Faculty Bibliography

BACKGROUND & AIMS: HCV genotype, subtype, and presence of resistance-associated substitutions (RASs) are key determinants for the selection of direct-acting antiviral (DAA) treatment regimens. However, current HCV genotyping assays have limitations in differentiating between HCV subtypes, and RAS prevalence is largely undefined. The aim of this study was to investigate HCV epidemiology in 12,615 patient samples from 28 different countries across five geographic regions. METHODS: We compared HCV genotype and subtypes using INNO-LiPA 2.0 vs. amplicon sequencing among 8,945 patients from phase II/III clinical trials of DAAs. Global HCV molecular epidemiology in 12,615 patients was investigated. Subtype RAS prevalence was determined by population or deep sequencing, and phylogenetic analyses investigating subtype diversity were performed. RESULTS: Although there was high concordance between INNO-LiPA and sequencing for genotype determination, INNO-LiPA was insufficient for subtype determination for genotype 2, 3, 4, and 6. Sequencing provided subtype refinement for 42%, 10%, 81%, and 78% of genotype 2, 3, 4, and six patients, respectively. Genotype discordance (genotype 2-genotype 1) was observed in 28 of 950 (3%) genotype 2 patients, consistent with inter-genotype recombinants. Sequencing-based analyses demonstrated variations in regional subtype prevalence, notably within genotype 2, 4 and 6. RAS prevalence varied by subtype, with the clinically relevant NS3 RAS Q80K found in genotype 1a, 5a and 6a and the NS5A RAS Y93H in genotype 1b, 3a, 4b, 4r and 7. CONCLUSIONS: Together, these analyses provide an understanding of subtyping accuracy and RAS distribution that are crucial for the implementation of global HCV treatment strategies. LAY SUMMARY: Hepatitis C virus (HCV) is highly variable, with seven genotypes and 67 subtypes characterized to date. The aim of this study was to i) compare two different methods of discriminating between genotypes; ii) investigate the prevalence of HCV subtypes for each genotype around the world; iii) find the prevalence of resistance-associated substitutions (RASs) in different subtypes. We found that both methods showed high concordance in genotype discrimination, but specific subtypes were not always identified accurately. Sequencing-based analyses demonstrated variations in regional subtype prevalence for some genotypes, notably within GT2, 4 and 6. RAS prevalence also varied by subtype. These variations could determine how successful different drugs are for treating HCV.

BACKGROUND & AIM: Despite complete suppression of viral DNA with antiviral agents, in some patients with chronic hepatitis B (CHB), serum levels of alanine aminotransferase (ALT) do not normalize. We investigated factors associated with persistent increases in level of ALT in patients with CHB given long-term tenofovir disoproxil fumarate. METHODS: We analyzed data from 471 hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients with CHB participating in 2 phase 3 trials. We identified patients with an increased level of ALT (above the upper limit of normal range) after 5 years (240 weeks) of tenofovir disoproxil fumarate therapy. We analyzed findings from liver biopsies collected from 467 patients (99%) at baseline and 339 patients (72%) at year 5 of treatment; biopsies were evaluated by an independent pathologist. We performed stepwise, forward, multivariate regression analyses of specified baseline characteristics and on-treatment response parameters to identify factors associated with persistent increases in level of ALT. RESULTS: Of the 471 patients, 87 (18%) still had an increased level of ALT at year 5 of treatment. Factors independently associated with persistent increase in level of ALT were steatosis score of 5% or more (grade 1 or more) at baseline (odds ratio [OR], 2.224; 95% CI, 1.031-4.852; P=.042) and at year 5 (OR, 3.39; 95% CI 1.560>/=7.375; P=.002), HBeAg seropositivity at baseline (OR, 3.30; 95% CI, 1.653-6.576; P<.001), and age of 40 years or more (OR, 2.10; 95% CI, 1.014-4.342; P=.046). Of the 42 HBeAg-positive patients with steatosis at baseline, 21 (50%) had an increased level of ALT at year 5 of treatment. Patients with persistent increases in ALT were more likely to have an increase in steatosis at year 5 than those with a normal level of ALT. CONCLUSION: HBeAg seropositivity and hepatic steatosis contribute to persistent increases in level of ALT in patients with CHB receiving suppressive antiviral treatment. ClinicalTrials.gov no: NCT00116805.

BACKGROUND & AIMS: Patients with chronic hepatitis C virus (HCV) infection have high rates of sustained virologic response (SVR) following 12 weeks of treatment with the nucleotide polymerase inhibitor sofosbuvir combined with the NS5A inhibitor velpatasvir. We assessed the efficacy of 8 weeks of treatment with sofosbuvir and velpatasvir plus the pangenotypic NS3/4A protease inhibitor voxilaprevir (sofosbuvir-velpatasvir-voxilaprevir). METHODS: In 2 phase 3, open-label trials, patients with HCV infection who had not previously been treated with a direct-acting antiviral agent were randomly assigned to groups given sofosbuvir-velpatasvir-voxilaprevir for 8 weeks or sofosbuvir-velpatasvir for 12 weeks. POLARIS-2, which enrolled patients infected with all HCV genotypes with or without cirrhosis, except patients with genotype 3 and cirrhosis, was designed to test the non-inferiority of 8 weeks of sofosbuvir-velpatasvir-voxilaprevir to 12 weeks of sofosbuvir-velpatasvir using a non-inferiority margin of 5%. POLARIS-3, which enrolled patients infected with HCV genotype 3 who had cirrhosis, compared rates of SVR in both groups to a performance goal of 83%. RESULTS: In POLARIS-2, 95% (95% CI, 93%-97%) of patients had an SVR to 8 weeks of sofosbuvir-velpatasvir-voxilaprevir; this did not meet the criterion to establish non-inferiority to 12 weeks of sofosbuvir-velpatasvir, which produced an SVR in 98% of patients (95% CI, 96%-99%; difference in the stratum-adjusted Mantel-Haenszel proportions of 3.4%; 95% CI, -6.2% to -0.6%). The difference in the efficacy was primarily due to a lower rate of SVR (92%) among patients with HCV genotype 1a infection receiving 8 weeks of sofosbuvir-velpatasvir-voxilaprevir. In POLARIS-3, 96% of patients (95% CI, 91%-99%) achieved an SVR in both treatment groups, which was significantly superior to the performance goal. Overall, the most common adverse events were headache, fatigue, diarrhea, and nausea; diarrhea and nausea were reported more frequently by patients receiving voxilaprevir. In both trials, the proportions of patients who discontinued treatment owing to adverse events were low (0-1%). CONCLUSIONS: In phase 3 trials of patients with HCV infection, we did not establish that sofosbuvir-velpatasvir-voxilaprevir for 8 weeks was non-inferior to sofosbuvir-velpatasvir for 12 weeks, but the 2 regimens had similar rates of SVR in patients with HCV genotype 3 and cirrhosis. Mild gastrointestinal adverse events were associated with treatment regimens that included voxilaprevir. ClinicalTrials.gov numbers: POLARIS-2, NCT02607800 and POLARIS-3, NCT02639338.

Chronic hepatitis C virus infection is well-recognized as a common blood-borne infection with global public health impact affecting 3 to 5 million persons in the United States and more than 170 million persons worldwide. Chronic hepatitis C virus infection is associated with significant morbidity and mortality due to complications of liver cirrhosis and hepatocellular carcinoma. Current therapies with all-oral direct-acting antiviral agents are associated with high rates of sustained virologic response (SVR), generally exceeding 90%. SVR is associated with a reduced risk of liver cirrhosis, hepatic decompensation, need for liver transplantation, and both liver-related and all-cause mortality. However, a subset of patients who achieve SVR will remain at long-term risk for progression to cirrhosis, liver failure, hepatocellular carcinoma, and liver-related mortality. Limited evidence is available to guide clinicians on which post-SVR patients should be monitored vs discharged, how to monitor and with which tests, how frequently should monitoring occur, and for how long. In this clinical practice update, available evidence and expert opinion are used to generate best practice recommendations on the care of patients with chronic hepatitis C virus who have achieved SVR.

BACKGROUND & AIMS: Persons with hepatitis C virus (HCV) infection are at risk of progressive liver disease, cirrhosis, and decompensation. We analyzed the effects of the direct-acting antiviral agents elbasvir and grazoprevir in patients with HCV infection and compensated cirrhosis, combining data from 6 clinical trials. METHODS: We performed an integrated analysis of 402 patients with HCV genotype 1, 4, or 6 infection and Child-Pugh A compensated cirrhosis enrolled in 6 clinical trials. All patients received elbasvir/grazoprevir 50 mg/100 mg once daily, with or without ribavirin, for 12-18 weeks. The primary end point was sustained virologic response 12 weeks after completion of therapy (SVR12), defined as a level of HCV RNA <15 IU/mL. RESULTS: Among treatment-naive and treatment-experienced patients receiving elbasvir/grazoprevir for 12 weeks, 97.8% (135 of 138) and 88.9% (48 of 54) achieved SVR12, respectively. Among patients receiving elbasvir/grazoprevir for 12 weeks, addition of ribavirin did not increase the proportion of treatment-naive patients (90.3%, 28 of 31) or treatment-experienced patients who achieved an SVR12 (91.4%, 74 of 81). All (49 of 49) treatment-experienced patients receiving elbasvir/grazoprevir with ribavirin for 16 or 18 weeks, and 93.9% (46 of 49) of patients receiving elbasvir/grazoprevir without ribavirin for 16 or 18 weeks achieved SVR12. Virologic failure was higher among patients with HCV genotype 1a infections compared with patients with genotype 1b or 4 infections, particularly in patients who had not responded to previous interferon therapy. Baseline tests for resistance-associated substitutions (RASs) led to an individualized approach for selecting treatment duration and established a need for ribavirin for patients with HCV genotype 1a infection and RASs, regardless of treatment history. Among patients with HCV genotype 1a infection with and without baseline RASs in HCV nonstructural protein 5A who received elbasvir/grazoprevir for 12 weeks, 73% (8 of 11) and 98% (96 of 98) achieved SVR12, respectively. Both patients with HCV genotype 1a infection with baseline RASs who received 16 or 18 weeks of elbasvir/grazoprevir and ribavirin achieved SVR12. Grade 3 or 4 increases in levels of alanine aminotransferase and aspartate aminotransferase, which did not cause symptoms, were reported in 2.3% (6 of 264) of patients receiving elbasvir/grazoprevir. Serious adverse events were reported in 3% (8 of 264) patients and no patient had a decompensation-related event. CONCLUSIONS: In an analysis of data from 6 clinical trials, rates of SVR12 ranged from 89% to 100% in patients with HCV genotype 1, 4, or 6 infections and compensated cirrhosis treated with elbasvir/grazoprevir, with or without ribavirin. Addition of ribavirin to a 12-week regimen of elbasvir/grazoprevir had little effect on the proportion of treatment-naive or treatment-experienced patients who achieved an SVR12. However, virologic failure did not occur in any treatment-experienced patients when the duration of elbasvir/grazoprevir and ribavirin therapy was extended to 16 or 18 weeks. Baseline analysis of RASs (or in the absence of this test, a history of nonresponse to interferon) can be used to determine treatment duration and the need for ribavirin in patients with HCV genotype 1a infection. Clinicaltrials.gov ID: NCT02092350, NCT02105662, NCT02105467, NCT02105701, NCT01717326, and NCT02105454.

BACKGROUND & AIMS: The efficacy of NS5A inhibitors for the treatment of patients chronically infected with hepatitis C virus (HCV) can be affected by the presence of NS5A resistance-associated substitutions (RASs). We analyzed data from 35 phase I, II, and III studies in 22 countries to determine the pretreatment prevalence of various NS5A RASs, and their effect on outcomes of treatment with ledipasvir-sofosbuvir in patients with genotype 1 HCV. METHODS: NS5A gene deep sequencing analysis was performed on samples from 5397 patients in Gilead clinical trials. The effect of baseline RASs on sustained virologic response (SVR) rates was assessed in the 1765 patients treated with regimens containing ledipasvir-sofosbuvir. RESULTS: Using a 15% cut-off, pretreatment NS5A and ledipasvir-specific RASs were detected in 13% and 8% of genotype 1a patients, respectively, and in 18% and 16% of patients with genotype 1b. Among genotype 1a treatment-naive patients, SVR rates were 91% (42/46) vs. 99% (539/546) for those with and without ledipasvir-specific RASs, respectively. Among treatment-experienced genotype 1a patients, SVR rates were 76% (22/29) vs. 97% (409/420) for those with and without ledipasvir-specific RASs, respectively. Among treatment-naive genotype 1b patients, SVR rates were 99% for both those with and without ledipasvir-specific RASs (71/72 vs. 331/334), and among treatment-experienced genotype 1b patients, SVR rates were 89% (41/46) vs. 98% (267/272) for those with and without ledipasvir-specific RASs, respectively. CONCLUSIONS: Pretreatment ledipasvir-specific RASs that were present in 8-16% of patients have an impact on treatment outcome in some patient groups, particularly treatment-experienced patients with genotype 1a HCV. LAY SUMMARY: The efficacy of treatments using NS5A inhibitors for patients with chronic hepatitis C virus (HCV) infection can be affected by the presence of NS5A resistance-associated substitutions (RASs). We reviewed results from 35 clinical trials where patients with genotype 1 HCV infection received treatments that included ledipasvir-sofosbuvir to determine how prevalent NS5A RASs are in patients at baseline, and found that ledipasvir-specific RASs were present in 8-16% of patients prior to treatment and had a negative impact on treatment outcome in subset of patient groups, particularly treatment-experienced patients with genotype 1a HCV.

High rates of sustained virologic response at post-treatment week 12 (SVR12) were achieved in six phase 3 trials of ombitasvir (OBV, an NS5A inhibitor), paritaprevir (an NS3/4A protease inhibitor) co-dosed with ritonavir (PTV/r) + dasabuvir (DSV, an NS5B RNA polymerase inhibitor) (ie, 3D regimen) with or without ribavirin (RBV) in adults with chronic genotype (GT) 1 hepatitis C virus (HCV) infection. We assessed whether time to first HCV RNA value below the lower limit of quantification in patients with and without cirrhosis was associated with achievement of SVR12. Data were analysed from GT1-infected patients enrolled in six phase 3 studies of 3D +/- RBV. Patients who experienced non-virologic failure were excluded from analysis. HCV RNA was determined using the Roche COBAS TaqMan RT-PCR assay (lower limit of quantification, LLOQ =25 IU/mL). SVR12 was analysed by week of first HCV RNA suppression, defined as HCV RNA

PMID: 27935166

ISSN: 1365-2893

CID: 2569302