Silvia Strona

Association of ITPA polymorphisms rs6051702/rs1127354 instead of rs7270101/rs1127354 as predictor of ribavirin-associated anemia in chronic hepatitis C treated patients

Functional variants rs7270101 and rs1127354 of inosine triphosphatase (ITPA) were recently found to protect against ribavirin (RBV)-induced hemolytic anemia. However, no definitive data are yet available on the role of no functional rs6051702 polymorphism. Since a simultaneous evaluation of the three ITPA SNPs for hemolytic anemia has not yet been investigated, we aimed to understand the contribution of each SNPs and its potential clinical use to predict anemia in HCV treated patients. A retrospective analysis included 379 HCV treated patients. The ITPA variants rs6051702, rs7270101 and rs1127354 were genotyped and tested for association with achieving anemia at week 4. We also investigated, using multivariate logistic regression, the impact of each single and paired associated polymorphism on anemia onset. All SNPs were associated with Hb decrease. The carrier of at least one variant allele in the functional ITPA SNPs was associated with a lower decrement of Hb, as compared to patients without a variant allele. In multivariate logistic regression analyses the carrier of a variant allele in the rs6051702/rs1127354 association (OR=0.11, p=1.75×10(-5)) and Hb at baseline (OR=1.51, p=1.21×10(-4)) were independently associated with protection against clinically significant anemia at week 4. All ITPA polymorphisms considered were shown to be significantly associated with anemia onset. A multivariate regression model based on ITPA genetic polymorphisms was developed for predicting the risk of anemia. Considering the characterization of pre-therapy anemia predictors, rs6051702 SNP in association to rs1127354 is more informative in order to avoid this relevant adverse event.

IL28B polymorphism genotyping as predictor of rapid virologic response during interferon plus ribavirin treatment in hepatitis C virus genotype 1 patients

AIM To clarify the association of interleukin-28B (IL28B) single nucleotide polymorphisms (SNPs) with hepatitis C virus (HCV) viremia changes for assessment of interferon (IFN) response. METHODS A cohort of 118 Caucasian treatment-naïve HCV-G1 infected patients, treated with pegylated-IFN alpha 2a or 2b associated with ribavirin (53 responders, 65 non-responders) during the period 2010-2012, were genotyped for IL28B SNPs rs12979860 C>T and rs8099917 T>G. Genotyping was performed by real-time allelic discrimination assay. Serum HCV RNA levels were assayed at 2, 4, 12, 24 and 48 wk during therapy. Correlation between IL28B genotypes and serum HCV RNA kinetics was investigated. Multivariable logistic regression analysis was performed to identify predictors of null-response. RESULTS Twenty-six out of 118 patients (22%) had no HCV RNA decline ≥ 1 log IU/mL at therapy week 4 (null-responders). IL28B genotype was rs8099917 (G)/rs1297860 in 21/26 (80%) of null-responder patients. Using multivariate analysis, it was shown that the presence of the rs8099917 G allele was the best predictor of null-response (OR = 7.9, 95%CI: 1.99-31.18). The presence of at least one favorable genotype showed a positive predictive value of above 90% for HCV RNA reduction ≥ log at week 4. Analysis of the HCV RNA kinetics during 12 wk of therapy in patients with IL28B rs12979860 CT heterozygosis (n = 73), according to their rs8099917 status, showed that the viremia reduction was significantly different in patients carrying the rs8099917 G allele compared to those with favorable homozygosis. CONCLUSION Our findings emphasize the association of the IL28B rs8099917 G allele with HCV. Genotyping for both IL28B SNPs is useful in clinical practice for thorough patient risk stratification based on IFN responsiveness.

Impact of viral eradication with sofosbuvir-based therapy on the outcome of post-transplant hepatitis C with severe fibrosis

Several studies have shown that new direct‐acting antivirals maintain their efficacy in liver transplant (LT) recipients with severe hepatitis C virus (HCV) recurrence. We determined the clinical impact of sofosbuvir/ribavirin in LT through the changes in liver function and fibrosis state at 24 and 48 weeks after treatment.

Telaprevir-S isomer enhances ribavirin exposure and the ribavirin-related haemolytic anaemia in a concentration-dependent manner

The standard-of-care for the treatment of genotype-1 chronic hepatitis C is based on the combination of direct acting antivirals, such as boceprevir and telaprevir, with ribavirin and pegylated-interferon alfa. These triple regimens give a higher response rate than dual therapy, but on the other hand show a more than 10% higher rate of anaemia. Not enough focus has been given to the interaction between telaprevir and RBV. In this work, we aimed to study and deepen this relationship by comparing ribavirin plasma and intra-erythrocytic concentrations at one month of triple and dual therapy (17 vs. 119 patients). Moreover, we determined telaprevir isomers concentrations and tested them for correlation with ribavirin concentrations and haemoglobin loss at one month of treatment. Finally, all drugs concentration data were tested for their correlation with the renal function during treatment. The comparisons of ribavirin concentration and toxicity data were repeated on a sub-group of 9 patients who had been treated 1 year before with dual therapy and then re-treated with triple therapy. The observed ribavirin plasma and intra-erythrocytic concentrations in triple therapy were significantly higher compared to dual therapy, both in whole group and sub-group comparison. Ribavirin concentrations were significantly correlated to the haemoglobin loss and telaprevir-S isomer concentrations (r(2)=0.317 P(value)=0.023 and r(2)=0.388 P(value)=0.008, respectively). Renal function had a significant decrease from the baseline value, but was not significantly correlated with drugs concentrations. These results highlight for the first time that, in the context of triple therapy with telaprevir, ribavirin exposure is related to the telaprevir-S isomer plasma concentration. We conclude that the addition of telaprevir to the dual therapy increases ribavirin exposure and haemoglobin loss: this effect could probably be managed through the therapeutic drug monitoring of ribavirin and telaprevir-S concentrations.

ABCB11 and ABCB1 gene polymorphisms impact on telaprevir pharmacokinetic at one month of therapy

In 2011 direct-acting antivirals, including telaprevir, have been developed to achieve a better antiviral effect. It was reported that telaprevir is a substrate of P-glycoprotein (ABCB1) and cytochrome P450 3A4. The aim of this retrospective study was the evaluation of the influence of some single nucleotide polymorphisms (SNPs) of genes (ABCB1, SLC28A2/3, SLC29A1) involved in TLV and RBV transport and their correlation with plasma TLV drug exposure at 1 month of therapy. We also investigated the association of a SNP in ABCB11 gene, whose role in TLV transport was not yet shown. Twenty-nine HCV-1 patients treated with telaprevir, ribavirin and pegylated-interferon-α were retrospectively analyzed; allelic discrimination was performed by real-time PCR. Telaprevir Ctrough levels were influenced by Metavir score (P=0.023), ABCB1 2677 G>T (P=0.006), ABCB1 1236 C>T (P=0.015) and ABCB11 1131 T>C (P=0.033) SNPs. Regarding ABCB1 3435 C>T, a not statistically significant trend in telaprevir plasma concentration was observed. Metavir score (P=0.002, OR -336; 95% CI -535;-138), ABCB1 2677 (P=0.020, OR 497; 95% CI 86; 910), ABCB11 1131 (P=0.002, OR 641; 95% CI 259;1023) and CNT2 -146 (P=0.006, OR -426; 95% CI -721;-132) were able to predict telaprevir plasma levels in the regression analysis. Other SNPs showed no association. This study reveals BSEP implication in telaprevir transport and confirms the involvement and influence of P-glycoprotein on telaprevir plasma levels. To date, no similar data concerning pharmacogenetics and pharmacokinetics were published, but further studies in different and bigger cohorts are needed.

Negativization of viremia prior to liver transplant reduces early allograft dysfunction in hepatitis C–positive recipients

Although early allograft dysfunction (EAD) negatively impacts survival from the first months following liver transplantation (LT), direct‐acting antiviral agents (DAAs) have revolutionized hepatitis C virus (HCV) therapy. We investigated the EAD definition best predicting 90‐day graft loss and identified EAD risk factors in HCV‐positive recipients. From November 2002 to June 2016, 603 HCV‐positive patients (hepatocellular carcinoma, 53.4%) underwent a first LT with HCV‐negative donors. The median recipient Model for End‐Stage Liver Disease (MELD) score was 15, and the median donor age was 63 years. At LT, 77 (12.8%) patients were HCV RNA negative; negativization was achieved and maintained by pre‐LT antiviral therapy (61 patients) or pre‐LT plus a pre‐emptive post‐LT course (16 patients); 60 (77.9%) patients received DAAs and 17 (22.1%) interferon. We compared 3 different EAD definitions: (1) bilirubin ≥ 10 mg/dL or international normalized ratio ≥ 1.6 on day 7 after LT or aspartate aminotransferase or alanine aminotransferase > 2000 IU/L within 7 days of LT; (2) bilirubin > 10 mg/dL on days 2‐7 after LT; and (3) MELD ≥ 19 on day 5 after LT. EAD defined by MELD ≥ 19 on day 5 after LT had the lowest negative (0.1) and the highest positive (1.9) likelihood ratio to predict 90‐day graft loss. At 90 days after LT, 9.2% of recipients with EAD lost their graft as opposed to 0.7% of those without EAD (P < 0.001). At multivariate analysis, considering variables available at LT, MELD at LT of >25 (OR = 7.4) or 15‐25 (OR = 3.2), graft macrovesicular steatosis ≥ 30% (OR = 6.7), HCV RNA positive at LT (OR = 2.7), donor age > 70 years (OR = 2.0), earlier LT era (OR = 1.8), and cold ischemia time ≥ 8 hours (OR = 1.8) were significant risk factors for EAD. In conclusion, in HCV‐positive patients, MELD ≥ 19 on day 5 after LT best predicts 90‐day graft loss. Preventing graft infection by pre‐/peri‐LT antiviral therapy reduces EAD incidence and could be most beneficial in high‐MELD patients and recipients of suboptimal grafts. Liver Transplantation 23 915–924 2017 AASLD.

Favorable short‐term outcome of hepatitis C virus–positive liver graft with bridging fibrosis: A plea for very early viral eradication

Persistent organ shortage in liver transplantation (LT) forces transplant centers to use extended criteria donors. In this setting, hepatitis C virus (HCV)–positive livers represent a precious resource, but their use has been so far restricted to those with fibrosis stage 2 according to Ishak (i.e., absence of bridging fibrosis), pending studies on fibrosis progression in grafts at more advanced stage. The same indication accrued from our own experience. In 1998 we used a 45-year-old HCV-positive graft having bridging fibrosis (staging 3/6, Ishak) in an HCVpositive recipient, Model for End-stage Liver Disease 19 at LT; cold ischemia time was 689 minutes, and the patient experienced delayed nonfunction (prolonged ascites with progressive cholestasis), requiring re-LT on day 75. However, the recent advent of direct-acting antivirals has revolutionized HCV therapy, and changes in the outcome of HCV-positive grafts can be expected. On December 10, 2015, the number of LTs performed in Turin, Italy, reached 2,771. The donor was a 46-year-old male, deceased of anoxic brain injury. He was HCV-positive, genotype 3a, and inexperienced to antiviral therapy. Abdominal ultrasound showed normal liver and spleen echogenicity and size. Platelet count was 229 3 10/L, with total bilirubin 0.7 mg/ dL, international normalized ratio 1.1, aspartate aminotransferase/alanine aminotransferase 98/171 IU/ L, gamma-glutamyltransferase 297 IU/L, HCV RNA 1,210,101 IU/mL, and hepatitis B virus (HBV) core antibody–positive. On retrieval, the liver was soft despite a grainy capsule (Fig. 1A); biopsy showed fibrous expansion of most portal areas with evidence of portal–portal bridging (grading 4/18, staging 3/6, Ishak) (Fig. 1B,C). The recipient, who signed an informed consent, was a 60-year-old male, affected by HBV/HCV-related cirrhosis (HCV genotype 1b, nonresponder to peginterferon/ribavirin), portal hypertension (large esophageal varices, spleen diameter 20 cm), and multinodular hepatocellular carcinoma beyond San Francisco criteria, successfully downstaged to Milan criteria. At LT, his Model for End-stage Liver Disease score was 8, with creatinine clearance 98 mL/min, HCV RNA 150,656 IU/mL, and HBV DNA undetectable without treatment. Cold ischemia time was 373 minutes; end-to-end biliary anastomosis with T-tube was performed; postreperfusion biopsy showed moderate ischemia–reperfusion injury. Immediate graft function was satisfactory, with no ascites and no evidence of early/delayed dysfunction. Post-LT course was complicated by pneumonia, and he was discharged on day 26. Immunosuppression included tacrolimus, mycophenolate mofetil, and steroids, the last weaned within 6