Clinical milestones for the prediction of severe anemia by chronic hepatitis C patients receiving telaprevir-based triple therapy

Impact of ITPA gene polymorphism for predicting anemia and treatment outcome in HCV infected patients taking Sofosbuvir Ribavirin therapy

BACKGROUND

Globally, 80 million people are suffering from chronic Hepatitis C virus (HCV) infection. Sofosbuvir ribavirin-based anti-HCV therapy is associated with anemia and other adverse effects. Polymorphisms of Inosine triphosphatase (ITPA) gene may cause functional impairment in the Inosine triphosphate pyrophosphatase enzyme, resulting in enhanced sustained viral response (SVR) and protection from ribavirin-associated anemia in patients on therapy. The study objective was to investigate the effect of Inosine triphosphatase gene polymorphism on SVR achievement, hemoglobin decline and ribavirin dose reduction in patients on therapy.

METHODS

This prospective cohort study was of 170 hepatitis C infected patients received 6-month sofosbuvir ribavirin therapy. Patient viral load, reduction in ribavirin amount, liver function test, and complete blood count were noted monthly. Inosine triphosphatase variants rs1127354 and rs7270101 were assessed through the restriction fragment length polymorphism and confirmed using Sanger sequencing. The impact of polymorphism on cumulative reduction of ribavirin, and anti-HCV therapy outcome were studied.

RESULTS

A total of 74.3% of patients had ITPA rs1127354 CC genotype, 25.7% were CA and AA 0%. The frequency of ITPA genotype rs7270101-AA was 95%, AC 5%, and CC was 0%. ITPA rs1127354-CA had a notably positive impact on SVR achievement with a zero-relapse rate. ITPA rs1127354-CA genotype was significantly (P ˂0.05) protective against ≥ 2 g/dl Hb reduction from baseline to 1st, 2nd and 6th months of therapy. During treatment, Hb reduction ≥ 10 g/dl was frequently observed in rs1127354-CC genotype and rs7270101-AA genotype patients. Ribavirin dose reduction was significantly (P ˂0.05) high in rs1127354-CC genotype as compared to genotype CA whereas no significant difference was observed in ribavirin dose reduction in rs7270101 AA and non-AA genotype. Patient baseline characteristics such as age, body mass index, rs1127354-CC genotype, and baseline Hb were significantly associated with significant Hb reduction.

CONCLUSION

Pretreatment evaluation of ITPA polymorphism can be a diagnostic tool to find out patients at risk of anemia and improve treatment adherence. ITPA genotype rs1127354-CA contributes to improved compliance with ribavirin dose and protects against hemoglobin decline in HCV patients while taking ribavirin-based therapy. However, ITPA rs1127354, rs7270101 polymorphism have no significant impact on SVR achievement.

Association between inosine triphosphatase rs1127354 polymorphisms and ribavirin-induced anaemia and outcome in hepatitis C virus-infected patients: A meta-analysis

WHAT IS KNOWN AND OBJECTIVES

The association between inosine triphosphatase (ITPA) rs1127354 polymorphisms in HCV-infected patients receiving ribavirin (RBV)-based therapy, and the risk of adverse drug reaction and outcomes is still unclear. A meta-analysis was conducted to summarize and clarify this association systematically.

METHODS

A comprehensive search was performed in PubMed, Embase and Web of Sciences, and twenty-two studies were selected from the literature search. Pooled odds ratio (OR) and 95% confidence interval (95% CI) were estimated by either fixed- or random-effects models.

RESULTS

Four outcomes were evaluated: (a) haemoglobin decline: significant associations with haemoglobin decline were found for rs1127354 CC VS CA + AA (OR = 10.59, 95% CI = 6.39-17.54); (b) severe anaemia: significant association with severe anaemia was observed for rs1127354 CC VS CA + AA (OR = 16.24, 95% CI = 6.21-42.43); (c) sustained virological response (SVR): CC genotype carriers had a decrease SVR during treatment (OR = 0.65, 95% CI = 0.52-0.81); (d) RBV dose reduction or stopping treatment: although statistical evidence of an association was found between the polymorphism and RBV dose reduction during treatment (OR = 1.80, 95% CI = 1.03-3.13), the sensitivity analysis suggested this result was not robust.

WHAT IS NEW AND CONCLUSION

Patients with ITPA rs1127354 CC polymorphism are more likely to develop haemolytic anaemia, severe anaemia and decreased SVR. Testing for this genetic polymorphism may benefit patients.

Effectiveness and safety of daclatasvir plus asunaprevir for patients with hepatitis C virus genotype 1b aged 75 years and over with or without cirrhosis

AIM

The aim of this study was to evaluate the efficacy and safety of 24-week daclatasvir (NS5A inhibitor) plus asunaprevir (NS3/4 A protease inhibitor) treatment for elderly patients with hepatitis C virus (HCV) genotype 1b infection.

METHODS

This prospective, multicenter study consisted of 321 Japanese HCV genotype 1b patients who were interferon-ineligible/intolerant or non-responders to interferon-based regimens, including 103 (32.1%) aged ≥75 years and 127 (39.6%) with cirrhosis. Sustained virological response (SVR) at 24 weeks after the end of treatment and adverse effects were analyzed according to age.

RESULTS

The overall SVR rate was 90.3%. In terms of by age, 94.5% (69/73), 88.3% (128/145), and 90.3% (93/103) of the patients aged <65, 65-74, and ≥75 years, respectively, achieved SVR. For the entire cohort, pre-existent NS5A resistance-associated variants and prior simeprevir failure were independently associated with treatment failure. According to the analysis of patients without these unfavorable pretreatment factors, 90.8% (89/98) aged ≥75 years achieved SVR, although this was significantly lower than for those aged <65 years (98.5%, 66/67) (P < 0.05). The frequency of adverse effects was comparable for the <75 and ≥75 age groups, the most common being an elevated alanine aminotransferase level (>150 U/L, 8.7%), however, no decompensating events were seen.

CONCLUSIONS

Daclatasvir plus asunaprevir for HCV genotype 1b was well tolerated and effective for patients without pre-existent NS5A resistance-associated variants or simeprevir failure, irrespective of fibrosis status. However, it was less effective for very old patients aged ≥75 years compared to those aged <65.

A Comprehensive Index for Predicting Risk of Anemia from Patients' Diagnoses

This article demonstrates how time-dependent, interacting, and repeating risk factors can be used to create more accurate predictive medicine. In particular, we show how emergence of anemia can be predicted from medical history within electronic health records. We used the Veterans Affairs Informatics and Computing Infrastructure database to examine a retrospective cohort of 9,738,838 veterans over an 11-year period. Using International Clinical Diagnoses Version 9 codes organized into 25 major diagnostic categories, we measured progression of disease by examining changes in risk over time, interactions in risk of combination of diseases, and elevated risk associated with repeated hospitalization for the same diagnostic category. The maximum risk associated with each diagnostic category was used to predict anemia. The accuracy of the model was assessed using a validation cohort. Age and several diagnostic categories significantly contributed to the prediction of anemia. The largest contributors were health status ([Formula: see text] = -1075, t = -92, p < 0.000), diseases of the endocrine ([Formula: see text] = -1046, t = -87, p < 0.000), hepatobiliary ([Formula: see text] = -1043, t = -72, p < 0.000), kidney ([Formula: see text] = -1125, t = -111, p < 0.000), and respiratory systems ([Formula: see text] = -1151, t = -89, p < 0.000). The AUC for the additive model was 0.751 (confidence interval 74.95%-75.26%). The magnitude of AUC suggests that the model may assist clinicians in determining which patients are likely to develop anemia. The procedures used for examining changes in risk factors over time may also be helpful in other predictive medicine projects.

Rapidity and Severity of Hemoglobin Decreasing Associated with Erythrocyte Inosine Triphosphatase Activity and ATP Concentration during Chronic Hepatitis C Treatment

The purpose of this study was to evaluate the association between therapy-induced hemoglobin (Hb) decreasing rapidity and severity with erythrocyte inosine triphosphatase (ITPase) activity and ATP concentration in chronic hepatitis C patients receiving chronic hepatitis C (HCV) treatment. Forty-three Japanese patients were included in the study. Erythrocyte ITPase activity before therapy was determined by HPLC-UV. Erythrocyte ATP concentrations before and during therapy were determined by luciferase assay. Genotyping for ITPA 94C>A (rs1127354) and IVS2+21 A>C (rs7270101) was conducted using TaqMan probes. The median ITPase activity (µmol/h/g hemoglobin) of ITPA 94 CC, CA, and AA genotypes was 136.8 (range, 80.4-289.6), 41.1 (24.3-93.1), and 11.8, respectively. ITPase activity and Hb decreasing showed a significantly inverse relationship at therapeutic weeks 2, 4, and 6 (p<0.01). Erythrocyte ATP concentration was decreased by therapy, and Hb decreasing was significantly and inversely correlated with erythrocyte ATP concentration at week 4 and after week 8 (p<0.001 and 0.05, respectively). ATP concentration for patients with ITPA 94CA was significantly lower than ITPA 94CC at week 4 (p=0.045). We concluded that ITPase activity plays an important function and that ATP concentration changes due to therapy are related to the Hb decreasing mechanism in the early period of therapy with HCV treatment.

Randomized trial of combined triple therapy comprising two types of peginterferon with simeprevir in patients with hepatitis C virus genotype 1b

Simeprevir (SMV) is a potent, macrocyclic hepatitis C virus (HCV) non-structural 3/4 A protease inhibitor. This prospective study compared the efficacy and safety of SMV in combination with peginterferon α2a + ribavirin (P2aR) and with peginterferon α2b + ribavirin (P2bR) in Japanese patients with HCV genotype 1b infection.

METHODS

Hepatitis C virus genotype 1b patients were randomly assigned to receive SMV (100 mg QD) with P2aR for 12 weeks, then P2aR alone for 12 or 36 weeks; or SMV (100 mg QD) with P2bR for 12 weeks, then P2bR alone for 12 or 36 weeks. The primary endpoint was a sustained virologic response 24 weeks after completing treatment (SVR24).

RESULTS

In total, 151 patients were randomly assigned to the P2aR (n = 76) or P2bR group (n = 75). Six patients dropped out. Sustained virologic response 24 weeks after completing treatment was achieved in 55 (75.3%) of 73 P2aR patients and 55 (76.4%) of 72 P2bR patients. There was no difference in the rate of SVR24 between the two groups (P = 0.88). No differences in the proportion of patients who became HCV RNA-negative were detected between the P2aR and P2bR groups. The two groups had comparable numbers of adverse events, which led to the discontinuation of treatment in 9.6% and 8.3% of participants in the P2aR and P2bR groups, respectively.

CONCLUSION

Peginterferon α2a or α2b in combination with SMV + ribavirin therapy showed identical antiviral effects in patients with chronic hepatitis C. Also, the incidence of adverse events was identical for both regimens.

Effectiveness and safety of sofosbuvir plus ribavirin for HCV genotype 2 patients 65 and over with or without cirrhosis

Older patients with chronic hepatitis C virus (HCV) infection have historically been designated difficult-to-treat. We evaluated the efficacy and safety of sofosbuvir (nucleotide NS5B polymerase inhibitor) plus ribavirin for patients with HCV genotype 2 infection in a real-world clinical setting, with the focus on elderly patients aged ≥ 65. This large, multicenter study consisted of 446 Japanese HCV genotype 2 patients (303 treatment-naïve and 143 treatment-experienced), including 190 (42.6%) aged ≥ 65 and 90 (20.2%) with compensated cirrhosis. Efficacy was assessed by the sustained virological response 12 weeks post-treatment (SVR12). The overall SVR12 rate was 95.7% (427/446), and the SVR12 rate of patients aged ≥ 65 was 95.3% (181/190). For treatment-naïve patients, almost all with compensated cirrhosis (95.6%, 43/45) achieved SVR12, irrespective of age. For treatment-experienced patients, cirrhosis undermined the treatment outcome, both for the aged ≥65 (SVR12: 80.0%, 20/25) and <65 (85.0%, 17/20) patient groups when compared to non-cirrhosis patients (≥65: 95.7%, 45/47 and < 65: 96.2%, 50/52). The most common adverse effect was anemia (hemoglobin <10 g/dL), especially for patients aged ≥ 65 with the inosine triphosphate pyrophosphatase CC genotype at rs1127354 (26.2%, 33/126). Notably, ribavirin reduction was not related to treatment failure. Only three (0.7%) patients, all aged ≥ 65, discontinued treatment, but all achieved SVR12. Sofosbuvir plus ribavirin for HCV genotype 2 was effective for patients aged ≥65, especially those who were treatment-naïve or treatment-experienced/non-cirrhosis.

Anemia and iron deficiency in gastrointestinal and liver conditions

Iron deficiency anemia (IDA) is associated with a number of pathological gastrointestinal conditions other than inflammatory bowel disease, and also with liver disorders. Different factors such as chronic bleeding, malabsorption and inflammation may contribute to IDA. Although patients with symptoms of anemia are frequently referred to gastroenterologists, the approach to diagnosis and selection of treatment as well as follow-up measures is not standardized and suboptimal. Iron deficiency, even without anemia, can substantially impact physical and cognitive function and reduce quality of life. Therefore, regular iron status assessment and awareness of the clinical consequences of impaired iron status are critical. While the range of options for treatment of IDA is increasing due to the availability of effective and well-tolerated parenteral iron preparations, a comprehensive overview of IDA and its therapy in patients with gastrointestinal conditions is currently lacking. Furthermore, definitions and assessment of iron status lack harmonization and there is a paucity of expert guidelines on this topic. This review summarizes current thinking concerning IDA as a common co-morbidity in specific gastrointestinal and liver disorders, and thus encourages a more unified treatment approach to anemia and iron deficiency, while offering gastroenterologists guidance on treatment options for IDA in everyday clinical practice.

ITPA deficiency and ribavirin level are still predictive of anaemia in HCV-HIV-coinfected patients receiving ribavirin combined with a first-generation DAA (ANRS HC27 study)

BACKGROUND

We aimed to determine the impact of inosine triphosphatase (ITPA) deficiency on ribavirin (RBV)-induced anaemia in HIV-HCV-coinfected patients receiving a triple therapy including the haematotoxic direct-acting antiviral agent boceprevir (BOC).

METHODS

Patients of the ANRS HC27 BocepreVIH study were genotyped for two ITPA single nucleotide polymorphisms involved in ITPA deficiency. RBV trough concentration (Ctrough) was determined at week (W)4 and W8. Impact of ITPA deficiency on anaemia, RBV Ctrough, response and haematotoxicity (grade 3/4 anaemia, erythropoietin [EPO] use, RBV dose reduction or transfusion between day [D]0 and W8) was evaluated. Impact of RBV Ctrough on anaemia was also studied.

RESULTS

Among the 63 genotyped patients, 33% had a predicted ITPA deficiency. ITPA deficiency was associated with a lower haemoglobin (Hb) decline both at W4 (-1.0 g/dl versus -2.1 g/dl; P=0.02) and W8 (-2.7 g/dl versus -4.1 g/dl; P=0.05). None of the patients with ITPA deficiency received EPO between D0-W8 versus 26% of patients without ITPA deficiency (P=0.01). RBV Ctrough was associated with Hb decrease both at W4 and W8 and an RBV Ctrough cutoff value of 2 µg/ml was significantly associated with a W4 Hb decline >2 g/dl. Haematotoxicity was significantly associated with a lower W4 Hb level (P=0.017), absence of ITPA deficiency (P=0.018) and higher RBV Ctrough (P=0.012). ITPA deficiency, W4 RBV Ctrough and gender were independent predictors of anaemia at W4. ITPA deficiency was not associated with virological response.

CONCLUSIONS

ITPA deficiency and RBV Ctrough are still predictive of RBV-induced anaemia in HIV-HCV-coinfected patients treated with RBV combined with a first-generation direct antiviral agent.

Pharmacogenetics of ribavirin-induced anemia in hepatitis C

Pharmacogenetics assesses inherited genetic differences in drug metabolic pathways and its role in medicine is growing. Ribavirin (RBV) and peginterferon were the standard of care therapy in hepatitis C virus infection during 15 years, with the addition of first-generation protease inhibitors at the beginning of 2010s. New direct-acting agents are the new standard of care, but RBV remains important in some scenarios. The main adverse effect of RBV is anemia, which requires dose reduction and even stopping treatment in some patients. Pharmacogenetics has identified ITPA and SLC28/29 genes to be closely related to RBV-induced anemia. The routine evaluation of these genes could help to identify those patients at risk of developing anemia during the hepatitis C virus treatment.

Pharmacogenetics of ribavirin-induced anemia in HCV patients

Dual therapy (pegylated interferon plus ribavirin) was considered the standard of care for hepatitis C virus (HCV) treatment until 2011, when the first-wave direct-acting antivirals were added to this regimen for HCV genotype-1 patients to increase the sustained virological response rate. The second-wave direct-acting antivirals entered the clinical use also in some ribavirin (RBV)- and/or interferon-free combinations. Nevertheless, since some of the new therapeutic regimens also include RBV and its use results still associated with hemolytic anemia, this requires countermeasures to be prevented. These include the identification of several host predictive factors involved in RBV absorption, distribution, metabolism, elimination and many others that might influence this toxic effect. For this reason, we provided an overview of the potential role of pharmacogenomics in predisposing RBV-treated HCV patients to anemia.

Protease inhibitors-based therapy induces acquired spherocytic-like anaemia and ineffective erythropoiesis in chronic hepatitis C virus patients

BACKGROUND & AIMS

The addition of protease inhibitors, boceprevir (BOC) or telaprevir (TRV), to peg-interferon and ribavirin (PR) increases the incidence of anaemia in patients with chronic hepatitis C virus (HCV) infection. Although genetic variants in inosine triphosphatase (ITPA) gene have been linked to the haemolytic anaemia induced by PR, the mechanism sustaining severe anaemia during triple therapy is still unknown. This study aims to elucidate the molecular mechanisms underlying anaemia in chronic HCV patients with combined therapy.

METHODS

We studied 59 patients with chronic HCV genotype-1: 29 treated with TRV/PR and 30 with BOC/PR. We evaluated biochemical and haematological parameters, red cell index at baseline, 4, 12, 16 and 24 weeks of treatment; in a subgroup, we performed functional studies: osmotic fragility, red cell membrane protein separation, mass spectrometry analysis, quantification of erythroid microparticles release. IL28B and ITPA polymorphisms were also evaluated.

RESULTS

We found early acute normochromic normocytic haemolytic anaemia (4-8 weeks) followed by a late macrocytic hypo-regenerative anaemia with inappropriate low reticulocyte count (12-24 weeks). Studies on red cells revealed: (i) presence of spherocytes; (ii) increased osmotic fragility; (iii) abnormalities in red cell membrane protein composition; (iv) reduced membrane-cytoskeleton stability; (v) increased release of erythroid microparticles. ITPA polymorphisms impacted only the early phase of anaemia.

CONCLUSIONS

The bimodal pattern of anaemia in chronic HCV patients on triple therapy might be because of acquired spherocytic-like anaemia in the early phase, followed by hyporegenerative anaemia, most likely related to the combined effects of PR and TRV or BOC on erythropoiesis.

ITPA Genotypes Predict Anemia but Do Not Affect Virological Response with Interferon-Free Faldaprevir, Deleobuvir, and Ribavirin for HCV Infection

Background & Aim

Whether inosine triphosphatase (ITPA) gene polymorphisms predict anemia during interferon-free therapy in chronic hepatitis C virus (HCV)-infected patients is unknown. We examined the relationship between two ITPA polymorphisms, anemia, and sustained virological response 12 weeks post-treatment (SVR12) in patients receiving the NS3/4A protease inhibitor faldaprevir, the non-nucleoside polymerase inhibitor deleobuvir, and ribavirin.

Methods

HCV genotype 1-infected, treatment-naïve patients (N = 362) were randomized and treated in one of five treatment arms with faldaprevir and deleobuvir with or without ribavirin. Two ITPA polymorphisms (rs1127354 and rs6051702) were genotyped and defined as ITPA-deficient (rs1127354 AA or AC; rs6051702 CC or CA) or ITPA-non-deficient (rs1127354 CC; rs6051702 AA) according to their association with ITPA deficiency. Baseline and on-treatment variables associated with anemia and SVR12 were identified using logistic regression.

Results

In the pooled ribavirin-containing arms, 10.1% (32/316) of patients experienced on-treatment hemoglobin <10 g/dL, and 32.6% (103/316) experienced on-treatment hemoglobin <10 g/dL or a change from baseline ≥3.5 g/dL. Of the latter group, 99% (102/103) had the ITPA-non-deficient rs1127354 genotype. Other variables associated with on-treatment hemoglobin <10 g/dL or a decrease ≥3.5 g/dL were age, baseline hemoglobin, rs6051702 genotype, and plasma ribavirin concentration. In a multivariate analysis, high plasma ribavirin concentration, low baseline hemoglobin, HCV genotype 1b, and IL28B genotype CC were associated with higher SVR12.

Conclusions

The ITPA rs1127354 CC and rs6051702 AA genotypes may predict ribavirin-induced anemia during treatment with interferon-free, ribavirin-containing regimens. With this interferon-free regimen, SVR was associated with ribavirin levels, but not with anemia or ITPA genotypes.

Trial Registration

ClinicalTrials.gov: NCT01132313

Comparative effectiveness and safety study of triple therapy with simeprevir or telaprevir for non-cirrhotic patients with chronic hepatitis C virus genotype 1b infection

BACKGROUND AND AIM

The addition of hepatitis C virus (HCV) NS3/4A protease inhibitors to pegylated-interferon alpha (PEG-IFNα) and ribavirin (triple therapy) has greatly improved treatment outcome. The aim of this study was to compare the effectiveness and safety of simeprevir-based or telaprevir-based triple therapy for non-cirrhotic patients in real-world clinical practice.

METHODS

This multicenter study consisted of 835 consecutive Japanese HCV genotype 1b patients treated in a clinical setting, 716 of whom were enrolled (simeprevir = 256 and telaprevir = 460). Logistic regression was carried out after propensity score matching to assess the sustained virological response at week 12 after the end of treatment (SVR12).

RESULTS

In the propensity-matched cohort (253 matched pairs), the SVR12 rates of the patients who underwent simeprevir-based or telaprevir-based triple therapy were 85.0% and 84.2%, respectively, by intention-to-treat analysis. Prior treatment response to PEG-IFNα/ribavirin and IL28B genotype was independently associated with SVR12 in both groups. No significant differences in the SVR12 rates stratified by prior treatment response to PEG-IFNα/ribavirin were found between the simeprevir (treatment-naïve 89.1%, prior relapse 94.3%, prior partial response 65.0%, and prior null response 33.3%) and telaprevir (treatment-naïve 87.8%, prior relapse 90.1%, prior partial response 68.4%, and prior null response 50.0%) groups. The incidence of adverse effects, such as anemia, severe rash, and the elevation of serum creatinine, was markedly higher in the telaprevir group.

CONCLUSIONS

Considering the effectiveness and safety, simeprevir-based triple therapy will continue to be a useful treatment option in Japan for treatment-naïve or prior relapse patients with a favorable IL28B genotype.

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.

Importance of virological response in the early stage of telaprevir-based triple therapy for hepatitis C

AIM: To investigate the efficacy of virological response (VR) to telaprevir (TVR)-based triple therapy in predicting treatment outcome of hepatitis C.

METHODS: This prospective, multicenter study consisted of 253 Japanese patients infected with hepatitis C virus (HCV) genotype 1b. All received 12 wk of TVR in combination with 24 wk of pegylated-interferon-α (IFN-α) and ribavirin. Serum HCV RNA was tested at weeks 1, 2, 3, 4, 6, 8, 12, 16, 20, and 24. VR was defined as undetectable serum HCV RNA. Sustained virological response (SVR) was VR at 24 wk after the end of treatment and was regarded as a successful outcome.

RESULTS: Of 253 patients, 207 (81.8%) achieved SVR. The positive predictive value of VR for SVR was 100% at week 2, after which it gradually decreased, and was over 85% to week 12. The negative predictive value (NPV) gradually increased, reaching 100% at week 12. The upslope of the NPV showed a large increase from week 4 (40.6%) to week 6 (82.4%). There was a moderate concordance between the SVR and VR at week 6 (kappa coefficient = 0.44), although other VRs had poor concordance to SVR. Multiple logistic regression analysis extracted VR at week 6 (P < 0.0001, OR = 63.8) as an independent factor contributing to SVR. In addition, the interleukin-28B single nucleotide polymorphism and response to previous pegylated-IFN-α and ribavirin therapy were identified as independent factors for SVR.

CONCLUSION: VR at week 6, but not at week 4, is an efficient predictor of both SVR and non-SVR to TVR-based triple therapy.

ITPA Polymorphisms Are Associated with Hematological Side Effects during Antiviral Therapy for Chronic HCV Infection

Background/Objective

Genetic polymorphisms in the inosine triphosphatase (ITPA) gene have been associated with the protection from early ribavirin(RBV)-induced hemolytic anemia among patients with chronic hepatitis C virus (HCV) infection. The aim of the present study was to investigate the association between the functional ITPA variants and hematological side effects during antiviral therapy with pegylated interferon (PegIFN) and RBV.

Patients and Methods

This cohort study included all consecutive Caucasian patients treated for chronic HCV infection with PegIFN and RBV between 2000 and 2009 for whom a serum sample was available for genetic testing. The predicted inosine triphosphate pyrophosphatase (ITPase) activity was based on the genotypes of the SNPs rs1127354 and rs7270101. Decline in hemoglobin (Hb) during antiviral therapy, as well as dose reductions, blood transfusions and use of erythropoietin were assessed.

Results

In total, 213 patients were included. The predicted ITPase activity was normal among 152 (71%) patients; 61 (29%) patients had ITPase deficiency. By multivariable linear regression, RBV dose in mg per kilogram (Beta 0.09, 95%CI 0.04–0.13, p<0.001) and normal ITPase activity (Beta 0.89, 95%CI 0.64–1.14, p<0.001) were associated with more Hb decline at week 4 of treatment. Patients with normal ITPase activity underwent more dose adjustments of RBV than patients with ITPase deficiency (19(13%) vs 1(2%),p = 0.014) and received erythropoietin more frequently (12 (8%) vs 0 (0%),p = 0.024).

Conclusion

Genetic variants in the ITPA gene protected against RBV treatment-induced anemia among Caucasian patients with chronic HCV infection. Patients with normal ITPase activity underwent more dose reductions of RBV and received erythropoietin more frequently.

Relationship between ITPA polymorphisms and hemolytic anemia in HCV-infected patients after ribavirin-based therapy: a meta-analysis

BACKGROUND

There is growing evidence that variations in the gene encoding inosine triphosphate pyrophosphohydrolase (ITPase), known as inosine triphosphatase (ITPA), are related to hemolytic anemia, which is frequently observed among hepatitis C virus (HCV)-infected patients receiving ribavirin (RBV)-based therapy. We performed a meta-analysis of all eligible studies assessing ITPA gene polymorphisms related to RBV-induced hemolytic anemia in HCV-infected patients published in PubMed, Embase and the Cochrane library prior to the end of 2014.

METHODS

Three outcomes were evaluated: (1) hemoglobin decline, (2) severe anemia, and (3) RBV dose reduction or treatment discontinuation. Pooled odds ratio (OR) and 95 % confidence interval (95 % CI) were estimated by either fixed or random effects models.

RESULTS

Twenty-nine studies were selected from the literature search: 20 references involving 6533 individuals for hemoglobin decline, 13 references on 3764 patients for severe anemia, and 16 references on 3918 patients for RBV dose reduction or discontinuation. Significant associations with hemoglobin decline were found for rs1127354 CC [OR = 12.84 (95 % CI 7.44; 22.17)], rs7270101 AA [OR = 3.41 (95 % CI 2.08; 5.59)] and rs6051702 AA [OR = 4.43 (95 % CI 2.80; 7.00)] genotypes. Moreover, significant associations with hemoglobin decline were also found for absent [OR = 6.01 (95 % CI 4.84; 7.46)] and mild [OR = 4.68 (95 % CI 2.83; 7.74)] ITPase deficiency haplotypes. The ITPA rs1127354 CC genotype and absent ITPase deficiency haplotype were also associated with severe anemia {[OR = 7.77 (95 % CI 5.03; 12.00)] and [OR = 4.79 (95 % CI 1.69; 13.56)], respectively}. Additionally, the rs1127354 CC genotype showed significant association with RBV dose reduction or stopping treatment (OR = 2.24; 95 % CI 1.79; 2.81).

CONCLUSIONS

ITPA polymorphisms increase the likelihood of developing hemolytic anemia for HCV-infected patients on RBV-based therapy, particularly rs1127354 CC and rs7270101 AA genotypes, suggesting the utility of screening for ITPA polymorphisms to avoid hematological toxicity and increase adherence to RBV-based therapy.

Telaprevir-based triple therapy following partial splenic arterial embolization for chronic hepatitis C with thrombocytopenia can reduce carcinogenesis and improve hepatic function reserve

Thrombocytopenia in patients with chronic hepatitis C negatively impacts interferon (IFN)-based treatment. The aim of this study was to evaluate the efficacy and safety of telaprevir (TVR)-based triple therapy including IFN for patients who have undergone partial splenic arterial embolization (PSE). Ten patients with thrombocytopenia who were infected with hepatitis C virus (HCV) genotype 1b received 12 weeks of TVR in combination with 24 weeks of pegylated interferon (PEG-IFN)α2b and ribavirin following PSE. A sustained virological response (SVR) was seen in 9 of the 10 patients who could be assessed. Early relapse was seen in 1 patient who had the IL-28B minor allele and a null response to pretreatment. The α-fetoprotein levels of the patients decreased from 17.94±7.30 ng/ml prior to PSE to 4.33±2.41 ng/ml at 6 months after triple therapy (P=0.08). Furthermore, serum albumin levels improved significantly from 3.68±0.49 g/dl pre-PSE to 4.13±0.34 g/dl at 12 months after triple therapy (P=0.043). PSE contributed to the treatment success of triple therapy, particularly for patients who were either treatment-naïve, had a history of relapse or the IL28B major allele. This strategy can reduce carcinogenesis and improve hepatic function reserve.

Role of genetic polymorphisms in hepatitis C virus chronic infection

AIM: To analyze the host genetics factors influencing the clinical course and the response to antiviral treatment in patients with chronic hepatitis C (CHC).

METHODS: We conducted an electronic search on the PubMed and MEDLINE (2000-2014) databases and Cochrane library (2000-2014). A total of 73 articles were retrieved and their data were extensively evaluated and discussed by the authors and then analyzed in this review article.

RESULTS: Several studies associated polymorphisms in the interleukin 28B gene on chromosome 19 (19q13.13) with a spontaneous viral clearance in acute hepatitis C and with the response to pegylated interferon (Peg-IFN)-based treatment in chronic hepatitis C patients. Other investigations demonstrated that inosine triphosphate pyrophosphatase genetic variants protect hepatitis C virus-genotype-1 CHC patients from ribavirin-induced anemia, and other studies that a polymorphism in the patatin-like phospholipase domain-containing protein 3 was associated with hepatic steatosis in CHC patients. Although not conclusive, some investigations suggested that the vitamin D-associated polymorphisms play an important role in the achievement of sustained virologic response in CHC patients treated with Peg-IFN-based antiviral therapy. Several other polymorphisms have been investigated to ascertain their possible impact on the natural history and on the response to treatment in patients with CHC, but the data are preliminary and warrant confirmation.

CONCLUSION: Several genetic polymorphisms seem to influence the clinical course and the response to antiviral treatment in patients with CHC, suggesting individualized follow up and treatment strategies.

Comparative safety study on severe anemia by simeprevir versus telaprevir-based triple therapy for chronic hepatitis C

BACKGROUND AND AIM

The addition of hepatitis C virus (HCV) NS3/4A protease inhibitors to the pegylated interferon (PEG-IFN) α and ribavirin combination regimen (triple therapy) has dramatically improved treatment outcome. Unfortunately, anemia remains a common adverse effect. This study was done to compare the development of severe anemia during simeprevir- or telaprevir-based triple therapy.

METHODS

This retrospective multicenter study consisted of 837 consecutive Japanese HCV genotype 1 patients treated in a real-world clinical setting, 811 of whom were enrolled (simeprevir 281, telaprevir 530). The inosine triphosphate pyrophosphatase (ITPA) genotype at rs1127354 was determined for all studied patients. Logistic regression was done after propensity score matching to assess the risk of development of severe anemia.

RESULTS

Propensity score matching of the entire study population yielded 266 matched pairs. Severe anemia (nadir hemoglobin < 9.0 g/dL) was developed during the treatment period by 81 (30.5%) and 144 (54.1%) patients treated with simeprevir and telaprevir, respectively. Treatment with simeprevir was independently associated with a lower risk of severe anemia (odds ratio 0.25, 95% confidence interval 0.16-0.38, P < 0.0001). Moreover, ITPA genotype, age, hemoglobin level, and estimated glomerular filtration rate at baseline were also independent factors associated with the development of severe anemia.

CONCLUSIONS

Patients treated with simeprevir-based triple therapy have a lower risk of the development of severe anemia than those treated with telaprevir. Moreover, ITPA genotype and age may be useful for individualizing treatment to reduce the risk of anemia-related adverse effects.

Progress in understanding the genomic basis for adverse drug reactions: a comprehensive review and focus on the role of ethnicity

A major goal of the field of pharmacogenomics is to identify the genomic causes of serious adverse drug reactions (ADRs). Increasingly, genome-wide association studies (GWAS) have been used to achieve this goal. In this article, we review recent progress in the identification of genetic variants associated with ADRs using GWAS and discuss emerging themes from these studies. We also compare aspects of GWAS for ADRs to GWAS for common diseases. In the second part of the article, we review progress in performing pharmacogenomic research in multi-ethnic populations and discuss the challenges and opportunities of investigating genetic causes of ADRs in ethnically diverse patient populations.

Role of ITPA and SLC28A2 genes in the prediction of anaemia associated with protease inhibitor plus ribavirin and peginterferon in hepatitis C treatment

BACKGROUND

Anaemia is a common side-effect of ribavirin (RBV) use that overwhelms management of hepatitis C when protease inhibitors are added.

AIM

To assess the pharmacogenomic impact of candidate genes SLC28A2, SLC28A3 and ITPA on anaemia in patients receiving triple therapy.

METHODS

Patients (n=161) with chronic hepatitis C genotype 1 treated with telaprevir (n=95) or boceprevir (n=66) were included. Using RT-PCR we genotyped ITPA (rs1127354, rs7270101) and SLC28A3 (rs56350726, rs10868138) and SLC28A2 (rs11854484). Clinically significant anaemia (CSA) was diagnosed when at least one of the following criteria was observed: (a) haemoglobin <8.5g/dL during treatment; (b) blood transfusion required; (c) erythropoietin administered.

RESULTS

CSA occurred in 44% (69/157) of patients and was associated with SLC28A2 rs11854484 [CC/CT genotypes: 33% (26/78) vs. TT genotype: 56% (36/64); p=0.006]. Further, the needed for blood transfusion was related to genotype [CC: 0% (0/18) vs. CT: 13% (8/61) vs. TT: 27% (17/64); p=0.016]. Similarly, ITPA rs1127354 genotypes [AA/AC: 19% (3/16) vs. CC: 45% (61/135; p=0.060] were linked to CSA. In multivariate analysis, SLC28A2 rs11854484 TT genotype (OR:2.33;95%CI:1.10-4.95; p=0.027), female sex (OR:2.54;95% CI:1.13-5.71;p=0.024) and Hb drop at week 4) OR: 1.36; 95CI%: 1.11-1.67; p=0.003) were independently associated with CSA. Similarly, ITPA rs1127354 genotypes [AA/AC: 16% (3/19) vs. CC: 63% (85/134); p=0.0001] and ITPA rs6051702 genotypes [CC/CA: 46% (26/57) vs. CC: 65% (60/93); p=0.023] were related to Hb drop of >3g/dL at week 4.

CONCLUSIONS

In patients receiving first generation protease inhibitors, genotype SLC28A2 rs11854484 predicts CSA, and helps to identify a subgroup of patients with better tolerance of triple therapy.

Ribavirin dose reduction during telaprevir/ribavirin/peg-interferon therapy overcomes the effect of the ITPA gene polymorphism

Treatment success of chronic hepatitis C virus genotype 1 infection has improved with the advent of telaprevir plus peg-interferon/ribavirin triple combination therapy. However, the effect of inosine triphosphatase (ITPA) polymorphism on dose reduction during triple therapy, especially during the postmarketing phase, has not been sufficiently evaluated. We analysed 273 patients with genotype 1 infection who were treated with triple therapy and assessed the effect of the ITPA polymorphism on dose reduction. ITPA and IFNL4 SNP genotypes were determined by the Invader assay. A stepwise multivariate regression analysis was performed to identify factors associated with outcome of the therapy. The overall sustained viral response (SVR) rate 12 weeks after the end of therapy was 80.2% (219/273). Decline of haemoglobin was significantly faster, and ribavirin was more extensively reduced in patients with ITPA SNP rs1127354 genotype CC than CA/AA. Extensive reduction of ribavirin resulted in mild reduction of telaprevir and peg-interferon, but no significant increase in viral breakthrough. Although the amount of telaprevir given was slightly higher in CA/AA patients, the total dose of peg-interferon and the SVR rate did not differ between the two groups. Multivariate analysis showed that IFNL4 but not ITPA SNP genotype, platelet count and peg-interferon adherence were significantly associated with outcome of therapy. Postmarketing-phase triple therapy resulted in a high SVR rate in spite of extensive ribavirin dose reduction in a diverse patient population, indicating the importance of treatment continuation and appropriate management of adverse events.

SLC29A1 polymorphism and prediction of anaemia severity in patients with chronic hepatitis C receiving triple therapy with telaprevir

OBJECTIVES

The equilibrative nucleoside transporter 1 (ENT1) is the main protein involved in ribavirin cellular uptake. Polymorphisms at the SLC29A1 gene, encoding ENT1, may influence ribavirin-associated anaemia, which is observed at a higher incidence with telaprevir in combination with pegylated-IFNα and ribavirin than with pegylated-IFNα and ribavirin alone. In this study, we investigated the role of the rs760370 SLC29A1 variant in ribavirin-induced anaemia in chronic hepatitis C patients treated with telaprevir-based triple therapy.

METHODS

Forty patients infected with hepatitis C virus (HCV) genotype 1 and starting anti-HCV therapy with telaprevir in combination with pegylated-IFN/ribavirin were prospectively evaluated for SNPs at the SLC29A1 gene and inosine triphosphatase (ITPA) genes using a real-time PCR system.

RESULTS

40% of patients developed severe anaemia with a haemoglobin (Hb) decline ≥ 5 g/dL from the pretreatment value. The SLC29A1 rs760370 GG genotype was associated with the severity of Hb decrease as expressed by the median (IQR) Hb nadir change from baseline [-5.4 (-5.6; -5.0) g/dL in GG versus -4.2 (-5.1; -3.4) in AA/AG genotype; P=0.05] and by the Hb decrease ≥ 5 g/dL by week 12 (77.8% of GG carriers versus 24% of AA/AG; P<0.01). In multivariate analysis, older age (P=0.03), lower baseline Hb concentration (P=0.02) and SLC29A1 rs760370 GG (P=0.02) were associated with the development of severe anaemia during treatment, whereas no association was found with ITPA SNPs in our population receiving telaprevir-based therapy.

CONCLUSIONS

In patients with chronic hepatitis C receiving telaprevir-based therapy, SNP rs760370A>G at the SLC29A1 gene influences the severity of ribavirin-induced anaemia, possibly mirroring the erythrocyte uptake of ribavirin.

Effects on anemia of drug adjustment in patients with chronic hepatitis C during telaprevir-combined therapy

AIM

Anemia is the most common adverse event in patients with chronic hepatitis C virus (HCV) treated with telaprevir (TVR) combined triple therapy. We examined the effects of drug dose adjustment on anemia and a sustained viral response (SVR) during combination therapy.

MATERIAL AND METHODS

This study enrolled 62 patients treated with TVR (2,250 mg) for 12 weeks plus pegylated interferon-alpha-2b and ribavirin for 24 weeks. The patients were assigned randomly to the TVR-standard or -reduced groups before treatment. At the occurrence of anemia (hemoglobin < 12 g/dL), the TVR-reduced group received 1500 mg TVR plus the standard dose of ribavirin, whereas the TVR-standard group received the standard TVR dose (2,250 mg) and a reduced dose of ribavirin (200 mg lower than prescribed originally). The safety and SVR at 24 weeks were compared between the TVR-standard (n = 28) and TVR-reduced (n = 25) groups.

RESULTS

No differences in the proportion of patients who became HCV RNA-negative were detected between the TVR-standard and -reduced groups (72 and 72% at week 4, 79 and 84% at the end of treatment, and 76 and 80% at SVR24, respectively). Two groups had comparable numbers of adverse events, which led to the discontinuation of TVR in 14 patients of TVR-standard group and in 14 of TVR-reduced group. A lower incidence of renal impairment was observed in the TVR-reduced group (6%) than the TVR-standard group (11%, not statistically significant).

CONCLUSIONS

TVR dose adjustment could prevent anemia progression without weakening the anti-viral effect during triple therapy in HCV-patients.

Bacterial infection as an adverse effect of telaprevir-based triple therapy for chronic hepatitis C infection

OBJECTIVE

There is little information regarding the incidence of bacterial infections as an adverse effect of telaprevir (TVR)-based triple therapy. This study was performed in order to evaluate the baseline and on-treatment predictors of bacterial infections in patients treated with TVR-based triple therapy.

METHODS

This multicenter study evaluated 430 patients with chronic hepatitis C who received 12 weeks of TVR in combination with 24 weeks of pegylated interferon α2b plus ribavirin. The occurrence of a bacterial infection during anti-viral treatment was defined as the onset of local or systemic inflammation as a result of pathogenic bacteria.

RESULTS

Bacterial infections occurred in 21 of the 430 (4.9%) patients during TVR-based triple therapy. Among these subjects, 71.4% (15 of 21) experienced bacterial infections during the initial eight weeks of treatment. Urinary tract infections were the most frequent infection, observed in 2.8% of cases (12 of 430). The rate of urinary tract infection among women (11 of 215, 5.1%) was significantly higher than that observed among men (1 of 215, 0.5%) (p<0.0001). According to a multivariable logistic regression analysis, the only significant independent predictor was the pretreatment serum albumin level (p=0.0008). Of the 21 patients who experienced bacterial infections, only one (4.8%) had to discontinue the treatment; however, the others were able to continue anti-viral treatment in combination with antibiotic treatment.

CONCLUSION

Clinicians should be concerned regarding the incidence of bacterial infections among patients treated with TVR-based triple therapy, especially those with a low serum albumin level.

Clinical utility of pharmacogenomics in the management of hepatitis C

Hepatitis C virus (HCV) was identified for the first time more than 20 years ago. Since then, several studies have highlighted the complicated aspects of this viral infection in relation to its worldwide prevalence, its clinical presentation, and its therapeutic response. Recently, two landmark scientific breakthroughs have moved us closer to the successful eradication of chronic HCV infection. First, response rates in treatment-naïve patients and in prior non-responders to pegylated-interferon-α and ribavirin therapy are increasing as a direct consequence of the development of direct-acting antiviral drugs. Secondly, the discovery of single-nucleotide polymorphisms near the interleukin 28B gene significantly related to spontaneous and treatment-induced HCV clearance represents a milestone in the HCV therapeutic landscape. The implementation of this pharmacogenomics finding as a routine test for HCV-infected patients has enhanced our understanding of viral pathogenesis, has encouraged the design of ground-breaking antiviral treatment regimens, and has become useful for pretreatment decision making. Nowadays, interleukin 28B genotyping is considered to be a key diagnostic tool for the management of HCV-infected patients and will maintain its significance for new combination treatment schemes using direct-acting antiviral agents and even in interferon-free regimens. Such pharmacogenomics insights represent a challenge to clinicians, researchers, and health administrators to transform this information into knowledge with the aim of elaborating safer and more effective therapeutic strategies specifically designed for each patient. In conclusion, the individualization of treatment regimens for patients with hepatitis C, that may lead to a universal cure in future years, is becoming a reality due to recent developments in biomarker and genomic medicine. In light of these advances, we review the scientific evidence and clinical implications of recent findings related to host genetic factors in the management of HCV infection.

Erythropoietin rs1617640 G allele associates with an attenuated rise of serum erythropoietin and a marked decline of hemoglobin in hepatitis C patients undergoing antiviral therapy

BACKGROUND

A decline in hemoglobin (Hb) concentration during antiviral therapy in chronic hepatitis C (CHC) is a serious side effect. It may compel to dose reduction or even termination of antiviral treatment. The activation of erythropoietin (EPO) synthesis as a physiological response to anemia and its relation to a genetic variation within the EPO gene has not been evaluated yet.

METHODS

Data of 348 CHC patients were reviewed retrospectively. Samples were genotyped for EPO rs1617640 and inosine triphosphatase (ITPA) rs1127354. Serum EPO concentrations were determined before and during therapy. Primary endpoints were set as Hb decline >3 g/dl at weeks 4 and 12.

RESULTS

EPO rs1617640 G homozygotes showed a significantly lower rise of serum EPO level over time than T allele carriers (p < 0.001). The cumulative frequency of a significant Hb reduction added up to 40%. Multivariate analysis revealed that besides age, ribavirin starting dose and baseline Hb also EPO rs1617640 G homozygosity associates with Hb reduction at week 4 (p = 0.025) and 12 (p = 0.029), while ITPA C homozygotes are at risk for Hb decline particularly early during treatment. Furthermore, EPO rs1617640 G homozygotes were more frequently in need for blood transfusion, epoetin-α supplementation, or ribavirin dose reduction (p < 0.001).

CONCLUSIONS

Our data suggest that EPO rs1617640 genotype, the rise of serum EPO concentration as well as ITPA rs1127354 genotype are promising parameters to evaluate the Hb decline during antiviral therapy. A rational adjustment of therapy with epoetin-α supplementation might prevent serious adverse events or the need to terminate treatment.

Efficacy and safety of splenectomy in telaprevir-based triple therapy for chronic hepatitis C patients with thrombocytopenia and advanced fibrosis

BACKGROUND AND AIM

Thrombocytopenia (TCP) of chronic hepatitis C patients with cirrhosis has a negative impact on the management of interferon-based treatment. The aim of this study is to evaluate the efficacy and safety of telaprevir-based triple therapy for patients who have undergone splenectomy (Spx).

METHODS

This prospective, multicenter study consisted of 80 patients, including 32 Spx and 48 non-Spx/TCP (platelet count: 60-99 × 10(9) /L) patients with advanced fibrosis infected with hepatitis C virus genotype 1b. All received 12 weeks of telaprevir in combination with 24 weeks of pegylated interferon (PEG-IFN) α2b and ribavirin.

RESULTS

The sustained virological response (SVR) rate of the Spx group (75.0%) was significantly higher than that of the non-Spx/TCP group (52.1%) (P < 0.05). Under favorable conditions such as treatment-naïve/prior relapse and interleukin-28B (IL28B) TT allele (rs8099917), the SVR rates of the Spx group were significantly higher than those of the non-Spx/moderate TCP (60-79 × 10(9) /L) groups (91.3% vs 50.0% and 93.8% vs 37.5%, respectively; both P < 0.05). Adequate PEG-IFNα2b adherence was associated with SVR. However, the percentage of patients who achieved 80% adherence to PEG-IFNα2b in the non-Spx/moderate TCP (42.9%) group was significantly lower than that of the Spx (79.3%) and non-Spx/mild TCP (80-99 × 10(9) /L) (80.0%) groups. Treatment discontinuation due to adverse effects and the development of bacterial infection did not differ between the Spx and non-Spx/TCP groups.

CONCLUSION

The increase of platelet count after Spx contributed to treatment success, especially for moderate to severe TCP patients who are treatment-naïve/prior relapse or IL28B TT allele.

A case of successful treatment with telaprevir-based triple therapy for hepatitis C infection after treatment failure with vaniprevir-based triple therapy

Recently direct-acting antiviral agents, such as hepatitis C virus (HCV) non-structural 3/4A (NS3/4A) protease inhibitors (PI), have been introduced, and triple therapy regimens that include PI with conventional pegylated interferon α and ribavirin have significantly improved the sustained virological response (SVR) rate, up to 80% for both treatment-naïve and treatment-experienced patients with HCV genotype 1. We here report for the first time a case of the successful treatment of HCV genotype 1 infection with a first generation PI drug (telaprevir) based triple therapy after treatment failure with a second generation PI drug (vaniprevir) based triple therapy. A 67-year-old treatment-naïve Japanese man with HCV genotype 1b infection took part in a phase III clinical trial of vaniprevir-based triple therapy. His serum HCV RNA had become undetectable at week 2 and SVR was highly expected, but HCV RNA reappeared at week 4 after vaniprevir treatment. Polymerase chain reaction direct sequence of the HCV NS3/4A gene at week 8 after vaniprevir treatment showed the emergence of a vaniprevir-resistance mutation (D168V), the probable reason for the treatment failure. Six months later, retreatment with telaprevir-based triple therapy was started. Although the dosages of telaprevir and ribavirin had to be reduced due to severe anemia, the patient achieved an SVR. This case shows the value of repeating PI-based triple therapy with a different drug, a process that would reduce the chance of drug resistant mutation.

Safety and on-treatment efficacy of telaprevir: the early access programme for patients with advanced hepatitis C

BACKGROUND AND AIM

Severe adverse events (AEs) compromise the outcome of direct antiviral agent-based treatment in patients with advanced liver fibrosis due to HCV infection. HEP3002 is an ongoing multinational programme to evaluate safety and efficacy of telaprevir (TVR) plus pegylated-interferon-α (PEG-IFNα) and ribavirin (RBV) in patients with advanced liver fibrosis caused by HCV genotype 1 (HCV-1).

METHODS

1782 patients with HCV-1 and bridging fibrosis or compensated cirrhosis were prospectively recruited from 16 countries worldwide, and treated with 12 weeks of TVR plus PEG-IFN/RBV, followed by 12 or 36 weeks of PEG-IFN and RBV (PR) alone dependent on virological response to treatment and previous response type.

RESULTS

1587 patients completed 12 weeks of triple therapy and 4 weeks of PR tail (53% cirrhosis, 22% HCV-1a). By week 12, HCV RNA was undetectable in 85% of naives, 88% of relapsers, 80% of partial responders and 72% of null responders. Overall, 931 patients (59%) developed grade 1-4 anaemia (grade 3/4 in 31%), 630 (40%) dose reduced RBV, 332 (21%) received erythropoietin and 157 (10%) were transfused. Age and female gender were the strongest predictors of anaemia. 64 patients (4%) developed a grade 3/4 rash. Discontinuation of TVR due to AEs was necessary in 193 patients (12%). Seven patients died (0.4%, six had cirrhosis).

CONCLUSIONS

In compensated patients with advanced fibrosis due to HCV-1, triple therapy with TVR led to satisfactory rates of safety, tolerability and on-treatment virological response with adequate managements of AEs.

Variants of the inosine triphosphate pyrophosphatase gene are associated with reduced relapse risk following treatment for HCV genotype 2/3

The present study evaluated the impact of variations in the inosine triphosphate pyrophosphatase (ITPase) gene (ITPA) on treatment outcome in patients with hepatitis C virus (HCV) genotype 2/3 infection receiving peginterferon-α2a and lower, conventional 800 mg daily dose of ribavirin. Previous studies using higher, weight-based ribavirin dosing report that patients carrying polymorphisms encoding reduced predicted ITPase activity show decreased risk of ribavirin-induced anemia but increased risk of thrombocytopenia, with no impact on elimination of virus. In all, 354 treatment-naïve HCV genotype 2/3-infected patients, enrolled in a phase III trial (NORDynamIC), were genotyped for ITPA (rs1127354 and rs7270101). Homo- or heterozygosity at Ars1127354 or Crs7270101 , entailing reduced ITPase activity, was observed in 37% of patients and was associated with increased likelihood of achieving sustained virological response (SVR) (P = 0.0003 in univariate and P = 0.0002 in multivariate analyses) accompanied by a reduced risk of relapse among treatment-adherent patients. The association between ITPA variants and SVR remained significant when patients were subdivided by the 12- and 24-week treatment duration arms, HCV genotype, fibrosis stage, and IL28B genotype, and was not secondary to improved adherence to therapy or less pronounced anemia. Gene variants predicting reduced predicted ITPase activity were also associated with decreased risk of anemia (P < 0.0001), increased risk of thrombocytopenia (P = 0.007), and lower ribavirin concentrations (P = 0.02).

CONCLUSION

These findings demonstrate a novel ribavirin-like association between polymorphisms at ITPA and treatment efficacy in chronic hepatitis C mediated by reduced relapse risk. We hypothesize that patients (63%) being homozygous for both major alleles, leading to normal ITPase activity, may benefit more from the addition of ribavirin to present and future treatment regimens for HCV in spite of concomitant increased risk of anemia.

Distribution of genetic polymorphisms associated with hepatitis C virus (HCV) antiviral response in a multiethnic and admixed population

The prevalence of genetic polymorphisms identified as predictors of therapeutic-induced hepatitis C virus (HCV) clearance differs among ethnic groups. However, there is a paucity of information about their prevalence in South American populations, whose genetic background is highly admixed. Hence, single-nucleotide polymorphisms rs12979860, rs1127354 and rs7270101 were characterized in 1350 healthy individuals, and ethnicity was assessed in 259 randomly selected samples. The frequency of rs12979860CC, associated to HCV treatment response, and rs1127354nonCC, related to protection against hemolytic anemia, were significantly higher among individuals with maternal and paternal Non-native American haplogroups (64.5% and 24.2%), intermediate among admixed samples (44.1% and 20.4%) and the lowest for individuals with Native American ancestry (30.4% and 6.5%). This is the first systematic study focused on analyzing HCV predictors of antiviral response and ethnicity in South American populations. The characterization of these variants is critical to evaluate the risk-benefit of antiviral treatment according to the patient ancestry in admixed populations.

Hemoglobin concentration and parasitemia on hospital admission predict risk of multiple organ dysfunction syndrome among adults with malaria

Risk factors for progression from acute malaria to multiple organ dysfunction syndrome (MODS) are poorly understood. The MODS is commonly diagnosed with the sequential organ failure assessment (SOFA) scale, but this scale has been understudied in patients with severe malaria. We conducted a cohort study among 426 adult males admitted to hospital with malaria in Bogotá, Colombia. We estimated SOFA scores and relative risks (RRs) for MODS during hospitalization according to patients' characteristics on admission. Risk of MODS was 7.3% over a median 6.0 days in hospital. Baseline hemoglobin was strongly, inversely associated with MODS (adjusted RR for hemoglobin ≤ 8.5 g/dL versus hemoglobin > 11 g/dL = 9.5, 95% confidence interval [CI]: 3.6, 25.3). Plasmodium falciparum malaria and parasitemia were positively associated with MODS. There was a strong interaction between baseline parasitemia and hemoglobin on MODS risk. In conclusion, the use of parasitemia and hemoglobin on admission to identify high-risk patients deserves consideration.

Review article: genetic factors that modify the outcome of viral hepatitis

BACKGROUND

Genetic factors can play an important role for treatment response and disease progression in chronic viral hepatitis.

AIM

To review the influence of host genetic factors on the clinical course as well as on treatment response in patients with viral hepatitis.

METHODS

Review of the literature.

RESULTS

A landmark genome-wide association study (GWAS) identified polymorphisms in the IL28B gene on chromosome 19 (19q13.13) associated with response to therapy with pegylated interferon-α (PEG-IFN) and ribavirin (RBV) and spontaneous viral clearance in acute hepatitis C. Furthermore, IL28B genotype is associated with changes of lipid metabolism and insulin resistance. A further GWAS demonstrated that ITPA genetic variants protect HCV genotype 1 patients from RBV-induced anaemia. Another polymorphism in the patatin-like phospholipase domain containing 3 (PNPLA3) is associated with hepatic steatosis. Difficult-to-treat hepatitis C patients homozygous for GG had an up to five-fold lower chance of viral clearance on PEG/RBV than non-GG patients. In chronic hepatitis B patients treated with PEG-IFN several retrospective analyses of IL28B rs12980275 and rs12979860 genotypes yielded conflicting results which can be explained by the heterogeneity between the study populations. Some variants of the HLA-DP locus (HLA-DPA1 A allele and HLA-DPB1) protect against progression of chronic hepatitis B infection.

CONCLUSIONS

The determination of IL28B polymorphisms may be useful to individualise treatment options when using PEG/RBV based therapies for chronic hepatitis C infection. In contrast, so far identified genetic factors play only a minor role in chronic hepatitis B infection.

Limited utility of ITPA deficiency to predict early anemia in HCV patients with advanced fibrosis receiving Telaprevir

Background

Severe anemia is a common side effect of Pegylated Interferon + Ribavirin (PR) and Telaprevir (TVR) in hepatitis C virus (HCV) genotype 1 patients with advanced fibrosis or cirrhosis (F3–F4). Inosine triphosphatase (ITPA) genetic variants are associated with RBV- induced anemia and dose reduction.

Aim

To test the association of ITPA polymorphisms rs1127354 and rs7270101 with hemoglobin (Hb) decline, need for RBV dose reduction (RBV DR), erythropoietin (EPO) support and blood transfusions during the first 12 weeks of TVR triple therapy.

Materials and Methods

69 consecutive HCV-1 patients (mean age 57 years) with F3-F4 who received PR and TVR were genotyped for ITPA polymorphisms rs1127354 and rs7270101. Estimated ITPA deficiency was graded on severity (0–3, no deficiency/mild/moderate/severe).

Results

ITPA deficiency was absent in 48 patients (70%), mild in 12 (17%) and moderate in 9 patients (13%). Mean week 4 Hb decline was higher in non ITPA deficient patients (3,85 g/dL) than in mildly or moderately ITPA deficient patients (3,07 g/dL and 1,67 g/dL, p<0.0001). Grade 3–4 anemia developed in 81% non ITPA deficient patients versus 67% mild deficient and 55% moderate deficient patients (p = ns). Grade of ITPA deficiency was not associated with RbvDR (no deficiency: 60%, mild: 58%, moderate: 67%; p = ns), EPO use (no deficiency: 65%, mild: 58%, moderate:56%; p = ns) or need for blood transfusion (no deficiency: 27%, mild: 17%, moderate: 33%; p = ns).

Conclusions

In patients with F3–F4 chronic hepatitis C receiving TVR based therapy, ITPA genotype does not impact on the management of early anemia.

Individualization of chronic hepatitis C treatment according to the host characteristics

Hepatitis C virus (HCV) infection is a global health problem that affects more than 170 million people worldwide. It is a major cause of cirrhosis and hepatocellular carcinoma, making the virus the most common cause of liver failure and transplantation. The standard-of-care treatment for chronic hepatitis C (CHC) has been changed during the last decade and direct acting antiviral drugs have already been used. Besides, understanding of the pathogenesis of CHC has evolved rapidly during the last years and now several host factors are known to affect the natural history and response to treatment. Recent genome-wide association studies have shown the important role of interleukin-28B and inosine triphosphatase in HCV infection. The present review article attempts to summarize the current knowledge on the role of host factors towards individualization of HCV treatment.

A case of successful hepatitis C virus eradication by 24 weeks of telaprevir-based triple therapy for a hemophilia patient with hepatitis C virus/human immunodeficiency virus co-infection who previously failed pegylated interferon-α and ribavirin therapy

In Japan, the human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfection of some patients with hemophilia was caused by the transfusion of imported blood products, such as unheated coagulation factor. With the development of antiretroviral therapy (ART) for HIV, chronic HCV infection has become a major cause of liver disease and mortality for hemophiliac patients coinfected with HCV/HIV. Data is limited regarding the efficacy and safety of antiviral therapy with the HCV protease inhibitor telaprevir (TVR) in combination with pegylated interferon-α (PegIFN-α) and ribavirin (RBV) for hemophilia patients coinfected with HCV/HIV. We report a case of a Japanese patient with hemophilia and HCV/HIV coinfection who had partial response to prior to PegIFN-α and RBV therapy. This is the first published report of 24-week TVR-based triple therapy for a hemophilia patient coinfected with HCV/HIV. The patient had HCV genotype 1a infection with a high viral load. His single-nucleotide polymorphism of the interleukin 28B (rs8099917) gene was the TT major allele. He presented with undetectable HIV RNA and a high CD4(+) T cell counts by taking ART including tenofovir, emtricitabine and raltegravir. He was again treated for HCV with TVR plus PegIFN-α2b and RBV for the first 12 weeks, followed by the continuation of PegIFN-α2b and RBV for 12 additional weeks while continuing ART. He had rapid virological response and achieved sustained virological response with the 24-week treatment. No serious adverse events such as skin rash, severe anemia or exacerbated bleeding tendency were observed, only a mild headache. No dose adjustment was necessary when tenofovir and raltegravir were used in combined with TVR, and no HIV breakthrough was observed. TVR-based triple therapy with ART could can an effective treatment for hemophilia patients coinfected with HCV (genotype 1)/HIV regardless of prior response. TVR can be used in combination with tenofovir, emtricitabine and raltegravir for patients with hemophilia. Furthermore, patients with undetectable HCV RNA at week 4 could be successfully treated with a 24-week regimen.

Influence of low-density lipoprotein cholesterol on virological response to telaprevir-based triple therapy for chronic HCV genotype 1b infection

Elevated serum low-density lipoprotein cholesterol (LDL-C) level has been associated with sustained virological response (SVR) by chronic hepatitis C patients treated with pegylated-interferon (PEG-IFN) α and ribavirin (RBV). The aim of this study was to investigate the relation between the baseline LDL-C level and the treatment outcome from telaprevir (TVR)-based triple therapy. This prospective, multicenter study consisted of 241 treatment-experienced patients infected with HCV genotype 1b. All received 12 weeks of TVR in combination with 24 weeks of PEG-IFNα2b and RBV. The SVR rate was 81.3% (196 of 241) by intention-to-treat analysis. Higher LDL-C level was strongly associated with SVR (P=1.3×10⁻⁸). The area under the receiver operating characteristic curve for predicting SVR was 0.78 and the cutoff value for the LDL-C level at baseline was 95 mg/dL. In multivariable logistic regression analysis of predictors of SVR, LDL-C ≥95 mg/dL (odds ratio [OR] 3.60, P=0.0238), α-fetoprotein ≤5.0 ng/mL (OR 5.06, P=0.0060), prior relapse to PEG-IFNα and RBV (OR 5.71, P=0.0008), and rapid virological response (HCV RNA undetectable at week 4) (OR 5.52, P=0.0010) were extracted as independent predictors of SVR. For prior partial and null responders, the SVR rates of the groups with LDL-C ≥95 mg/dL were significantly higher than those of the <95 mg/dL groups with IL28B TG/GG and pretreatment platelet count <150×10⁹/L (both P<0.05). The baseline LDL-C level exerted a potent influence on the SVR of treatment-experienced patients treated with TVR-based triple therapy, especially for prior partial and null responders to PEG-IFNα and RBV.

Telaprevir-based triple therapy for chronic hepatitis C patients with advanced fibrosis: a prospective clinical study

BACKGROUND

Antiviral treatment is recommended for chronic hepatitis C patients with advanced fibrosis to reduce and prevent cirrhosis-related complications.

AIM

To evaluate the efficacy and safety of telaprevir (TVR)-based triple therapy for patients with advanced fibrosis in a clinical practice setting.

METHODS

This prospective, multicentre study consisted of 102 patients with advanced fibrosis (METAVIR score F3-4) who were infected with HCV genotype 1b. All received 12 weeks of TVR in combination with 24 weeks of pegylated interferon (PEG-IFN) α2b and ribavirin (RBV).

RESULTS

The sustained virological response (SVR) rate was 69.6% (71 of 102). Notably, for treatment-naïve and prior relapse patients the SVR rate was over 80%. Previous treatment response, interleukin 28B polymorphism (rs8099917) and rapid virological response (undetectable HCV RNA at week 4) were independently associated with SVR. To achieve SVR, an adequate dosage of PEG-IFNα2b (≥1.2 μg/kg/week) and RBV (≥7.5 mg/kg/day) is preferable; however, the mean weight-adjusted TVR dosage had little impact on treatment outcome. Although severe blood cytopaenia and a dermatological disorder were frequently found, the rate of discontinuation due to adverse effects was 12.7%. The inosine triphosphatase CC allele (rs1127354) was independently associated with the development of severe anaemia, and lower serum albumin level (<35 g/L) was associated with the occurrence of infection.

CONCLUSIONS

The great gain in the SVR rate by telaprevir-based triple therapy offsets the problems with adverse effects; thus, it should be considered as a potent treatment protocol for patients with advanced fibrosis, especially for those with treatment-naïve and prior relapse.

Therapeutic drug monitoring of telaprevir in chronic hepatitis C patients receiving telaprevir-based triple therapy is useful for predicting virological response

OBJECTIVES

This prospective, pharmacokinetic study was done to investigate the impact of telaprevir plasma trough concentration (Ctrough) in the early stage of treatment on the response to telaprevir-based triple therapy for chronic hepatitis C patients.

METHODS

Participants were 70 chronic hepatitis C patients infected with genotype 1. All patients received 12 week triple therapy that included telaprevir (2250 mg/day), pegylated interferon-α2b (pegylated-IFNα2b) (60-150 μg/week) and ribavirin (600-1000 mg/day) followed by a 12 week dual therapy that included pegylated-IFNα2b and ribavirin. Plasma telaprevir Ctrough was determined by a validated assay using HPLC at days 3, 7 and 14. The study was registered as a clinical trial on the University Hospital Medical Information Network (ID 000009656).

RESULTS

The rates of undetectable hepatitis C virus RNA at week 4 [rapid virological response (RVR)] and at 24 weeks after therapy [sustained virological response (SVR)] were 71.4% and 82.9%, respectively. Of the patients with RVR, 90% achieved SVR. The mean telaprevir Ctrough levels at days 3, 7 and 14 of SVR patients (2.748, 2.733 and 2.999 μg/mL, respectively) were significantly higher than those of non-SVR patients (1.616, 1.788 and 2.314 μg/mL, respectively) (all P < 0.05). Multiple logistic regression analysis of possible predictors of SVR extracted higher telaprevir Ctrough at day 3 (OR 1.012 by 0.001 μg/mL, P < 0.0001) and interleukin 28B (rs8099917) TT allele (OR 6.16 versus non-TT alleles, P < 0.0001).

CONCLUSIONS

Therapeutic drug monitoring of telaprevir in the early stage of treatment is useful in clinical practice for predicting the virological response of patients receiving telaprevir-based triple therapy.