir; simeprevir + SOF; and SOF + ledipasvir; SOF + velpatasvir ± voxilaprevir; and glecaprevir + pibrentasvir—all with/ without RBV. Inverse probability treatment weighting was used to adjust for treatment selection bias. Sustained virological response (SVR) was defined by undetectable HCV RNA 12 weeks after end of therapy. The overall SVR rate was 95%. Mean treatment duration was 12 ± 4.5 weeks. The final model included treatment duration and diabetes, as well as the interaction of RBV with previous treatment status (treatment naïve, interferon treatment failure [TF] or previous DAA TF), cirrhosis status, and HCV genotype (GT). Each one‐month increment of treatment duration increased odds of SVR by 99% (aOR = 1.99). Diabetes, previous DAA TF, and decompensated cirrhosis significantly reduced odds of SVR. RBV significantly increased the likelihood of SVR among patients with decompensated cirrhosis (aOR = 5.05), previous DAA treatment failure (aOR = 5.43), and GT3 (aOR = 13.28). Among RBV‐free regimens, patients with GT3 were less likely to achieve SVR than those with GT1 or 2 (aOR 0.07). Diabetes, decompensated cirrhosis, and prior DAA TF independently reduced the likelihood of SVR. Longer treatment duration increased likelihood of SVR. Conclusion: RBV increased likelihood of SVR among patients with GT3, previous DAA TF, or decompensated cirrhosis.     

A multicenter survey of re‐treatment with pegylated interferon plus ribavirin combination therapy for patients with chronic hepatitis C in Japan

Aim: This study aimed to clarify the factors associated the efficacy of re‐treatment with pegylated interferon (PEG IFN) plus ribavirin combination therapy for patients with chronic hepatitis C who had failed to respond to previous treatment. Methods: One hundred and forty‐three patients who had previously shown relapse (n = 79), non‐response (n = 34) or intolerance (n = 30) to PEG IFN plus ribavirin were re‐treated with PEG IFN plus ribavirin. Results: Twenty‐five patients with intolerance to previous treatment completed re‐treatment and the sustained virological response (SVR) rates were 55% and 80% for hepatitis C virus (HCV) genotype 1 and 2, respectively. On re‐treatment of the 113 patients who completed the previous treatment, the SVR rates were 48% and 63% for genotype 1 and 2, respectively. Relapse after previous treatment and a low baseline HCV RNA level on re‐treatment were associated with SVR in genotype 1 (P < 0.001). Patients with the interleukin‐28B major genotype responded significantly better and earlier to re‐treatment, but the difference in the SVR rate did not reach a significant level between the major and minor genotypes (P = 0.09). Extended treatment of 72 weeks raised the SVR rate among the patients who attained complete early virological response but not rapid virological response with re‐treatment (72 weeks, 73%, 16/22, vs 48 weeks, 38%, 5/13, P < 0.05). Conclusion: Relapse after previous treatment and a low baseline HCV RNA level have predictive values for a favorable response of PEG IFN plus ribavirin re‐treatment for HCV genotype 1 patients. Re‐treatment for 72 weeks may lead to clinical improvement for genotype 1 patients with complete early virological response and without rapid virological response on re‐treatment.     

Memory re‐differentiation and reduced lymphocyte activation in chronic HCV‐infected patients receiving direct‐acting antivirals

Recently, the treatment of HCV has advanced significantly due to the introduction of direct‐acting antivirals (DAAs). Studies using interferon (IFN)‐containing regimens failed to consistently show restoration of immunologic responses. Therefore, IFN‐free DAA formulations provide a unique opportunity to dissect the immunologic effect of HCV cure. This study investigates the restoration of the immune compartment as a consequence of rapid viral clearance in patients successfully treated with DAAs and in the absence of IFN and ribavirin. Here, we evaluate the immunologic changes that occurred following DAA‐mediated HCV cure. Peripheral blood from nineteen previously treatment‐naïve patients with chronic HCV genotype 1a/1b who received an IFN and ribavirin‐free regimen of daclatasvir, asunaprevir and BMS‐791325 was evaluated. Immune reconstitution occurs in patients in whom HCV was successfully eradicated via DAA therapy. Restoration of the CD4⁺ T‐cell compartment in the peripheral blood and a re‐differentiation of the T lymphocyte memory compartment resulted in a more effector memory cell population and a reduction in expression in the co‐inhibitory molecule TIGIT in bulk T lymphocytes. Furthermore, we observed a partial reversal of the exhausted phenotype in HCV‐specific CD8⁺ T cells and a dampening of the activation state in peripheral NK cells. Collectively, our data provide the groundwork for dissecting the effect of DAA therapy on the immune system and identifying novel mechanisms by which chronic HCV infection exerts immunosuppressive effects on T cells through the recently described co‐inhibitory molecule TIGIT.     

Advances in the management of hepatitis C

Significant advances have recently been made in the management of hepatitis C virus (HCV) with many of the changes now part of routine clinical practice. These include the use of non‐invasive methods to assess liver fibrosis, interleukin 28B genotype testing to predict interferon responsiveness and the use of new anti‐viral regimens for HCV genotype 1. Two new antiviral agents (boceprevir and telaprevir) have recently become available in Australia. These protease inhibitors are used in combination with pegylated interferon and ribavirin as triple therapy for genotype 1 HCV. This combination increases sustained virological response from approximately 45–50% to 66–75% in treatment naïve patients. However, these new regimens present novel challenges including complicated treatment algorithms based on virological response, numerous drug interactions and additional side effects especially in patients with advanced fibrosis. The protease inhibitors are the first of many antiviral drugs to become available to treat HCV, heralding the arrival of new agents that will offer greater chances of cure with improved safety and tolerability compared with current therapies.     

Cost‐effectiveness of sofosbuvir for the treatment of chronic hepatitis C‐infected patients

The efficacy of treatment for hepatitis C genotype 1 infection has significantly improved with the introduction of first‐generation protease inhibitors. However, there remains a need for effective treatments for patients infected with other genotypes, for nonresponders and patients unsuitable for interferon. Sofosbuvir is the first nucleotide polymerase inhibitor with pan‐genotypic activity. Sofosbuvir‐based regimens have resulted in >90% sustained virological response across treatment‐naïve genotype 1–6 patients in five phase III clinical trials of sofosbuvir administered with ribavirin or pegylated interferon and ribavirin. This analysis evaluates the cost‐effectiveness of sofosbuvir within the current licensed indication, for genotype 1–6 in the UK. A Markov model followed a cohort of 10 000 patients over lifetime, with approximately 20% initiating treatment for compensated cirrhosis. Sofosbuvir‐regimens were compared to telaprevir, boceprevir, pegylated interferon and ribavirin, or no treatment. Costs and outcomes were discounted at 3.5%. The cost perspective utilized costs applicable to the National Health Service in the UK. Sofosbuvir proved to be cost‐effective in most patient populations with incremental cost‐effectiveness ratios (ICERs) at £11 836/QALY and £7292/QALY against telaprevir and boceprevir, respectively. In genotype 3, sofosbuvir had a weighted ICER of £18 761/QALY. Sofosbuvir‐based regimens are a cost‐effective option for the majority of hepatitis C‐infected patients in the United Kingdom although the incremental cost‐effectiveness varies by genotype and regimen. Sofosbuvir and ribavirin is an alternative regimen for patients unsuitable for interferon.     

Chronic hepatitis C and chronic kidney disease: Advances,limitations and unchartered territories

Over the past few years, treatment options for chronic hepatitis C virus (HCV) infection have evolved dramatically. The current approved interferon‐free direct‐acting antiviral (DAA) regimens have been shown to be safe and effective with sustained virologic response (SVR) rates of >90% in most patients. Unique issues yet remain such as the challenges in patients with impaired renal function or decompensated cirrhosis. Patients with stages 4‐5 chronic kidney disease (CKD) have a higher prevalence of HCV infection compared with the general population. Chronic HCV in those on dialysis and in kidney transplant recipients is associated with higher morbidity and mortality than uninfected patients. The HCV‐infected population is also at risk of developing extrahepatic manifestations associated with altered immune system function and chronic inflammation with cryoglobulinaemic vasculitis being the most common of these manifestations. Therefore, patients with CKD stages 4‐5 have to be considered priority patients for HCV therapy. New antiviral therapies have the potential to improve outcomes in this vulnerable patient population, including those on haemodialysis. Recently published studies conducted in kidney transplant recipients have demonstrated successful outcomes. It is thus essential that we carefully select the most appropriate DAA regimen and the best time for treatment in the context of kidney transplantation or cryoglobulinaemic vasculitis. While sofosbuvir, the only approved nucleotide NS5B inhibitor, has been the backbone of most pangenotypic therapeutic regimens, it has a limitation in those with advanced kidney disease. The currently approved regimens for those with stage 4/5 CKD, while effective, have challenges in that they apply to genotype 1/4 and may require RBV for genotype 1a. Globally, genotype 3 is a common infection, and thus, this group with CKD presents a huge unmet need for effective therapies. As therapy of HCV in renal transplant recipients has been highly successful, it provides an opportunity to expand the use of HCV‐infected organs in solid organ transplantation.     

Augmentation of hepatitis C virus‐specific immunity and sustained virologic response

Treatment for chronic hepatitis C virus (HCV) infection has rapidly evolved into interferon‐free directly acting antiviral regimens (DAA) that result in high sustained virologic response. DAAs primarily work by suppressing HCV replication and rely less on the immune system than interferon‐based therapies. However, it is unclear whether the immune system recovers with suppression of HCV replication and contributes to HCV clearance with DAA therapy. We previously demonstrated HCV clearance is associated with increased HCV‐specific immunity in CHCV‐GT‐1‐infected patients during treatment with sofosbuvir (SOF)+ribavirin (RBV). Here, we aimed to analyse changes in HCV‐specific immunological responses associated with viral clearance with combination DAA therapy of SOF+ledipasvir (LDV) for 12 weeks in CHCV‐GT1 (N=14) patients who relapsed without augmentation of HCV‐specific immunity during treatment with SOF+RBV. Phenotypic and functional changes within the T‐cell compartment of PBMCs pre‐ and post‐treatment were analysed. Retreatment of relapsers with LDV/SOF resulted in all patients attaining SVR₁₂. Suppression of HCV was associated with a decline in T‐cell exhaustion markers (CD57; Tim3; PD1) along with augmented of HCV‐specific T‐cell IFN‐gamma responses post‐treatment. Addition of LDV to SOF was associated with augmentation of HCV‐specific immunity and SVR in patients who previously failed SOF+RBV therapy without increased immunity. These findings demonstrate a novel effect of DAA in inducing host immune responses to aid HCV clearance and achieve SVR.     

Chronic hepatitis C treatment in HIV co‐infection in Portugal: Results from a cohort OF 2133 patients presented by GEPCOI (Portuguese Coinfection Study Group)

Direct‐acting antiviral drugs (DAAs) have recently changed the paradigm of hepatitis C therapy, significantly improving treatment response rates, patient life expectancy and quality of life. In Portugal, sofosbuvir (SOF) and SOF/ledipasvir (SOF/LDV) were fully reimbursed by the National Health System since early 2015 and generalized use of interferon‐free DAA based regimens became current practice. During 2016, the remaining DAAs were sequentially added and covered by the same health access policy. The Portuguese Study Group of Hepatitis and HIV Co‐infection (GEPCOI) collected data from 15 clinical centres in Portugal, pertaining to the HCV treatment experience with DAA regimens. A cohort of 2133 patients was analysed, representing one of the largest DAA treated HCV/HIV co‐infected individuals. The global sustained virologic response (SVR) achieved was 95% in this real‐life cohort setting. Linear regression analysis showed significant differences in treatment response rates when using SOF plus ribavirin (RBV) combination in genotype 2 or 3 infected individuals (P < .002) and in those with liver cirrhosis (P < .002). These findings corroborate that early treatment is mandatory in HIV/HCV co‐infected patients, as response rates may be negatively influenced by higher fibrosis stages and suboptimal DAA regimens. The current national Portuguese health policy should continue to promote wider treatment access and individualized therapy strategies, aiming at the elimination of HCV infection in this high‐risk co‐infected population.     

Role of hepatitis C virus substitutions and interleukin‐28B polymorphism on response to peginterferon plus ribavirin in a prospective study of response‐guided therapy

Recent studies have indicated that amino acid (aa) substitutions in the core region and NS5A interferon sensitivity‐determining region (ISDR) of hepatitis C virus (HCV) as well as genetic polymorphisms in the interleukin‐28B (IL‐28B) locus affect the outcome of interferon (IFN)‐based therapies. We aimed to investigate the role of these factors on response to peginterferon plus ribavirin in a prospective study of response‐guided therapy. The aa sequences in core region and ISDR and rs12979860 genotypes were analysed in 115 HCV‐1 patients. The treatment was 24 weeks for patients achieving a rapid virological response (RVR), 48 weeks for those with an early virological response (EVR) and early terminated in those without an EVR. A sustained virological response (SVR) was achieved in 82% of 34 RVR patients, 45% of 74 EVR patients and 0% of seven non‐EVR patients. Logistic regression analysis showed that ISDR mutation (≥2) [odds ratio(OR): 6.024], double core 70/91 mutations (OR: 0.136), and platelet counts ≥ 15 × 10⁴/μL (OR: 3.119) were independent pretreatment factors associated with SVR. Apart from rs12979860 CC genotype, low viral load and ISDR mutation (≥2) were significant factors predictive of RVR. Combination of rs12979860 genotype and baseline viral characteristics (viral load and core/ISDR mutations) could predict RVR and SVR with positive predictive value of 100% and 91%, and negative predictive value of 80% and 54%, respectively. In conclusion, pretreatment screening rs12979860 genotype and aa substitutions in the core region and ISDR could help identifying patients who are good candidates for peginterferon plus ribavirin therapy.     

Outcome of cutaneous psoriasis in hepatitis C virus‐infected patients treated with Direct‐Acting Antiviral therapy

Apart from chronic liver disease, hepatitis C virus (HCV) may be responsible for several extra‐hepatic manifestations. Its involvement in psoriasis development is still controversial. The aim of this study was to evaluate the possible effect of anti‐HCV direct‐acting antiviral (DAA) treatment on cutaneous psoriasis. Thirty‐seven consecutive HCV patients with cutaneous psoriasis underwent efficacious DAA treatment, and all of them were efficiently cured as shown by HCV RNA negativity 24 weeks after stopping therapy (PT24W). An expert dermatologist evaluated the skin lesions at baseline, end of treatment (EOT) and PT24W using the psoriasis area severity index (PASI) scoring system. The impact on quality of life was measured with the Dermatologic Quality of Life Index (DLQI). Six patients had a stable disease throughout the study period, whereas 31/37 patients (83.8%) showed a significant improvement of the skin lesions at EOT (P < .0001). However, 24 of these 31 patients (77.4%) had a dramatic worsening of the psoriatic lesions at PT24W compared with EOT (P < .001), with lesion severity comparable to baseline. The outcome of psoriasis during and after treatment was independent of baseline PASI score, age, sex, HCV genotype, liver disease stage and of the presence of arterial hypertension, diabetes and autoimmune diseases. In conclusion, DAA‐based HCV cure has only a transient effect on skin lesions of patients with concomitant cutaneous psoriasis.     

Antiviral treatment of hepatitis C virus infection and factors affecting efficacy

Hepatitis C virus(HCV)infection is the leading cause of chronic liver-related diseases,including cirrhosis,liver failure,and hepatocellular carcinoma.Currently,no effective vaccine is available for HCV infection.Polyethylene glycol interferon-α(PegIFN-α)in combination with ribavirin(RBV)is the standard of care(SOC)for chronic hepatitis C.However,the efficacy of PegIFN-αand RBV combination therapy is less than 50%for genotype 1HCV,which is the dominant virus in humans.In addition,IFN and RBV have several severe side effects.Therefore,strategies to improve sustained virological response(SVR)rates have been an important focus for clinical physicians.The serine protease inhibitors telaprevir and boceprevir were approved by the United States Food and Drug Administration in 2011.The addition of HCV protease inhibitors to the SOC has significantly improved the efficacy of treatments for HCV infection.Several direct-acting antiviral drugs currently in late-stage clinical trials,both with and without pegIFN and RBV,have several advantages over the previous SOC,including higher specificity and efficacy,fewer side effects,and the ability to be administered orally,and might be optimal regimens in the future.Factors affecting the efficacy of anti-HCV treatments based on IFN-αinclude the HCV genotype,baseline viral load,virological response during treatment,host IL28B gene polymorphisms and hepatic steatosis.However,determining the effect of the above factors on DAA therapy is necessary.In this review,we summarize the development of antiHCV agents and assess the main factors affecting the efficacy of antiviral treatments.