Sofosbuvir and ribavirin in HCV genotypes 2 and 3

BACKGROUND: In clinical trials, treatment with a combination of the nucleotide polymerase inhibitor sofosbuvir and the antiviral drug ribavirin was associated with high response rates among patients with hepatitis C virus (HCV) genotype 2 infection, with lower response rates among patients with HCV genotype 3 infection. METHODS: We conducted a study involving patients with HCV genotype 2 or 3 infection, some of whom had undergone previous treatment with an interferon-based regimen. We randomly assigned 91 patients with HCV genotype 2 infection and 328 with HCV genotype 3 infection, in a 4:1 ratio, to receive sofosbuvir-ribavirin or placebo for 12 weeks. On the basis of emerging data from phase 3 trials indicating that patients with HCV genotype 3 infection had higher response rates when they were treated for 16 weeks, as compared with 12 weeks, the study was unblinded, treatment for all patients with genotype 3 infection was extended to 24 weeks, the placebo group was terminated, and the goals of the study were redefined to be descriptive and not include hypothesis testing. The primary end point was a sustained virologic response at 12 weeks after the end of therapy. RESULTS: Of the 419 patients who were enrolled and treated, 21% had cirrhosis and 58% had received previous interferon-based treatment. The criterion for a sustained virologic response was met in 68 of 73 patients (93%; 95% confidence interval [CI], 85 to 98) with HCV genotype 2 infection who were treated for 12 weeks and in 213 of 250 patients (85%; 95% CI, 80 to 89) with HCV genotype 3 infection who were treated for 24 weeks. Among patients with HCV genotype 3 infection, response rates were 91% and 68% among those without and those with cirrhosis, respectively. The most common adverse events were headache, fatigue, and pruritus. CONCLUSIONS: Therapy with sofosbuvir-ribavirin for 12 weeks in patients with HCV genotype 2 infection and for 24 weeks in patients with HCV genotype 3 infection resulted in high rates of sustained virologic response. (Funded by Gilead Sciences; VALENCE ClinicalTrials.gov number, NCT01682720.)

Genome Wide Association Study Identifies Genetic Variants Associated With Early And Sustained Response To (Peg)Interferon In Chronic Hepatitis B Patients: The GIANT-B Study

(Peg)interferon ((Peg)IFN) therapy leads to response in a minority of chronic hepatitis B (CHB) patients. Host genetic determinants of response are therefore in demand

Rapid screening by real-time 16S rDNA PCR for bacterial contamination of blood products

Although blood component transfusion is currently regarded as safe, adverse events may occur in recipients of these products. Among those, blood borne viral, bacterial and parasitic infections are best known. For detection of bacterial contamination in platelet concentrates various methods are available or under investigation. One of these methods, real-time polymerase chain reaction (PCR) with particular focus on real-time 16S rDNA detection, will be discussed in this revie

Hepatitis B Virus Pregenomic RNA Is Present in Virions in Plasma and Is Associated With a Response to Pegylated Interferon Alfa-2a and Nucleos(t)ide Analogues

Treatment of patients with chronic hepatitis B (CHB) with nucleos(t)ide analogues (NAs) suppresses hepatitis B virus (HBV) DNA production but does not affect the synthesis of the RNA pregenome or HBV messenger RNA. Whether HBV RNA-containing particles continue to be secreted into the bloodstream remains controversial. We developed a sensitive polymerase chain reaction (PCR) assay to quantify the HBV RNA load in a supernatant of NA-treated HepG2-2.2.15 cells and in plasma specimens from 20 patients with CHB who were receiving NA therapy and 86 patients treated with pegylated interferon alfa (Peg-IFN) and adefovir. Treatment of HepG2-2.2.15 cells with NAs for 9 days reduced HBV DNA levels (by 1.98 log10 copies/mL), whereas HBV RNA levels increased (by 0.47 log10 copies/mL; P < .05). During long-term NA treatment of patients with CHB, HBV RNA levels remained higher than HBV DNA levels. Peg-IFN-based treatment induced a stronger decrease in the HBV RNA load than NA monotherapy, and this decline was more pronounced in responders than in nonresponders. In HBV e antigen-negative patients, a lower baseline plasma HBV RNA level was independently associated with response to Peg-IFN and adefovir (odds ratio, 0.44; P = .019). Immunoprecipitation with HBV core antigen-specific antibodies after removal of the HBV surface antigen envelope demonstrated the association of plasma HBV RNA with virions. HBV RNA is present in virions in plasma specimens from patients with CHB. HBV RNA levels vary significantly from those of established viral markers during antiviral treatment, which highlights its potential as an independent marker in the evaluation of patients with CH

Telaprevir and pegylated interferon-alpha-2a inhibit wild-type and resistant genotype 1 hepatitis C virus replication in patients

Telaprevir (VX-950) is an orally active, specifically targeted antiviral therapy for hepatitis C virus (HCV) that has been shown to profoundly reduce plasma HCV RNA in genotype 1 patients. Using a highly sensitive sequencing assay that detects minor populations of viral variants (>or=5%), mutations were identified that conferred low-level (V36M/A, T54A, or R155K/T) or high-level (A156V/T and 36/155) resistance to telaprevir in vitro. We report a detailed kinetic analysis of these variants in 16 patients given telaprevir or telaprevir + pegylated interferon-alpha-2a (PEG-IFN-alpha-2a) for 14 days. In 4 patients who had a viral rebound on telaprevir alone, the R155K/T and A156V/T variants were detected during the initial steep decline in HCV RNA. During the rebound phase, the R155K/T and A156V/T variants were replaced by V36(M/A)/R155(K/T) double mutant variants. In the remaining 12 patients given telaprevir alone or with telaprevir/PEG-IFN-alpha-2a, the A156V/T variant was detected in some patients, but viral levels continued to decline in all patients. CONCLUSION: These studies suggest that the initial antiviral response to telaprevir is due to a sharp reduction in wild-type virus, which uncovers pre-existing telaprevir-resistant variants. In patients given telaprevir alone, viral rebound can result from the selection of variants with greater fitness. However, the combination of telaprevir and PEG-IFN-alpha-2a inhibited both wild-type and resistant variants. In the present study, every patient who began PEG-IFN-alpha-2a and ribavirin after the 14-day dosing period had undetectable HCV RNA levels at 24 weeks, indicating that telaprevir-resistant variants are sensitive to PEG-IFN-alpha-2a and ribaviri

Deep sequencing identifies hepatitis B virus core protein signatures in chronic hepatitis B patients

Background: We aimed to identify HBc amino acid differences between subgroups of chronic hepatitis B (CHB) patients. Methods: Deep sequencing of HBc was performed in samples of 89 CHB patients (42 HBeAg positive, 47 HBeAg negative). Amino acid types were compared using Sequence Harmony to identify subgroup specific sites between HBeAg-positive and -negative patients, and between patients with combined response and non-response to peginterferon/adefovir combination therapy. Results: We identified 54 positions in HBc where the frequency of appearing amino acids was significantly different between HBeAg-positive and -negative patients. In HBeAg negative patients, 22 positions in HBc were identified which differed between patients with treatment response and those with non-response. The fraction non-consensus sequence on selected positions was significantly higher in HBeAg-negative patients, and was negatively correlated with HBV DNA and HBsAg levels. Conclusions: Sequence Harmony identified a number of amino acid changes associated with HBeAg-status and response to peginterferon/adefovir combination therapy

Rapid decrease of wild-type hepatitis C virus on telaprevir treatment

BACKGROUND: Telaprevir (TVR) is a hepatitis C virus (HCV) NS3.4A protease inhibitor that has exhibited antiviral activity in patients with HCV genotype 1 infection. The viral dynamics in patients dosed with TVR were compared with those reported for patients treated with interferon (IFN). METHODS: The dynamics of wild-type HCV genotype 1 in patients dosed with TVR monotherapy (n=36) and TVR plus pegylated interferon (PEG-IFN)-alpha2a (n=8) were quantified using a biphasic viral dynamic model. RESULTS: Patients dosed with either TVR monotherapy or TVR plus PEG-IFN-alpha2a had median first and second phase decreases of 12 per day and 1.1 per day, respectively. The second phase decrease was approximately 10-fold higher than reported values for IFN-based treatments (P <0.0001). Patients dosed with TVR plus PEG-IFN-alpha2a had a median remaining viral production after blockage (1-epsilon) of -2.37 log(10). In patients dosed with TVR monotherapy, increased TVR dosage of the same schedule was related to better blockage. CONCLUSIONS: These results suggested that TVR-based regimens for chronic HCV infection will lead to an early and more rapid viral decrease that could potentially result in higher sustained viral response rates as well as offer the potential for a reduced duration of treatmen

Emergence of Hepatitis C Virus Genotype 4: Phylogenetic Analysis Reveals Three Distinct Epidemiological Profiles ▿

Hepatitis C virus (HCV) genotype 4 (HCV-4) infection is considered to be difficult to treat and has become increasingly prevalent in European countries, including The Netherlands. Using a molecular epidemiological approach, the present study investigates the genetic diversity and evolutionary origin of HCV-4 in Amsterdam, The Netherlands. Phylogenetic analysis of the NS5B sequences (668 bp) obtained from 133 patients newly diagnosed with HCV-4 infection over the period from 1999 to 2008 revealed eight distinct HCV-4 subtypes; the majority of HCV-4 isolates were of subtypes 4d (57%) and 4a (37%). Three distinct monophyletic clusters were identified, with each one having a specific epidemiological profile: (i) Egyptian immigrants infected with HCV-4a (n = 46), (ii) Dutch patients with a history of injecting drug use infected with HCV-4d (n = 44), and (iii) Dutch human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) infected with HCV-4d (n = 26). Subsequent molecular clock analyses confirmed that the emergence of HCV-4 within these three risk groups coincided with (i) the parenteral antischistosomal therapy campaigns in Egypt (1920 to 1960), (ii) the popularity of injecting drug use in The Netherlands (1960 to 1990), and (iii) the rise in high-risk sexual behavior among MSM after the introduction of highly active antiretroviral therapy (1996 onwards). Our data show that in addition to the influx of HCV-4 strains from countries where HCV-4 is endemic, the local spread of HCV-4d affecting injecting drug users and, in recent years, especially HIV-positive MSM will further increase the relative proportion of HCV-4-infected patients in The Netherlands. HCV-4-specific agents are drastically needed to improve treatment response rates and decrease the future burden of HCV-4-related disease