Impact of IL28B polymorphisms on 24-week telaprevir-based combination therapy for Asian chronic hepatitis C patients with hepatitis C virus genotype 1b

In search of a function for human type III interferons: insights from inherited and acquired deficits

The essential and redundant functions of human type I and II interferons (IFNs) have been delineated over the last three decades by studies of patients with inborn errors of immunity or their autoimmune phenocopies, but much less is known about type III IFNs. Patients with cells that do not respond to type III IFNs due to inherited IL10RB deficiency display no overt viral disease, and their inflammatory disease phenotypes can be explained by defective signaling via other interleukine10RB-dependent pathways. Moreover, patients with inherited deficiencies of interferon-stimulated gene factor 3 (ISGF-3) (STAT1, STAT2, IRF9) present viral diseases also seen in patients with inherited deficiencies of the type I IFN receptor (IFNAR1/2). Finally, patients with autoantibodies neutralizing type III IFNs have no obvious predisposition to viral disease. Current findings thus suggest that type III IFNs are largely redundant in humans. The essential functions of human type III IFNs, particularly in antiviral defenses, remain to be discovered.

Human genetics of HCV infection phenotypes in the era of direct-acting antivirals

The recent introduction of direct-acting antivirals (DAAs) has revolutionized hepatitis C virus (HCV) therapy by improving virus eradication rates to over 90% in most patient groups. However, the impact of DAAs on global disease burden is currently limited, and a large number of chronically infected individuals remain at risk of developing liver complications, such as liver cirrhosis and hepatocellular carcinoma (HCC). The identification of patients at risk of liver complications and a greater understanding of the biological mechanisms involved in HCV disease progression might improve disease control. Recent genome-wide association and exome sequencing studies have identified several host genetic variants influencing the progression of liver fibrosis and the development of HCC associated with HCV infection and are reviewed here. Interestingly, some of the genetic variants associated with those HCV-associated liver complications were also associated with the clinical course of non-viral chronic hepatitis. Future challenges include the incorporation of this genetic information into clinical risk models for personalized disease management and the study of emerging phenotypes such as liver fibrosis regression and HCC development after HCV eradication.

Is the conquest of Hepatitis C imminent?

Hepatitis C virus represents a global pathogen of human health significance. In the space of less than three decades, we have witnessed the discovery of the virus, a growing understanding of the structure and biology of the viral-encoded proteins and their interaction with the host cell and the sequencing of the viral genome. Most importantly, we have moved from early therapeutic strategies aimed at crude boosting of host anti-viral immunity, limited by side effects and with poor response rates, to therapies that directly exploit our understanding of viral biology. In this review, we discuss the significance of the virus, its' discovery and outline the advances in the molecular characterisation of the virus, before setting these within the context of contemporary and emerging therapeutic strategies as well as viral resistance mechanisms.

Pretreatment serum levels of interferon-gamma-inducible protein-10 are associated with virologic response to telaprevir-based therapy

AIM

Telaprevir (TVR) remarkably improves the efficacy of interferon treatment for chronic hepatitis C. Interleukin-28B (IL28B) genotype and interferon-gamma-inducible protein-10 (IP-10) level predict virologic response to peg-interferon (Peg-IFN)/ribavirin (RBV) therapy. We aimed to investigate the usefulness of pretreatment serum IP-10 levels and IL28B genotyping in predicting sustained virologic response (SVR) to TVR-based triple therapy.

METHODS

In this multi-center study, patients infected with hepatitis C virus genotype 1 with high viral load (⩾5.0logIU/mL) were treated with TVR for 12weeks and Peg-IFN/RBV for 24weeks in Japan. IL28B genotype, serum IP-10 levels, other clinical parameters, and drug dosages were assessed before treatment.

RESULTS

We included 121 patients who were treated with TVR for at least 8weeks and Peg-IFN/RBV for 24weeks. The median IP-10 levels were significantly lower in rapid virologic response (RVR) or SVR in the IL28B non-TT genotype group, with no significant difference in the TT genotype group. RVR rates were significantly lower in the group with higher serum IP-10 levels (>450pg/mL). In the non-TT IL28B genotype group, RVR and SVR rates were significantly lower in the group with higher IP-10 levels. SVR rates in the group with lower IP-10 levels (<450pg/mL) increased to 82% for those showing RVR, but reduced to 27% in the group with higher IP-10 levels for those not showing RVR.

CONCLUSIONS

Determination of serum IP-10 levels before treatment could be useful for predicting favorable virologic response to TVR-based triple therapy, especially in patients with IL28B non-TT genotype.

Effect of native vitamin D3 supplementation on refractory chronic hepatitis C patients in simeprevir with pegylated interferon/ribavirin

AIM

Protease inhibitors with pegylated interferon (PEG IFN)/ribavirin improve a sustained virological response (SVR) rate to approximately 90% in chronic hepatitis C genotype 1b patients with IL28B rs8099917 genotype TT, but yield only approximately 50% in those with the unfavorable non-TT. Among such treatment-refractory patients, serum vitamin D levels could influence the SVR rate. This randomized controlled trial was conducted to assess the effect of native vitamin D supplementation in simeprevir with PEG IFN/ribavirin for 1b patients with non-TT.

METHODS

Patients were randomly assigned to receive simeprevir (100 mg/day) for 12 weeks plus PEG IFN/ribavirin for 24 weeks (control group, n = 58), or vitamin D (2000 IU/day) for 16 weeks including a lead-in phase plus PEG IFN/ribavirin for 24 weeks (vitamin D group, n = 57). The primary end-point was sustainably undetectable viremia 24 weeks after the end of treatment (SVR).

RESULTS

SVR rates were 37.9% in the control group and 70.2% in the vitamin D group. In subgroup analysis, SVR rates of prior null responders were 11.8% and 54.5%, respectively. SVR rates for advanced fibrosis were 28.6% and 65.4%. SVR rates for patients with vitamin D3 deficiency at the baseline were 25.0% in the control group and 66.7% in the vitamin D group. Overall, the SVR rate was significantly higher in patients with high serum 25(OH)D3 levels at the beginning of combination therapy than in those with low serum 25(OH)D3 levels.

CONCLUSION

Native vitamin D3 supplementation improved SVR rates in simeprevir with PEG IFN/ribavirin for chronic hepatitis C genotype 1b patients with refractory factors.

Evaluation of factors associated with relapse in telaprevir-based triple therapy for chronic hepatitis C

BACKGROUND AND RATIONALE

Most patients with chronic hepatitis C show virological response to telaprevir-based triple therapy, and achieve an end-of-treatment response (ETR). However, some patients showing ETR develop virological relapse. This study was carried out to evaluate factors associated with relapse after triple therapy.

MATERIALS AND METHODS

A prospective, multicentric study was conducted in chronic hepatitis C patients who received telaprevir-based triple therapy. We evaluated independent variables such as age, with or without cirrhosis, prior treatment response to interferon (IFN) therapy, IL28B genotype, core amino acid (aa) 70 mutation, drug adherence, white blood cell counts, hemoglobin level, and serum low-density lipoprotein (LDL) cholesterol level. The characteristics of the patients who relapsed after achieving ETR were compared with those who did not.

RESULTS

Among 168 patients, 157 patients achieved ETR (93.5%) and 11 discontinued. Of these 157 patients, relapse occurred in 21 patients (13.4%). Nineteen patients (90.5%) of 21 relapsed patients had the IL28B non-TT genotype (P = 1.79 × 10 -9 ). Multivariate analysis identified core amino acid 70 [P = 0.018, crude odds ratio (OR): 6.927] and the IL28B genotype (P = 3.758 × 10 -5 , crude OR: 39.311) as significantly independent factors that influenced the relapse-related variables. Among the 49 patients with the IL28B non-TT, 18 patients had core aa70 mutation and 31 patients had core aa70 wild-type. In addition, 66.7% (12/18) of those with core aa70 mutation and 22.6% (7/31) of those with core aa70 wild-type developed relapse (P = 0.005).

DISCUSSION

Core aa70 mutation and the IL28B non-TT genotype were identified as independent factors that influenced relapse after achievement of ETR for telaprevir-based triple therapy.

Impact of IL28B, APOH and ITPA Polymorphisms on Efficacy and Safety of TVR- or BOC-Based Triple Therapy in Treatment-Experienced HCV-1 Patients with Compensated Cirrhosis from the ANRS CO20-CUPIC Study

BACKGROUND

Human genetic factors influence the outcome of pegylated interferon and ribavirin hepatitis C therapy. We explored the role of IL28B, APOH and ITPA SNPs on the outcomes of triple therapy including telaprevir or boceprevir in patients with compensated cirrhosis chronically infected with HCV-1.

PATIENTS AND METHODS

A total of 256 HCV-1 Caucasian treatment-experienced patients with compensated cirrhosis from the ANRS CO20-CUPIC cohort were genotyped for a total of 10 candidate SNPs in IL28B (rs12979860 and rs368234815), APOH (rs8178822, rs12944940, rs10048158, rs52797880, rs1801689 and rs1801690) and ITPA (rs1127354 and rs7270101). We tested the association of IL28B and APOH SNPs with sustained virological response and of ITPA SNPs with anemia related phenotypes by means of logistic regression assuming an additive genetic model.

RESULTS

None of the six APOH SNPs were associated with sustained virological response. The favorable alleles of the IL28B SNPs rs12979860 and rs368234815 were associated with sustained virological response (rs12979860: OR = 2.35[1.50-3.70], P = 2x10(-4)). Refined analysis showed that the effect of IL28B SNPs on sustained virological response was restricted to prior PegIFN/RBV relapse (OR = 3.80[1.82-8.92], P = 8x10(-4)). We also confirmed the association between ITPA low activity alleles and protection against early hemoglobin decline in triple therapy (P = 2x10(-5)).

CONCLUSION

Our results suggest that the screening of rs12979860 may remain interesting for decision making in prior relapse HCV-1 Caucasian patients with compensated cirrhosis eligible for a telaprevir- or boceprevir-based therapy.

Effectiveness of triple therapy with simeprevir for chronic hepatitis C genotype 1b patients with prior telaprevir failure

Favourable efficacy and safety profiles for simeprevir in combination with pegylated interferon alpha (PEG-IFNα) and ribavirin (triple therapy) have been shown in clinical trials. This study was carried out to evaluate the effectiveness of simeprevir-based triple therapy for patients with prior telaprevir treatment failure. This multicentre, observational cohort consisted of 345 consecutive Japanese patients infected with HCV genotype 1b, including 20 who had experienced telaprevir-based triple therapy. Amino acid substitutions in the NS3/4A region were identified by direct sequencing at the time of relapse or breakthrough in treatment with telaprevir and at the initiation of treatment with simeprevir. Patients were stratified according to prior response to PEG-IFNα and ribavirin. Of the 20 patients with telaprevir treatment failure, 10 (50.0%) achieved sustained virological response at week 12 after the end of treatment (SVR12). For patients treatment naïve [3/4 (75.0%)] or with prior relapse [1/1 (100%)] or partial response [5/6 (83.3%)] to PEG-IFNα and ribavirin, almost all achieved SVR12, mainly because of the improvement of treatment adherence, especially to direct-acting antiviral agent and ribavirin. However, of the nine patients with prior null response to PEG-IFNα and ribavirin, only one (11.1%) achieved SVR12, despite all having received an adequate treatment dosage, and five (55.6%) achieved rapid virological response. The treatment outcome of simeprevir-based triple therapy for HCV genotype 1b patients with prior telaprevir failure depended on the prior response to PEG-IFNα and ribavirin. For patients with prior null response to PEG-IFNα and ribavirin, retreatment with simeprevir-based triple therapy is not a useful option.

Vitamin D-related gene polymorphisms do not influence the outcome and serum vitamin D level in pegylated interferon/ribavirin therapy combined with protease inhibitor for patients with genotype 1b chronic hepatitis C

Although several vitamin D-related gene polymorphisms were reported to affect the outcome of pegylated interferon/ribavirin (PR) therapy in chronic hepatitis C patients, there are no reports on the impact of the vitamin D-related gene polymorphisms in PR therapy combined with protease inhibitor (PI). Vitamin D-related gene polymorphisms were determined in 177 genotype 1b-infected chronic hepatitis C patients who received 12 weeks of PR therapy with telaprevir, a first-generation PI, followed by 12 weeks of PR therapy. The sustained virologic response (SVR) rate was 83.1% (147 of 177 patients). The frequencies of vitamin D-related gene polymorphisms were: 83 non-TT and 94 TT genotypes for GC, 97 non-AA and 80 AA genotypes for DHCR7, 151 non-AA and 26 AA genotypes for CYP2R1, 162 non-GG and 15 GG genotypes for CYP27B1, and 105 non-GG and 72 GG genotypes for VDR gene. Multivariate analysis extracted IL28B TT genotype (P = 2.05 × 10(-6)) and serum 25(OH) D3 level (P = 0.024) as independent factors contributing to the achieving of SVR. The SVR rate in IL28B TT genotype patients with serum 25(OH) D3 level of < 25 ng/ml was significantly low compared to other patients. None of the vitamin D-related gene polymorphisms affected the treatment outcome and serum 25(OH) D3 level. In conclusions, the IL28B polymorphism and serum 25(OH) D3 level contributed significantly and independently to SVR in PR combined with PI for genotype 1b-infected chronic hepatitis C patients. However, none of vitamin D-related gene polymorphisms had an impact on the treatment outcome and serum 25(OH) D3 level.

Factors associated with sustained virological response in 24-week telaprevir-based triple therapy for chronic hepatitis C genotype 1b patients with the IL28B minor genotype

AIM

Single nucleotide polymorphisms (SNP) near the interleukin-28B (IL28B) gene affect the outcome of 24-week telaprevir-based triple therapy with telaprevir, pegylated interferon-α and ribavirin for chronic hepatitis C virus (HCV) genotype 1b patients. We aimed to identify factors associated with treatment outcomes in patients with the unfavorable minor IL28B SNP genotype, who have poor response to combination therapy.

METHODS

Pretreatment and on-treatment factors associated with sustained virological response (SVR) for 24-week telaprevir-based triple therapy were analyzed using multiple logistic regression analysis in 106 HCV genotype 1b patients with the minor IL28B SNP rs8099917 genotype (non-TT).

RESULTS

Of the 106 non-TT patients, 62 (58.5%) achieved SVR. Of the 44 remaining patients, 22 experienced relapse, 13 experienced viral breakthrough and nine were non-responders. Pretreatment factors such as treatment-naïve/prior treatment response (P = 0.0041), high fasting serum low-density lipoprotein cholesterol (LDL-C) concentration (P = 0.0068) and low serum HCV RNA levels (P = 0.0088) were significantly and independently associated with SVR. On-treatment factors such as achievement of rapid virological response (RVR) were significantly and independently associated with SVR (P = 0.0001). For both pre- and on-treatment factors, treatment-naïve/prior treatment response (P = 0.0018), low pretreatment serum fasting LDL-C (P = 0.0062) and achieving RVR (P = 0.0021) were significantly and independently associated with SVR.

CONCLUSION

In HCV genotype 1b patients with the minor IL28B SNP rs8099917 genotype, evaluating prior treatment response and achieving RVR and pretreatment serum fasting LDL-C concentrations were useful for predicting SVR achievement after 24-week telaprevir-based triple therapy.

Innate and adaptive genetic pathways in HCV infection

Infection with hepatitis C virus (HCV) leads to a wide spectrum of clinical manifestations. This heterogeneity is underpinned by the host immune response and the genetic factors that govern it. Polymorphisms affecting both the innate and adaptive immunity determine the outcome of exposure. However the innate immune system appears to play a greater role in determining treatment-associated responses. Overall the effects of IFNL3/4 appear dominant over other polymorphic genes. Understanding how host genetics determines the disease phenotype has not been as intensively studied. This review summarizes our current understanding of innate and adaptive immunogenetic factors in the outcome of HCV infection. It focuses on how they relate to resolution and the progression of HCV-related liver disease, in the context of current and future treatment regimes.

Safety and efficacy of partial splenic embolization in telaprevir-based triple therapy for chronic hepatitis C

OBJECTIVE

Pegylated-interferon/ribavirin (peg-IFN/RBV) therapy with a protease inhibitor is the standard therapy for genotype 1b chronic hepatitis C. Despite improving treatment outcomes, patients with thrombocytopenia are often difficult to treat because interferon commonly exacerbates thrombocytopenia. In this study, partial splenic embolization (PSE) was performed in patients with hypersplenism-induced thrombocytopenia to determine the effectiveness of this method as a potential treatment.

METHODS

Patients were pretreated with PSE and then received triple combination therapy. The safety and efficacy of PSE was evaluated.

RESULTS

Eighteen patients were analyzed, including 12 patients with the interleukin 28B (IL28B) major genotype and 12 patients with the inosine triphosphatase (ITPA) major genotype. The median embolization rate with PSE was 70% (range: 40-85%). PSE increased the patients' platelet counts from 71.5×10(3) /μL (53-99×10(3) /μL) to 121.5×10(3) /μL (70-194×10(3) /μL; p=0.0002). The patients' platelet counts fluctuated above 50×10(3) /μL during the treatment. Specifically, the increase in the platelet count was significantly associated with the ITPA major genotype compared with the minor genotype (p=0.0057 at 2 weeks, p=0.0031 at 3 weeks, and p=0.0148 at 4 weeks). Adherence to peg-IFN-α2b was sufficient (1.38 μg/kg/week). The rapid viral response rate was 72.2% (13/18), the end of treatment response rate was 88.9% (16/18), and the sustained virological response (SVR) rate was 66.7% (12/18). The SVR rate for patients with the IL28B major genotype was 83.3% (10/12). No adverse effect due to PSE pretreatment was found in any patients. Furthermore, no patient discontinued treatment due to thrombocytopenia.

CONCLUSION

PSE, in conjunction with triple combination therapy, is a useful and safe method to treat genotype 1b chronic hepatitis C patients with hypersplenism-induced thrombocytopenia.

A 48-week telaprevir-based triple combination therapy improves sustained virological response rate in previous non-responders to peginterferon and ribavirin with genotype 1b chronic hepatitis C: A multicenter study

AIM

The sustained virological response (SVR) rate of non-responders to peginterferon and ribavirin therapy (PR) is low for 24-week telaprevir-based triple combination therapy (T12PR24), compared to that of treatment-naïve patients or previous-treatment relapsers. This study investigated which characteristics of non-responders were associated with a better SVR rate to 48-week therapy (T12PR48).

METHODS

A total of 103 Japanese non-responders with genotype 1b chronic hepatitis C received telaprevir-based therapy. Among them, 81 patients (50 partial and 31 null responders) received T12PR24 and 22 (seven partial and 15 null responders) who agreed to the extended therapy received T12PR48.

RESULTS

Multivariate logistic regression analysis for SVR identified the interleukin-28B (IL28B) rs8099917 TT genotype (P = 0.0005, odds ratio [OR] = 10.38), extended rapid virological response (P = 0.0008, OR = 7.02), T12PR48 regimen (P = 0.0016, OR = 9.31) and previous partial responders (P = 0.0022, OR = 5.89). Among partial responders, the SVR rate did not differ significantly between T12PR48 (85.7%) and T12PR24 (70.0%). Among null responders, the SVR rate was significantly higher with T12PR48 than T12PR24 (66.7% vs 22.6%, P = 0.0037). Among patients with the IL28B non-TT genotype, the SVR rate was significantly higher with T12PR48 than T12PR24 (68.8% vs 37.7%, P = 0.0288). Moreover, among null responders with the non-TT genotype, the SVR rate was significantly higher with T12PR48 than T12PR24 (66.7% vs 9.1%, P = 0.0009).

CONCLUSION

T12PR48 improves the SVR rate in null responders, patients with the non-TT genotype, and null responders with a non-TT genotype.

Relationship between HCV dynamics and sustained virological responses in chronic hepatitis C genotype 1b patients treated with telaprevir-based triple therapy

OBJECTIVES

This study investigated the relationship between hepatitis C virus (HCV) dynamics and sustained virological response (SVR), as well as the efficacy of an extended treatment with telaprevir-based triple therapy among patients with chronic hepatitis C genotype 1b.

METHODS

Among 220 patients receiving triple therapy for 24 weeks, the SVR rate was analyzed at each time point at which HCV RNA became undetectable. The SVR rates in the patients who did not achieve a rapid virological response (RVR) were compared with those in 27 patients who received triple therapy for 48 weeks.

RESULTS

The SVR rates of interleukin 28B (IL28B) TT and non-TT patients were 100 versus 66.7% after 1 week, 97.6 versus 72.2% after 2 weeks, 95.2 versus 84.2% after 3 weeks, 93.1 versus 72.2% after 4 weeks, 76.9% versus 11.1% after 6 weeks, and 88.9 versus 14.3% after 8 weeks, respectively. All of the IL28B TT patients who showed undetectable HCV RNA levels until week 8 achieved an SVR. In contrast, the SVR rates in the IL28B non-TT patients who did not achieve RVR with 24 and 48 weeks of treatment were 11.8 and 62.5%, respectively (P=0.017).

CONCLUSION

These results suggest that an SVR can frequently be achieved by IL28B TT patients, even with 24 weeks of treatment, when HCV RNA remains undetectable until week 8, and also that IL28B non-TT patients should have RVR values to achieve an SVR with 24 weeks of treatment. The SVR rate was low in IL28B non-TT patients treated for 24 weeks who did not achieve an RVR; however, it could increase when the treatment duration was extended to 48 weeks.

Baseline factors and very early viral response (week 1) for predicting sustained virological response in telaprevir-based triple combination therapy for Japanese genotype 1b chronic hepatitis C patients: a multicenter study

BACKGROUND

Genetic polymorphisms near Interleukin 28B (IL28B) (rs8099917) and a rapid virological response (RVR) have been reported as predictors for a sustained virological response (SVR) to telaprevir (TVR)-based triple combination therapy. However, the association between SVR and viral kinetics earlier than week 4 after initiation of therapy remains unclear. Thus, we evaluated the SVR prediction ability of baseline factors and reduced hepatitis C virus (HCV) RNA levels at week 1 after the initiation of TVR-based therapy in Japanese genotype-1b chronic hepatitis C (CHC) patients.

METHODS

A total of 156 Japanese CHC patients received a 24-week regimen of TVR-based therapy. Baseline factors and reduction in HCV RNA levels at weeks 1 and 4 after the initiation of therapy were analyzed for SVR prediction.

RESULTS

Multiple logistic regression analysis for SVR in TVR-based therapy identified the IL28B TT genotype, a reduction of ≥ 4.7 log10 IU/mL in HCV RNA levels at week 1, RVR, and treatment-naïve/relapse. Whereas the SVR rate was higher than 90 % regardless of the reduction in HCV RNA levels at week 1 in patients with the TT genotype, a reduction of ≥ 4.7 log10 IU/mL in HCV RNA levels at week 1 was the strongest predictor of SVR in patients with the non-TT genotype, as determined by multiple logistic regression analysis (P = 0.0043).

CONCLUSIONS

The IL28B TT genotype is the most important baseline factor for predicting SVR, and a ≥ 4.7 log10 IU/mL reduction in HCV RNA at week 1 is a useful very early on-treatment predictor of SVR, especially in the non-TT genotype.

Prediction of Sustained Virological Response to Telaprevir-Based Triple Therapy Using Viral Response within 2 Weeks

The aim of the present study was to predict sustained virological response (SVR) to telaprevir with pegylated interferon (PEG-IFN) and ribavirin using viral response within 2 weeks after therapy initiation. Thirty-six patients with genotype 1 hepatitis C virus (HCV) and high viral load were treated by telaprevir-based triple therapy. SVR was achieved in 72% (26/36) of patients. Significant differences between the SVR group and non-SVR group were noted regarding response to prior PEG-IFN plus ribavirin, interleukin (IL)28B polymorphism, amino acid substitution at core 70, cirrhosis, hyaluronic acid level, and HCV-RNA reduction within 2 weeks. Setting 4.56 logIU/mL as the cut-off value for HCV-RNA reduction at 2 weeks, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for predicting SVR were 77%, 86%, 95%, 50%, and 79%, respectively, and for neither the IL28B minor allele nor core 70 mutant were 80%, 71%, 91%, 50%, and 78%, respectively. In conclusion, evaluation of viral reduction at 2 weeks or the combination of IL28B polymorphism and amino acid substitution at core 70 are useful for predicting SVR to telaprevir with PEG-IFN and ribavirin therapy.

Serum 25(OH)D3 levels affect treatment outcomes for telaprevir/peg-interferon/ribavirin combination therapy in genotype 1b chronic hepatitis C

BACKGROUND

Close relationships between chronic hepatitis C and vitamin D levels have been reported. For genotype 1b infection, the current standard of care is pegylated interferon/ribavirin therapy combined with a protease inhibitor. The present study analyzed the relationship between outcomes of triple therapy and serum 25(OH)D3 levels.

METHODS

Factors contributing to sustained virological response were investigated in 177 patients with chronic hepatitis C who received telaprevir-based triple therapy in this prospective study.

RESULTS

The sustained virological response rate was 86.9% in patients with 25(OH)D3 levels of >18 ng/ml; this was higher than the 66.7% in patients with 25(OH)D3 levels of ≤ 18 ng/ml (P=0.003). 25(OH)D3 levels and IL28B genotype were identified as significantly independent factors contributing to sustained virological response. The sustained virological response rate did not differ according to 25(OH)D3 levels in patients with the IL28B major genotype. The sustained virological response rate was 64.9% in patients with the IL28B minor genotype and 25(OH)D3 levels of >18 ng/ml, and was 38.5% in those with decreased 25(OH)D3 levels (P=0.045).

CONCLUSIONS

In triple therapy, 25(OH)D3 levels were an independent factor contributing to sustained virological response. Of particular note, the sustained virological response rate was significantly lower in patients with the IL28B minor genotype.

Nanomedicines in the treatment of hepatitis C virus infection in Asian patients: optimizing use of peginterferon alfa

Asia is endemic for hepatitis C virus (HCV) infection, which is the leading cause of cirrhosis, hepatic decompensation, hepatocellular carcinoma, and liver transplantation worldwide. HCV has six major genotypes and each HCV genotype has its specific geographic distribution. HCV genotypes 1, 2, 3, and 6 are common in Asia. The aim of HCV treatment is to eradicate the virus by effective therapeutic agents; viral clearance is durable after long-term post-treatment follow-up. In most Asian countries, peginterferon alfa (PEG-IFN α) in combination with ribavirin remains the standard of care, and the overall sustained viral response (SVR) rate in Asian HCV patients is higher than that in Western patients. The differences are most significant in patients with HCV genotype 1 (HCV-1) infection, which is attributed to the higher frequency of IFN-responsive or favorable interleukin-28B (IL-28B) genotype in Asian populations than in other ethnic populations. In addition, the introduction of response-guided therapy, where the optimized treatment duration is based on the early viral kinetics during the first 12 weeks of treatment, increases the SVR rate. Recently, telaprevir or boceprevir-based triple therapy was found to further improve the SVR rate in treated and untreated HCV-1 patients and has become the new standard of care in Western and some Asian countries. Many novel direct-acting antiviral agents, either in combination with PEG-IFN α plus ribavirin or used as IFN-free regimens are under active investigation. At the time of this writing, simeprevir and sofosbuvir have been approved in the US. Because the SVR rates in Asian HCV patients receiving PEG-IFN α plus ribavirin therapy are high, health care providers should judiciously determine the clinical usefulness of these novel agents on the basis of treatment duration, anticipated viral responses, patient tolerance, financial burdens, and drug accessibility.

Direct-acting Antiviral Agents for the Treatment of Chronic Hepatitis C Virus Infection

Hepatitis C virus (HCV) is a leading cause of cirrhosis and hepatocellular carcinoma (HCC) in the US and Japan. Therefore, eradication of HCV may reduce the occurrence of HCC in HCV-infected individuals. In 2011, the use of first-generation HCV NS3/4A protease inhibitors such as telaprevir and boceprevir was initiated for clinical treatment of HCV. Administration of telaprevir and boceprevir plus peginterferon and ribavirin increased rates of sustained virological response (SVR) in HCV genotype 1-infected patients. However, this treatment regimen also led to severe adverse events. Second-generation direct-acting antiviral agents (DAAs) for HCV, such as simeprevir plus peg-interferon and ribavirin also resulted in higher SVR rates, with similar adverse events to other peg-interferon and ribavirin treatments. Higher SVR rates in HCV genotype 1- and 2-infected patients were achieved with 12-16 weeks of sofosbuvir plus other class DAAs with/without ribavirin and 12 weeks of sofosbuvir plus ribavirin, respectively. For "difficult-to-treat" HCV-infected patients, more therapeutic options are needed. Further studies examining the efficacy and adverse effects of such therapies will be required for the development of additional treatments.