Phylogenetic and Phylodynamic Analysis of Delta Strains Circulating in Italy.

The hepatitis delta virus (HDV) exhibits high genetic and evolutionary variability and is classified into eight genotypes (HDV-1 to -8). HDV-1 is the most widespread genotype worldwide and includes several subtypes. It predominates mainly in Europe, the Middle East, North America, and Northern Africa, and is associated with both severe and mild forms of liver disease. In this study, we performed phylogenetic and phylodynamic analyses of HDV strains circulating in Regione Lazio, Italy, to understand when these strains were introduced into the Lazio region and to define their genetic variability in Italy. Fifty HDV RNA positive patient samples were amplified using a nested RT-PCR approach targeting the HDV R0 region and sequenced. A phylogenetic tree of patient-derived sequences and reference sequences representing HDV-1 to -8 was constructed using the GTRGAMMA model in RAxML v8. The results indicated that HDV-1 was the predominant genotype with HDV-1d being the most frequently inferred subtype. HDV-1 sequences clustering with subtypes 1b and 1e were also identified. A phylodynamic analysis of HDV-1 sequences employing a Bayesian birth-death model inferred a clock rate of 3.04 × 10-4 substitutions per site per million years, with a 95% Highest Posterior Density (HPD) interval of 3.45 × 10-5 to 5.72 × 10-4. A Bayesian birth-death analysis with tree calibration based on a sample dating approach indicated multiple original sources of infection (from the late 1950s to late 1980s). Overall, these results suggest that HDV sequences from the native Italian and non-Italian patients analyzed in this study represent multiple lineages introduced across a wide period. A common ancestral origin should be excluded.

"Real world" efficacy of bulevirtide in HBV/HDV-related cirrhosis including people living with HIV: Results from the compassionate use programme at INMI Spallanzani in Rome, Italy.

OBJECTIVES: We describe the preliminary results of bulevirtide compassionate use in patients with hepatitis B and delta virus (HBV/HDV)-related cirrhosis and clinically significant portal hypertension, including those living with HIV. METHODS: We conducted a prospective observational study of consecutive patients. Clinical evaluation, liver function tests, bile acid levels, HDV-RNA, HBV-DNA, hepatitis B surface antigen, and liver and spleen stiffness were assessed at baseline and after treatment months 1, 2, 3, 4, 6, 9, and 12. HIV-RNA and CD4+/CD8+ count were assessed in people living with HIV. The first drug injection was administered under nurse supervision, and counselling was provided and adherence reviewed at each visit. RESULTS: In total, 13 patients (61.5% migrants) were enrolled. The median treatment duration was 11 months. At month 6, mean alanine aminotransferase (ALT) levels fell by 64.5% and mean liver and spleen stiffness decreased by 8.6 and 0.9 kPa, respectively. The mean baseline HDV-RNA was 3.34 log IU/mL and 5.10 log IU/mL in people without and with HIV (n = 5) (p = 0.28), respectively. A similar mean decline was observed in both groups: -2.06 log IU/mL and -1.93 log IU/mL, respectively (p = 0.87). A combined response (undetectable HDV RNA or ≥ -2 log IU/mL decline vs. baseline, with ALT normalization) was achieved in 66% of subjects without and in 60% of patients with HIV. Patients with HIV showed persistently undetectable HIV-RNA and a progressive increase in CD4+/CD8+ cells during treatment. No patient discontinued bulevirtide because of adverse effects. CONCLUSIONS: Preliminary results suggest that bulevirtide is feasible and well-tolerated in populations with difficult-to-treat conditions, such as those with HIV/HBV/HDV co-infection and migrants, when special attention is given to patient education. HDV-RNA decline during treatment was similar in people living with and without HIV.

Humoral Immune Response after COVID-19 mRNA Vaccination in Patients with Liver Cirrhosis: A Prospective Real-Life Single Center Study.

Coronavirus-disease-2019 (COVID-19) mRNA vaccination effectively reduces mortality and morbidity in cirrhotic patients, but the immunogenicity and safety of vaccination have been partially characterized. The study aimed to evaluate humoral response, predictive factors, and safety of mRNA-COVID-19 vaccination in cirrhotic patients compared to healthy subjects. A prospective, single-center, observational study enrolled consecutive cirrhotic patients who underwent mRNA-COVID-19 vaccination from April to May 2021. Anti-spike-protein (anti-S) and nucleocapsid-protein (anti-N) antibodies were evaluated before the first (T0) and the second (T1) doses and 15 days after completing the vaccination. An age and sex-matched healthy reference group was included. The incidence of adverse events (AEs) was assessed. In total, 162 cirrhotic patients were enrolled, 13 were excluded due to previous SARS-CoV-2 infection; therefore, 149 patients and 149 Health Care Workers (HCWs) were included in the analysis. The seroconversion rate was similar in cirrhotic patients and HCWs at T1 (92.5% vs. 95.3%, p = 0.44) and T2 (100% in both groups). At T2, anti-S-titres were significantly higher in cirrhotic patients compared to HCWs (2776.6 vs. 1756 BAU/mL, p < 0.001]. Male sex (ß = -0.32 [-0.64, -0.04], p = 0.027) and past-HCV-infection (ß = -0.31 [-0.59, -0.04], p = 0.029) were independent predictors of lower anti-S-titres on multiple-gamma-regression-analysis. No severe AEs occurred. The COVID-19-mRNA vaccination induces a high immunization rate and anti-S-titres in cirrhotic patients. Male sex and past-HCV infection are associated with lower anti-S-titres. The COVID-19-mRNA vaccination is safe.

Third dose of SARS-CoV2 mRNA vaccination produces robust persistent cellular and humoral immune responses in liver transplant recipients.

Weaker responses have been described after two doses of anti-SARS-CoV2 vaccination in liver transplant recipients (LTRs). At the Italian National Institute for Infectious Diseases, 122 LTRs (84% males, median age 64 years) were tested for humoral and cell-mediated immune response after a third doses of anti-SARS-CoV2 mRNA vaccines. Humoral response was measured by quantifying anti-receptor binding domain and neutralizing antibodies; cell-mediated response was measured by quantifying IFN-γ after stimulation of T cells with SARS-CoV-2-specific peptides. Humoral and cellular responses improved significantly compared to the second vaccine dose; 86.4% of previous non-responders to the first 2 vaccine doses (N = 22) became responders. Mycophenolate mofetil-containing regimens were not associated with lower response rates to a third vaccine; shorter time since transplantation (<6 years) was associated with lower humoral and cellular responses to third vaccine. Protective antibodies against Omicron variant were detected in 60% of patients 12 weeks after third vaccine dose.

Analysis of HIV quasispecies and virological outcome of an HIV D+/R+ kidney-liver transplantation.

INTRODUCTION: Transplantation among HIV positive patients may be a valuable therapeutic intervention. This study involves an HIV D+/R+ kidney-liver transplantation, where PBMC-associated HIV quasispecies were analyzed in donor and transplant recipients (TR) prior to transplantation and thereafter, together with standard viral monitoring. METHODS: The donor was a 54 year of age HIV infected woman: kidney and liver recipients were two HIV infected men, aged 49 and 61. HIV quasispecies in PBMC was analyzed by ultra-deep sequencing of V3 env region. During TR follow-up, plasma HIV-1 RNA, HIV-1 DNA in PBMC, analysis of proviral integration sites and drug-resistance genotyping were performed. Other virological and immunological monitoring included CMV and EBV DNA quantification in blood and CD4 T cell counts. RESULTS: Donor and TR were all ART-HIV suppressed at transplantation. Thereafter, TR maintained a nearly suppressed HIV-1 viremia, but HIV-1 RNA blips and the increase of proviral integration sites in PBMC attested some residual HIV replication. A transient peak in HIV-1 DNA occurred in the liver recipient. No major changes of drug-resistance genotype were detected after transplantation. CMV and EBV transient reactivations were observed only in the kidney recipient, but did not require specific treatment. CD4 counts remained stable. No intermixed quasispecies between donor and TR was observed at transplantation or thereafter. Despite signs of viral evolution in TR, HIV genetic heterogeneity did not increase over the course of the months of follow up. CONCLUSIONS: No evidence of HIV superinfection was observed in the donor nor in the recipients. The immunosuppressive treatment administrated to TR did not result in clinical relevant viral reactivations.

Coordinated cellular and humoral immune responses after two-dose SARS-CoV2 mRNA vaccination in liver transplant recipients.

Limited data are available on risks and benefits of anti-SARS-CoV2 vaccination in solid organ transplant recipients, and weaker responses have been described. At the Italian National Institute for Infectious Diseases, 61 liver transplant recipients underwent testing to describe the dynamics of humoral and cell-mediated immune response after two doses of anti-SARS-CoV2 mRNA vaccines and compared with 51 healthy controls. Humoral response was measured by quantifying both anti-spike and neutralizing antibodies; cell-mediated response was measured by PBMC proliferation assay with IFN-γ and IL-2 production. Liver transplant recipients showed lower response rates compared with controls in both humoral and cellular arms; shorter time since transplantation and multi-drug immunosuppressive regimen containing mycophenolate mofetil were predictive of reduced response to vaccination. Specific antibody and cytokine production, though reduced, were highly correlated in transplant recipients.

High prevalence of asymptomatic SARS-CoV-2 infection in a cohort of liver transplant recipients in central Italy.

Asymptomatic subjects account for 25 to 45% of SARS-CoV-2 infections, and in particular, subjects on mild immunosuppressive therapy may have symptoms masked and could spread virus for an extended period of time. To determine the cumulative incidence of symptomatic and asymptomatic SARS-CoV-2 infections and associated risk factors, we conducted a prospective clinical and serological survey in a cohort of 278 liver transplant recipients (LTRs) from Central Italy. Three different serology tests were performed every 4 months in 259 LTRs between April 2020 and April 2021: one based on raw extract of whole SARS-CoV-2 virus and two on specific viral antigens (nucleoprotein and receptor binding domain) to detect specific IgG, IgM and IgA. Hundred fifteen LTRs who reported symptoms or close contact with a SARS-CoV-2-positive subject, or had a positive serological result underwent molecular testing by standard screening procedures (RT-PCR on naso-pharyngeal swab). Thirty-one past or active SARS-CoV-2 infections were identified: 14 had positive molecular test (64% symptomatic), and 17 had positive serology only (18% symptomatic). SARS-CoV-2 infection was not statistically related to gender, age, obesity, diabetes, renal impairment, type of anti-rejection therapy or time from transplant. Asymptomatic SARS-CoV-2 cases (61.3%) were more frequent in males and in those with glomerular filtrate rate >50 ml/min. Overall, the addition of repeated serology to standard diagnostic molecular protocols increased detection of SARS-CoV-2 infection from 5.1% to 10.9%. Anti-SARS-CoV-2 seroprevalence among our LTRs (11.2%) is comparable to the general population of Central Italy, considered a medium-impact area. Only one asymptomatic subject (6%) was found to carry SARS-CoV-2 in respiratory tract at the time of serological diagnosis.

Liver transplantation from active COVID-19 donors: A lifesaving opportunity worth grasping?

COVID-19 pandemic dramatically impacted transplantation landscape. Scientific societies recommend against the use of donors with active SARS-CoV-2 infection. Italian Transplant Authority recommended to test recipients/donors for SARS-CoV-2-RNA immediately before liver transplant (LT) and, starting from November 2020, grafts from deceased donors with active SARS-CoV-2 infection were allowed to be considered for urgent-need transplant candidates with active/resolved COVID-19. We present the results of the first 10 LTs with active COVID-19 donors within an Italian multicenter series. Only two recipients had a positive molecular test at LT and one of them remained positive up to 21 days post-LT. None of the other eight recipients was found to be SARS-CoV-2 positive during follow-up. IgG against SARS-CoV-2 at LT were positive in 80% (8/10) of recipients, and 71% (5/7) showed neutralizing antibodies, expression of protective immunity related to recent COVID-19. In addition, testing for SARS-CoV-2 RNA on donors' liver biopsy at transplantation was negative in 100% (9/9), suggesting a very low risk of transmission with LT. Immunosuppression regimen remained unchanged, according to standard protocol. Despite the small number of cases, these data suggest that transplanting livers from donors with active COVID-19 in informed candidates with SARS-CoV-2 immunity, might contribute to safely increase the donor pool.

Clinical Relevance of Torque Teno Virus (TTV) in HIV/HCV Coinfected and HCV Monoinfected Patients Treated with Direct-Acting Antiviral Therapy.

Torque Teno virus (TTV) is a ubiquitous virus that causes chronic infection in humans with unknown clinical consequences. Here, we investigated the influence of TTV infection on HCV direct-acting antiviral (DAA) efficacy in HIV/HCV coinfected and HCV monoinfected patients as controls. Of 92 study patients, 79.3% were TTV DNA positive; untreated patients exhibited a significantly higher proportion of TTV DNA-positivity vs. sustained virological response (SVR) patients (100.0% vs. 65.2%, p < 0.001), while TTV positivity was not significant in DAA failure patients vs. SVR patients despite HIV/HCV coinfection. TTV DNA viral load was higher among HCV monoinfected patients vs. HIV/HCV coinfected, although marginally significant (p = 0.074) and no significant viral load difference was detected between DAA failures and SVR patients, while untreated vs. SVR patients had a significantly higher viral load (19,884, IQR 5977-333,534, vs. 469, IQR 10-4124, p = 0.004). Alpha-genogroup 3 TTV was the most prevalent genetic group, and no specific strain or genogroup was observed in relapser patients. Among HIV/HCV patients with HCV RNA detectable at end of treatment (EOT), TTV DNA was detected in 9/17 treatment responder patients and 3/5 relapser patients, thus, TTV infection does not appear to influence the control HCV viremia after EOT. Levels of IL-6 IL-4, and CD14 were not significantly different between TTV PCR-positive and -negative patients. These results suggest no association between TTV DNA positivity or viral load and HCV DAA failure whether patients were HIV/HCV coinfected or HCV monoinfected.

Hepatic Failure in COVID-19: Is Iron Overload the Dangerous Trigger?

Liver injury in COVID-19 patients has progressively emerged, even in those without a history of liver disease, yet the mechanism of liver pathogenicity is still controversial. COVID-19 is frequently associated with increased serum ferritin levels, and hyperferritinemia was shown to correlate with illness severity. The liver is the major site for iron storage, and conditions of iron overload have been established to have a pathogenic role in development of liver diseases. We presented here six patients who developed severe COVID-19, with biochemical evidence of liver failure. Three cases were survived patients, who underwent liver biopsy; the other three were deceased patients, who were autopsied. None of the patients suffered underlying liver pathologies. Histopathological and ultrastructural analyses were performed. The most striking finding we demonstrated in all patients was iron accumulation into hepatocytes, associated with degenerative changes. Abundant ferritin particles were found enclosed in siderosomes, and large aggregates of hemosiderin were found, often in close contact with damaged mitochondria. Iron-caused oxidative stress may be responsible for mitochondria metabolic dysfunction. In agreement with this, association between mitochondria and lipid droplets was also found. Overall, our data suggest that hepatic iron overload could be the pathogenic trigger of liver injury associated to COVID-19.

The impact of the coronavirus disease 2019 pandemic on a central Italy transplant center.

Coronavirus disease 2019 (COVID-19) is challenging health care systems worldwide, raising the question of reducing the transplant program due to the shortage of intensive care unit beds and to the risk of infection in donors and recipients.We report the positive experience of a single Transplant Center in Rome, part of the National Institute for Infectious Diseases Lazzaro Spallanzani, one of the major national centers involved in the COVID-19 emergency.

Publisher Correction: Liver sinusoidal endothelial cells (LSECs) modifications in patients with chronic hepatitis C.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Liver sinusoidal endothelial cells (LSECs) modifications in patients with chronic hepatitis C.

The sinusoidal endothelial cells present in the liver (LSECs) are tipically characterized by the presence of pores (fenestrae). During some pathological conditions LSECs undergo "capillarization", a process characterized by loss of fenestrations and acquisition of a vascular phenotype. In chronic liver disease capillarization has been reported to precede the development of fibrosis. LSECs modification in the setting of HCV infection is currently poorly investigated. Considering that HCV accounts for important changes in hepatocytes and in view of the intimate connection between hepatocytes and LSECs, here we set out to study in great detail the LSECs modifications in individuals with HCV-dependent chronic hepatitis. Electron microscopy analysis, and evaluation of CD32, CD31 and caveolin-1 expression showed that in HCV infection LSECs display major morphological changes but maintain their phenotypical identity. Capillarization was observed only in cases at initial stages of fibrosis. Our findings showed that the severity of LSECs modifications appears to be correlated with hepatocytes damage and fibrosis stage providing novel insight in the pathogenesis of HCV-chronic hepatitis.

Daclatasvir, sofosbuvir with or without ribavirin for 24 weeks in hepatitis C genotype 3 cirrhosis: A real-life study.

INTRODUCTION AND AIM: Cirrhotic patients with hepatitis C virus genotype 3 infection show unsatisfactory outcomes after 12 weeks' treatment with direct antiviral agents. The National Italian Drug Agency allows 24 weeks of therapy in difficult-to-treat patients, including genotype 3 cirrhotics. Aim of this study was to evaluate efficacy and safety of a 24-week course of sofosbuvir plus daclatasvir±ribavirin in this population. MATERIALS AND METHODS: 106 consecutive cirrhotics (70.8% males, mean age 55.3±7.6 years) in 8 tertiary hepatology centers received sofosbuvir plus daclatasvir for 24 weeks. Ribavirin was administered in 85 (80.2%) based expected tolerability, at a mean dose of 964±202mg/day. Baseline Child-Pugh class was A 91.5%, B 6.6%, C 1.9%; mean baseline MELD was 8.5±2.7. RESULTS: All patients completed 12-week follow-up post-treatment, and 104 (98.1%) obtained sustained virological response (100% in ribavirin -treated patients vs. 90.4% without ribavirin; p=0.04). No worsening in renal and liver function was observed, no serious adverse events occurred. Two virological failures showed resistance associated variants (Y93H and S282T). CONCLUSION: An extended 24-week treatment with sofosbuvir plus daclatasvir+ribavirin obtained 100% efficacy in genotype 3 hepatitis C cirrhosis, with very limited side effects. The role of ribavirin seems crucial in this setting and should be administered if clinically feasible.

Unawareness of HCV serostatus among persons newly diagnosed with HIV.

Treatment of chronic HCV infection with direct acting antivirals can achieve high rates of sustained viral response in persons with HIV. In the perspective of HCV elimination in this population, high rates of HCV detection will be needed. We evaluated the unawareness of HCV infection in 2927 persons newly diagnosed with HIV during 2004-2015 in Rome, Italy. Two-hundred-fifty persons (8.5%) were anti-HCV positive. The proportion of HCV-unaware individuals at the time of HIV diagnosis was 58.0% (145/250), without significant variations over time, 17.2% showed an advanced fibrosis stage. The absence of previous HIV testing was significantly associated with HCV unawareness.

Lack of reduction in serum alpha-fetoprotein during treatment with direct antiviral agents predicts hepatocellular carcinoma development in a large cohort of patients with hepatitis C virus-related cirrhosis.

Risk of hepatocellular carcinoma (HCC) in hepatitis C virus cirrhotic patients treated with direct-acting antiviral agents (DAA) is still debating. We investigated it in a large cohort. The cohort comprised 1045 cirrhotic patients who completed treatment with DAA, with a median follow-up of 17.3 months after end of treatment (EOT), including 943 patients without history of HCC and 102 previously treated for HCC. The majority were men (59.9%), with compensated cirrhosis (88.8%), genotype 1b (44.7%). Univariate, multivariate analysis and Kaplan-Meier curves were performed to detect predictors of HCC in patients with and without reduction in alpha-fetoprotein (AFP) during treatment. SVR12 was 95.6%. HCC developed in 95 (9.9%), including 54 of 943 (5.7%) occurrent and 41 of 102 (39%) recurrent tumours. De novo were more often unifocal (P = 0.01) and curable (P = 0.03). AFP decreased from 16.1 ± 36.2 mg/dL (baseline) to 11.4 ± 55 mg/dL (EOT). At univariate analysis, predictors were a previous HCC, older age, higher model for end-stage liver disease, prolonged INR, lower platelets, baseline and EOT AFP, virological failure and no reduction in AFP during treatment. Kaplan-Meier curves showed lower incidence of HCC in patients showing any reduction in AFP (P = 0.001). Those with AFP <6 ng/mL had the lowest risk (P = 0.0002). At logistic regression, platelets (P = 0.009, OR 0.99 CI: 0.99-1.00), previous HCC (P < 0.000 01, OR: 10.76, 95% CI: 5.89-19.34) and no reduction in AFP during treatment (P = 0.0005, OR: 2.98, CI: 1.60-5.54) were independent predictors of HCC. In conclusion, risk of HCC after DAA treatment remains substantial. It is higher among patients with previous HCC, low platelets and without reduction in AFP during treatment.

Significance of detectable HCV RNA below the limit of quantification in patients treated with DAAs using standard and ultrasensitive protocols.

Predictive factors of HCV relapse after treatment with DAAs are poorly understood. In this study, we aimed to assess whether the residual viral load positivity observed during or at the end of treatment (EOT) has an impact on viral outcome. Blood samples were collected from 337 patients with genotypes (GT) 1a, 1b, 2, 3, and 4 HCV chronic infection, treated with DAAs to determine HCV RNA load by the Abbott RealTime HCV (ART) assay at treatment week (W) 4, at EOT, and 4, 12, 24 weeks after discontinuation. EOT and other samples with "detected <12/mL" (DNQ) were retested by an ultrasensitive protocol (USP) to confirm the result. Frequency of DNQ was analyzed in subgroups of patients and clinical conditions to assess potential correlations. At W4, 22% and 30.9% of the samples were undetectable and DNQ by ART assay, respectively, but no correlation for achieving SVR was found. In contrast, an HCV RNA cut-off of ≥50/mL at W4 was a significant predictor of therapy failure (P = 0.036, univariate analysis). At EOT, DNQ was associated to 12W treatment duration (P < 0.001) and GT1a infection (P = 0.036). Overall, 20/41 (48.8%) of DNQ samples at EOT or post-treatment W4, were confirmed by USP but only in a single case the patient experienced viral relapse. HCV RNA at W4 can predict SVR, irrespective to genotype or DAA regimen. HCV RNA DNQ at EOT is associated to shorter treatment duration and to GT1a, but is not a predictor of therapy failure.

The Italian compassionate use of sofosbuvir in HCV patients waitlisted for liver transplantation: A national real-life experience.

BACKGROUND & AIMS: This study aimed to assess the real-life clinical and virological outcomes of HCV waitlisted patients for liver transplantation (LT) who received sofosbuvir/ribavirin (SOF/R) within the Italian compassionate use program. METHODS: Clinical and virological data were collected in 224 patients with decompensated cirrhosis and/or hepatocellular carcinoma (HCC) receiving daily SOF/R until LT or up a maximum of 48 weeks. RESULTS: Of 100 transplanted patients, 51 were HCV-RNA negative for >4 weeks before LT (SVR12: 88%) and 49 negative for <4 weeks or still viraemic at transplant: 34 patients continued treatment after LT (bridging therapy) (SVR12: 88%), while 15 stopped treatment (SVR12: 53%). 98 patients completed SOF/R without LT (SVR12: 73%). In patients with advanced decompensated cirrhosis (basal MELD ≥15 and/or C-P ≥B8), a marked improvement of the scores occurred in about 50% of cases and almost 20% of decompensated patients without HCC reached a condition suitable for inactivation and delisting. CONCLUSIONS: These real-life data indicate that in waitlisted patients: (i) bridging antiviral therapy can be an option for patients still viraemic or negative <4 weeks at LT; and (ii) clinical improvement to a condition suitable for delisting can occur even in patients with advanced decompensated cirrhosis.

Sofosbuvir plus daclatasvir with or without ribavirin is safe and effective for post-transplant hepatitis C recurrence and severe fibrosis and cirrhosis: A prospective study.

BACKGROUND: In 2012, an Italian Named Patient Program began for hepatitis C virus (HCV)-infected liver transplant (LT) recipients with advanced fibrosis, before approval of direct antiviral agents (DAA), to benefit severely ill patients. The aim of this "real-life" study was to assess treatment efficacy and safety with an extended course of daclatasvir (DCV) plus sofosbuvir (SOF) with or without ribavirin (RBV). METHODS: All HCV LT recipients with severe fibrosis in 15 Italian transplant centers were treated with DCV+SOF±RBV for 24 weeks; sustained virological response was assessed at 12 weeks post-treatment (SVR12). RESULTS: Eighty-seven patients were enrolled (75.9% males, mean age 58.4 ± 7.2 years, 83.9% genotype 1, 81.6% cirrhosis); 52 (59.8%) received RBV. Overall, 79 obtained SVR12 (90.8%): 100% in F3 and 88.7% in cirrhotics (91.5% in Child-Pugh A, 83.3% in Child-Pugh B and C). According to the treatment group, SVR was 80% in DCV + SOF group and 98.1% in SOF + DCV + RBV. Two virological relapses occurred during follow-up in cirrhotic patients who received DCV + SOF. Four cirrhotic patients in DCV + SOF group and 1 in DCV + SOF + RBV group died on treatment. CONCLUSION: An extended course of SOF plus DCV for 24 weeks, with or without RBV, is effective and well tolerated for the treatment of post-LT HCV recurrence with severe fibrosis.

Characterization of Naturally Occurring NS5A and NS5B Polymorphisms in Patients Infected with HCV Genotype 3a Treated with Direct-Acting Antiviral Agents.

Hepatitis C virus (HCV) genotype (GT)3 is associated with increased risk of steatosis, development of cirrhosis and hepatocellular carcinoma. Limited data are available regarding genetic variability and use of direct-acting antiviral agents in these patients. non-structural protein 5A (NS5A) and non-structural protein 5B (NS5B) sequencing was performed on 45 HCV GT3-infected Italian patients subsequently treated with sofosbuvir ± daclatasvir (SOF ± DCV). Novel GT3a polymorphisms were observed by Sanger sequencing in three NS5A (T79S, T107K, and T107S) and three NS5B (G166R, Q180K, and C274W) baseline sequences in patients who achieved sustained virological response (SVR). Baseline NS5A resistance-associated substitutions A30K and Y93H were detected in 9.5% of patients; one patient with A30K did not achieve SVR. Phylogenetic analyses of sequences showed no distinct clustering. Genetic heterogeneity of NS5A and NS5B was evaluated using ultra-deep pyrosequencing (UDPS) in samples longitudinally collected in patients not achieving SVR. Some novel NS5A and NS5B polymorphisms detected at baseline may not impact treatment outcome, as they were not enriched in post-failure samples. In contrast, the novel L31F NS5A variant emerged in one treatment failure, and I184T, G188D and N310S, located on the same NS5B haplotype, became predominant after failure. These findings suggest a potential impact of these novel substitutions on the treatment outcome; however, their significance requires further investigation.