Stuart K. Roberts

Telaprevir for retreatment of HCV infection.

BACKGROUND Up to 60% of patients with hepatitis C virus (HCV) genotype 1 infection do not have a sustained virologic response to therapy with peginterferon alfa plus ribavirin. METHODS In this randomized, phase 3 trial, we evaluated the addition of telaprevir to peginterferon alfa-2a plus ribavirin in patients with HCV genotype 1 infection who had no response or a partial response to previous therapy or who had a relapse after an initial response. A total of 663 patients were assigned to one of three groups: the T12PR48 group, which received telaprevir for 12 weeks and peginterferon plus ribavirin for a total of 48 weeks; the lead-in T12PR48 group, which received 4 weeks of peginterferon plus ribavirin followed by 12 weeks of telaprevir and peginterferon plus ribavirin for a total of 48 weeks; and the control group (PR48), which received peginterferon plus ribavirin for 48 weeks. The primary end point was the rate of sustained virologic response, which was defined as undetectable HCV RNA 24 weeks after the last planned dose of a study drug. RESULTS Rates of sustained virologic response were significantly higher in the two telaprevir groups than in the control group among patients who had a previous relapse (83% in the T12PR48 group, 88% in the lead-in T12PR48 group, and 24% in the PR48 group), a partial response (59%, 54%, and 15%, respectively), and no response (29%, 33%, and 5%, respectively) (P<0.001 for all comparisons). Grade 3 adverse events (mainly anemia, neutropenia, and leukopenia) were more frequent in the telaprevir groups than in the control group (37% vs. 22%). CONCLUSIONS Telaprevir combined with peginterferon plus ribavirin significantly improved rates of sustained virologic response in patients with previously treated HCV infection, regardless of whether there was a lead-in phase. (Funded by Tibotec and Vertex Pharmaceuticals; REALIZE ClinicalTrials.gov number, NCT00703118.).

Oral combination therapy with a nucleoside polymerase inhibitor (RG7128) and danoprevir for chronic hepatitis C genotype 1 infection (INFORM-1): a randomised, double-blind, placebo-controlled, dose-escalation trial

BACKGROUND Present interferon-based standard of care treatment for chronic hepatitis C virus (HCV) infection is limited by both efficacy and tolerability. We assessed the safety, tolerability, and antiviral activity of an all-oral combination treatment with two experimental anti-HCV drugs-RG7128, a nucleoside polymerase inhibitor; and danoprevir, an NS3/4A protease inhibitor-in patients with chronic HCV infection. METHODS Patients from six centres in New Zealand and Australia who were chronically infected with HCV genotype 1 received up to 13 days oral combination treatment with RG7128 (500 mg or 1000 mg twice daily) and danoprevir (100 mg or 200 mg every 8 h or 600 mg or 900 mg twice daily) or placebo. Eligible patients were sequentially enrolled into one of seven treatment cohorts and were randomly assigned by interactive voice or web response system to either active treatment or placebo. Patients were separately randomly assigned within each cohort with a block size that reflected the number of patients in the cohort and the ratio of treatment to placebo. The random allocation schedule was computer generated. Dose escalation was started in HCV treatment-naive patients; standard of care treatment-experienced patients, including previous null responders, were enrolled in higher-dose danoprevir cohorts. Investigators, personnel at the study centre, and patients were masked to treatment allocation. However, the pharmacist who prepared the doses, personnel involved in pharmacokinetic sample analyses, statisticians who prepared data summaries, and the clinical pharmacologists who reviewed the data before deciding to initiate dosing in the next cohort were not masked to treatment allocation. The primary outcome was change in HCV RNA concentration from baseline to day 14 in patients who received 13 days of combination treatment. All patients who completed treatment with the study drugs were included in the analyses. This study is registered with ClinicalTrials.gov, NCT00801255. FINDINGS 88 patients were randomly assigned to a study drug treatment regimen (n=74 over seven treatment groups; 73 received at least one dose of study drug) or to placebo (n=14, all of whom received at least one dose). The median change in HCV RNA concentration from baseline to day 14 ranged from -3·7 to -5·2 log(10) IU/mL in the cohorts that received 13 days of combination treatment. At the highest combination doses tested (1000 mg RG7128 and 900 mg danoprevir twice daily), the median change in HCV RNA concentration from baseline to day 14 was -5·1 log(10) IU/mL (IQR -5·6 to -4·7) in treatment-naive patients and -4·9 log(10) IU/mL in previous standard of care null responders (-5·2 to -4·5) compared with an increase of 0·1 log(10) IU/mL in the placebo group. The combination of RG7128 and danoprevir was well tolerated with no treatment-related serious or severe adverse events, no grade 3 or 4 changes in laboratory parameters, and no safety-related treatment discontinuations. INTERPRETATION This oral combination of a nucleoside analogue polymerase inhibitor and protease inhibitor holds promise as an interferon-free treatment for chronic HCV. FUNDING Roche Palo Alto.

Investigation of the Safety of Irreversible Electroporation in Humans

PURPOSE A single-center prospective nonrandomized cohort study was performed to investigate the safety of irreversible electroporation (IRE) for tumor ablation in humans. MATERIALS AND METHODS Thirty-eight volunteers with advanced malignancy of the liver, kidney, or lung (69 separate tumors) unresponsive to alternative treatment were subjected to IRE under general anesthesia. Clinical examination, biochemistry, and computed tomography (CT) scans of the treated organ were performed before, immediately after, and at 1 month and 3 months after the procedure. RESULTS No mortalities occurred at 30 days. Transient ventricular arrhythmia occurred in four patients, and electrocardiographically (ECG) synchronized delivery was used subsequently in the remaining 30 patients, with two further arrhythmias (supraventricular tachycardia and atrial fibrillation). One patient developed obstruction of the upper ureter after IRE. One adrenal gland was unintentionally directly electroporated, which produced transient severe hypertension. There was no other evidence of adjacent organ damage related to the electroporation. Other adverse events were not directly related to IRE, but two patients developed temporary neurapraxia as a result of arm extension during a prolonged period of anesthesia. Although not a primary aim of this preliminary study, complete target tumor ablation verified by CT was achieved in 46 of the 69 tumors treated with IRE (66%). Most treatment failures occurred in renal and lung tumors. Biopsy in three patients showed coagulative necrosis in the regions treated by IRE. CONCLUSIONS IRE appears to be safe for human clinical use provided ECG-synchronized delivery is used. Comparative evaluation with alternative ablative technologies is warranted.

Faldaprevir and Deleobuvir for HCV Genotype 1 Infection

BACKGROUND Interferon-free regimens would be a major advance in the treatment of patients with chronic hepatitis C virus (HCV) infection. METHODS In this phase 2b, randomized, open-label trial of faldaprevir (a protease inhibitor) and deleobuvir (a nonnucleoside polymerase inhibitor), we randomly assigned 362 previously untreated patients with HCV genotype 1 infection to one of five groups: faldaprevir at a dose of 120 mg once daily and deleobuvir at a dose of 600 mg three times daily, plus ribavirin, for 16, 28, or 40 weeks (TID16W, TID28W, or TID40W, respectively); faldaprevir at a dose of 120 mg once daily and deleobuvir at a dose of 600 mg twice daily, plus ribavirin, for 28 weeks (BID28W); or faldaprevir at a dose of 120 mg once daily and deleobuvir at a dose of 600 mg three times daily, without ribavirin, for 28 weeks (TID28W-NR). The primary end point was a sustained virologic response 12 weeks after the completion of therapy. RESULTS The primary end point was met in 59% of patients in the TID16W group, 59% of patients in the TID28W group, 52% of patients in the TID40W group, 69% of patients in the BID28W group, and 39% of patients in the TID28W-NR group. The sustained virologic response 12 weeks after the completion of therapy did not differ significantly according to treatment duration or dosage among ribavirin-containing regimens. This response was significantly higher with TID28W than with TID28W-NR (P=0.03). Rates of a sustained virologic response 12 weeks after the completion of therapy were 56 to 85% among patients with genotype 1b infection versus 11 to 47% among patients with genotype 1a infection and 58 to 84% among patients with IL28B CC versus 33 to 64% with non-CC genotypes. Rash, photosensitivity, nausea, vomiting, and diarrhea were the most common adverse events. CONCLUSIONS The rate of a sustained virologic response 12 weeks after the completion of therapy was 52 to 69% among patients who received interferon-free treatment with faldaprevir in combination with deleobuvir plus ribavirin. (Funded by Boehringer Ingelheim; SOUND-C2 ClinicalTrials.gov number, NCT01132313.).

Historical epidemiology of hepatitis C virus (HCV) in selected countries

Chronic infection with hepatitis C virus (HCV) is a leading indicator for liver disease. New treatment options are becoming available, and there is a need to characterize the epidemiology and disease burden of HCV. Data for prevalence, viremia, genotype, diagnosis and treatment were obtained through literature searches and expert consensus for 16 countries. For some countries, data from centralized registries were used to estimate diagnosis and treatment rates. Data for the number of liver transplants and the proportion attributable to HCV were obtained from centralized databases. Viremic prevalence estimates varied widely between countries, ranging from 0.3% in Austria, England and Germany to 8.5% in Egypt. The largest viremic populations were in Egypt, with 6 358 000 cases in 2008 and Brazil with 2 106 000 cases in 2007. The age distribution of cases differed between countries. In most countries, prevalence rates were higher among males, reflecting higher rates of injection drug use. Diagnosis, treatment and transplant levels also differed considerably between countries. Reliable estimates characterizing HCV‐infected populations are critical for addressing HCV‐related morbidity and mortality. There is a need to quantify the burden of chronic HCV infection at the national level.

Efficacy and safety of peginterferon alfa‐2a (40KD) plus ribavirin in hepatitis C patients with advanced fibrosis and cirrhosis

The objective of this study is to determine the efficacy and safety of peginterferon alfa‐2a (40KD)/ribavirin in patients with advanced fibrosis. Data from 341 genotype 1/4 patients (99 with bridging fibrosis/cirrhosis) treated for 48 weeks and 1547 genotype 2/3 patients (380 with bridging fibrosis/cirrhosis) treated for 16 or 24 weeks enrolled in three randomized international studies were analyzed. Sustained virological response (SVR) rates decreased progressively from 60% in genotype 1/4 patients without advanced fibrosis to 51% in those with bridging fibrosis and 33% in those with cirrhosis (trend test P = 0.0028); and from 76% to 61% and 57%, respectively, in genotype 2/3 patients treated for 24 weeks (trend test P < 0.0001). Irrespective of genotype, patients without advanced fibrosis were more likely to have an earlier response to treatment that was associated with higher SVR rates and lower relapse rates during untreated follow‐up. Among patients with or without a diagnosis of advanced fibrosis, rates of SVR and relapse were similar for patients with similar responses in the first 12 weeks. Conclusion: Compared with patients with less severe disease, SVR rates are significantly lower in patients with advanced fibrosis. However, irrespective of genotype and degree of fibrosis, the time to become hepatitis C virus (HCV) RNA undetectable was the strongest predictor of SVR. (HEPATOLOGY 2010.)

Tenofovir disoproxil fumarate rescue therapy following failure of both lamivudine and adefovir dipivoxil in chronic hepatitis B

Objective To determine the efficacy of tenofovir disoproxil fumarate (TDF) in adults with chronic hepatitis B virus (HBV) infection who had previously failed lamivudine (LAM) and had significant viral replication (HBV DNA >105 copies/ml if HBeAg positive, >104 copies/ml if HBeAg negative) despite at least 24 weeks of treatment with adefovir dipivoxil (ADV). Design A prospective open-label study of TDF 300 mg daily. Patients receiving combination ADV/LAM prior to baseline were switched to TDF/LAM. Setting Multiple tertiary referral centres. Methods Sixty patients were enrolled. The median age was 48.5 years (range 21–80), 46 (77%) were male and 40 (67%) were HBeAg positive. Thirty-eight patients (63%) were switched from ADV to TDF, the remainder from ADV/LAM to TDF/LAM. At baseline, substitutions conferring resistance to LAM or ADV were present in 20 patients (33%) and 17 patients (28%), respectively. The median baseline viral load was 5.33 log10 IU/ml (range 2.81–8.04). Patients initially treated with TDF monotherapy with persistent viral replication at or after 24 weeks were switched to TDF/LAM. The main outcome measures were change in HBV viral load from baseline and percentage of patients achieving an undetectable viral load (<15 IU/ml). Results Results are reported at 96 weeks of treatment. One patient discontinued TDF at 10 days due to rash. The time-weighted change in viral load from baseline to week 12 was −2.19 log10 IU/ml overall. The median change in HBV DNA from baseline to weeks 12, 24, 48 and 96 was −2.86, −3.23, −3.75 and −4.03 log10 IU/ml, respectively. At 48 and 96 weeks, 27/59 (46%) and 38/59 (64%) patients achieved a HBV DNA <15 IU/ml. The response was independent of baseline LAM therapy or mutations conferring ADV resistance. Conclusions In heavily pretreated patients with a high rate of genotypic resistance, TDF retains significant activity against HBV although this appears diminished in comparison with studies of naïve patients.

Strategies to manage hepatitis C virus (HCV) disease burden

The number of hepatitis C virus (HCV) infections is projected to decline while those with advanced liver disease will increase. A modeling approach was used to forecast two treatment scenarios: (i) the impact of increased treatment efficacy while keeping the number of treated patients constant and (ii) increasing efficacy and treatment rate. This analysis suggests that successful diagnosis and treatment of a small proportion of patients can contribute significantly to the reduction of disease burden in the countries studied. The largest reduction in HCV‐related morbidity and mortality occurs when increased treatment is combined with higher efficacy therapies, generally in combination with increased diagnosis. With a treatment rate of approximately 10%, this analysis suggests it is possible to achieve elimination of HCV (defined as a >90% decline in total infections by 2030). However, for most countries presented, this will require a 3–5 fold increase in diagnosis and/or treatment. Thus, building the public health and clinical provider capacity for improved diagnosis and treatment will be critical.

Efficacy of the Protease Inhibitor BI 201335, Polymerase Inhibitor BI 207127, and Ribavirin in Patients With Chronic HCV Infection

BACKGROUND & AIMS Therapeutic regimens are being developed for patients with hepatitis C virus (HCV) infection that do not include the combination of peginterferon alfa and ribavirin. We investigated the antiviral effect and safety of BI 201335 (an inhibitor of the NS3/4A protease) and BI 207127 (an inhibitor of the NS5B non-nucleoside polymerase) with ribavirin. METHODS Thirty-two treatment-naïve patients with chronic HCV genotype 1 infection were randomly assigned to groups that were given 400 mg or 600 mg BI 207127 3 times daily plus 120 mg BI 201335 once daily and 1000 to 1200 mg/day ribavirin for 4 weeks. The primary efficacy end point was virologic response (HCV RNA level <25 IU/mL at week 4). Thirty-two patients received treatment; 31 completed all 4 weeks of assigned combination therapy. RESULTS In the group given BI 207127 400 mg 3 times daily, the rates of virologic response were 47%, 67%, and 73% at days 15, 22, and 29; a higher rate of response was observed in patients with genotype-1b compared with genotype-1a infections. In the group given BI 207127 600 mg 3 times daily, the rates of virologic response were 82%, 100%, and 100%, respectively, and did not differ among genotypes. One patient in the group given 400 mg 3 times daily had virologic breakthrough (≥1 log(10) rebound in HCV RNA) at day 22. The most frequent adverse events were mild gastrointestinal disorders, rash, and photosensitivity. There were no severe or serious adverse events; no patients discontinued therapy prematurely. CONCLUSIONS The combination of the protease inhibitor BI 201335, the polymerase inhibitor BI 207127, and ribavirin has rapid and strong activity against HCV genotype-1 and did not cause serious or severe adverse events.

D-livering the message: The importance of vitamin D status in chronic liver disease

Vitamin D is synthesized predominantly in the liver and functions as an important secosteroid hormone with pleiotropic effects. While its key regulatory role in calcium and bone homeostasis is well established, recently there is increasing recognition that vitamin D also regulates cell proliferation and differentiation, and has immunomodulatory, anti-inflammatory and anti-fibrotic properties. These non-skeletal effects are relevant in the pathogenesis and treatment of many causes of chronic liver disease. Vitamin D deficiency is frequently present in chronic liver disease and may predict non-response to antiviral therapy in chronic hepatitis C. Small studies suggest that vitamin D supplementation improves sustained viral response rates, while 1α-hydroxylase polymorphisms and vitamin D-binding protein are also implicated in therapeutic outcomes. Vitamin D deficiency also closely relates to the severity of non-alcoholic fatty liver disease (NAFLD) and is implicated in the pathogenesis of insulin resistance, a key factor in the development of NAFLD. In preclinical studies, phototherapy and vitamin D supplementation ameliorate NAFLD histopathology, while vitamin D is a powerful anti-fibrotic against thioacetamide liver injury. In liver transplant recipients severe vitamin D deficiency predicts, and vitamin D supplementation prevents, acute cellular rejection. The role of vitamin D in the activation and regulation of both innate and adaptive immune systems may explain its importance in the above liver diseases. Further prospective studies are therefore warranted to investigate the therapeutic impact of vitamin D supplementation in chronic liver disease.