Antiviral therapy with nucleotide polymerase inhibitors for chronic hepatitis C

SummaryThe treatment of hepatitis C virus (HCV) has made significant advances with the development of new direct-acting antivirals. Nucleotide polymerase inhibitors are one class of these new medications that have been shown to be highly effective, safe and well tolerated as part of an antiviral regimen. Sofosbuvir has become the first drug in this class to be approved for clinical use, supported by results from extensive phase II and phase III clinical trials. This review will further discuss nucleotide polymerase inhibitors, including the data supporting their use as part of interferon-free HCV treatment regimens

American Gastroenterological Association Institute Clinical Practice Update—Expert Review: Care of Patients Who Have Achieved a Sustained Virologic Response After Antiviral Therapy for Chronic Hepatitis C Infection

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

Superiority of Interferon-Free Regimens for Chronic Hepatitis C: The Effect on Health-Related Quality of Life and Work Productivity

Antivirals d’acció directa; Fatiga; Productivitat laboralAntivirales de acción directa; Fatiga; Productividad laboralDirect-acting antivirals; Fatigue; Work productivityPatient-reported outcomes (PROs) such as quality of life and work productivity are important for measuring patient's experience. We assessed PROs during and after treatment of hepatitis C virus (HCV) patients. Data were obtained from a phase 3 open label study of sofosbuvir and ribavirin (SOF + RBV) with and without interferon (IFN). Patients completed 4 PRO assessment instruments (SF-36, Functional Assessment of Chronic Illness Therapy—Fatigue, Chronic Liver Disease Questionnaire— HCV, Work Productivity and Activity—Specific Health Problem) before, during, and after treatment. A total of 533 patients with chronic HCV were enrolled; 28.9% treatment-naïve, 23.1% cirrhotic, 219 received IFN + SOF + RBV and 314 received IFN-free SOF + RBV. At baseline, there were no differences in PROs between the IFN-free and IFN-containing treatment arms (all P > 0.05). During treatment, patients receiving IFN + SOF + RBV had a substantial impairment in their PROs (up to −24.4% by treatment week 12, up to −8.3% at week 4 post-treatment). The PRO decrements seen in the SOF + RBV arm were smaller in magnitude (up to −7.1% by treatment week 12), and all returned to baseline or improved by post-treatment week 4. By 12 weeks after treatment cessation, patients who achieved sustained viral response-12 showed some improvement of PRO scores regardless of the regimen (up to +7.1%, P < 0.0001) or previous treatment experience. In multivariate analysis, the use of IFN was independently associated with lower PROs. IFN-based regimens have a profoundly negative impact to PROs. By contrast, the impact of RBV on these PROs is relatively modest. Achieving HCV cure is associated with improvement of most of the PRO scores

Hepatitis C viral evolution in genotype 1 treatment-naïve and treatment-experienced patients receiving telaprevir-based therapy in clinical trials

Background: In patients with genotype 1 chronic hepatitis C infection, telaprevir (TVR) in combination with peginterferon and ribavirin (PR) significantly increased sustained virologic response (SVR) rates compared with PR alone. However, genotypic changes could be observed in TVR-treated patients who did not achieve an SVR. Methods: Population sequence analysis of the NS3•4A region was performed in patients who did not achieve SVR with TVR-based treatment. Results: Resistant variants were observed after treatment with a telaprevir-based regimen in 12% of treatment-naïve patients (ADVANCE; T12PR arm), 6% of prior relapsers, 24% of prior partial responders, and 51% of prior null responder patients (REALIZE, T12PR48 arms). NS3 protease variants V36M, R155K, and V36M+R155K emerged frequently in patients with genotype 1a and V36A, T54A, and A156S/T in patients with genotype 1b. Lower-level resistance to telaprevir was conferred by V36A/M, T54A/S, R155K/T, and A156S variants; and higher-level resistance to telaprevir was conferred by A156T and V36M+R155K variants. Virologic failure during telaprevir treatment was more common in patients with genotype 1a and in prior PR nonresponder patients and was associated with higher-level telaprevir-resistant variants. Relapse was usually associated with wild-type or lower-level resistant variants. After treatment, viral populations were wild-type with a median time of 10 months for genotype 1a and 3 weeks for genotype 1b patients. Conclusions: A consistent, subtype-dependent resistance profile was observed in patients who did not achieve an SVR with telaprevir-based treatment. The primary role of TVR is to inhibit wild-type virus and variants with lower-levels of resistance to telaprevir. The complementary role of PR is to clear any remaining telaprevir-resistant variants, especially higher-level telaprevir-resistant variants. Resistant variants are detectable in most patients who fail to achieve SVR, but their levels decline over time after treatment

Phase 1B, randomized, double-blind, dose-escalation trial of CPG 10101 in patients with chronic hepatitis C virus

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NS5A Resistance-Associated Substitutions in Patients with Genotype 1 Hepatitis C Virus:Prevalence and Effect on Treatment Outcome

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-naïve 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-naïve 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 Sustained Virologic Response Rates of Glecaprevir/Pibrentasvir in Patients With Dosing Interruption or Suboptimal Adherence

INTRODUCTION: Pangenotypic, all-oral direct-acting antivirals, such as glecaprevir/pibrentasvir (G/P), are recommended for treatment of hepatitis C virus (HCV) infection. Concerns exist about the impact on efficacy in patients with suboptimal adherence, particularly with shorter treatment durations. These post hoc analyses evaluated adherence (based on pill count) in patients prescribed 8- or 12-week G/P, the impact of nonadherence on sustained virologic response at post-treatment week 12 (SVR12), factors associated with nonadherence, and efficacy in patients interrupting G/P treatment. METHODS: Data were pooled from 10 phase 3 clinical trials of treatment-naive patients with HCV genotype 1-6 without cirrhosis/with compensated cirrhosis (treatment adherence analysis) and 13 phase 3 clinical trials of all patients with HCV (interruption analysis). RESULTS: Among 2,149 patients included, overall mean adherence was 99.4%. Over the treatment duration, adherence decreased (weeks 0-4: 100%; weeks 5-8: 98.3%; and weeks 9-12: 97.1%) and the percentage of patients with ≥80% or ≥90% adherence declined. SVR12 rate in the intention-to-treat (ITT) population was 97.7% (modified ITT SVR12 99.3%) and remained high in nonadherent patients in the modified ITT population (<90%: 94.4%-100%; <80%: 83.3%-100%). Psychiatric disorders were associated with <80% adherence, and shorter treatment duration was associated with ≥80% adherence. Among 2,902 patients in the interruption analysis, 33 (1.1%) had a G/P treatment interruption of ≥1 day, with an SVR12 rate of 93.9% (31/33). No virologic failures occurred. DISCUSSION: These findings support the impact of treatment duration on adherence rates and further reinforce the concept of "treatment forgiveness" with direct-acting antivirals.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Daclatasvir vs telaprevir plus peginterferon alfa/ribavirin for hepatitis C virus genotype 1

AIM: To evaluate daclatasvir vs telaprevir, each combined with peginterferon alfa-2a/ribavirin (pegIFN/RBV), in treatment-naive hepatitis C virus (HCV) genotype (GT) 1-infected patients. METHODS: In this phase 3, randomized, open-label, noninferiority study, 602 patients were randomly assigned (2:1) to daclatasvir vs telaprevir, stratified by IL28B rs12979860 host genotype (CC vs non-CC), cirrhosis status (compensated cirrhosis vs no cirrhosis), and HCV GT1 subtype (GT1a vs GT1b). Patients were selected by study inclusion criteria from a total of 793 enrolled patients. Patients received daclatasvir 60 mg once daily or telaprevir 750 mg 3 times daily plus pegIFN/RBV. Daclatasvir recipients received 24 wk of daclatasvir plus pegIFN/RBV; those without an extended rapid virologic response (eRVR; undetectable HCV-RNA at weeks 4 and 12) received an additional 24 wk of pegIFN/RBV. Telaprevir-treated patients received 12 wk of telaprevir plus pegIFN/RBV followed by 12 (with eRVR) or 36 (no eRVR) wk of pegIFN/RBV. The primary objective was to compare for noninferiority of sustained virologic response rates at posttreatment week 12 (SVR12) in GT1b-infected patients. Key secondary objectives were to demonstrate that the rates of anemia (hemoglobin < 10 g/dL) and rash-related events, through week 12, were lower with daclatasvir + pegIFN/RBV than with telaprevir + pegIFN/RBV among GT1b-infected patients. Resistance testing was performed using population-based sequencing of the NS5A region for all patients at baseline, and for patients with virologic failure or relapse and HCV-RNA ≥ 1000 IU/mL, to investigate any link between NS5A polymorphisms associated with daclatasvir resistance and virologic outcome. RESULTS: Patient demographics and disease characteristics were generally balanced across treatment arms; however, there was a higher proportion of black/African Americans in the daclatasvir groups (6.0% and 8.2% in the GT1b and GT1a groups, respectively) than in the telaprevir groups (2.2% and 3.0%). Among GT1b-infected patients, daclatasvir plus pegIFN/RBV was noninferior to telaprevir plus pegIFN/RBV for SVR12 [85% (228/268) vs 81% (109/134); difference, 4.3% (95%CI: -3.3% to 11.9%)]. Anemia (hemoglobin < 10 g/dL) was significantly less frequent with daclatasvir than with telaprevir [difference, -29.1% (95%CI: -38.8% to -19.4%)]. Rash-related events were also less common with daclatasvir than with telaprevir, but the difference was not statistically significant. In GT1a-infected patients, SVR12 was 64.9% with daclatasvir and 69.7% with telaprevir. Among both daclatasvir and telaprevir treatment groups, across GT1b- or GT1a-infected patients, lower response rates were observed in patients with IL28B non-CC and cirrhosis - factors known to affect response to pegIFN/RBV. Consistent with these observations, a multivariate logistic regression analysis in GT1b-infected patients demonstrated that SVR12 was associated with IL28B host genotype (CC vs non-CC, P = 0.011) and cirrhosis status (absent vs present, P = 0.031). NS5A polymorphisms associated with daclatasvir resistance (at L28, R30, L31, or Y93) were observed in 17.3% of GT1b-infected patients at baseline; such variants did not appear to be absolute predictors of failure since 72.1% of these patients achieved SVR12 compared with 86.9% without these polymorphisms. Among GT1b-infected patients, treatment was completed by 85.4% (229/268) in the daclatasvir group, and by 85.1% (114/134) in the telaprevir group, and among GT1a-infected patients, by 67.2% (90/134) and 69.7% (46/66), respectively. Discontinuations (of all 3 agents) due to an AE were more frequent with telaprevir than with daclatasvir, whereas discontinuations due to lack of efficacy were more frequent with daclatasvir, due, in part, to differences in futility criteria. CONCLUSION: Daclatasvir plus pegIFN/RBV demonstrated noninferiority to telaprevir plus pegIFN/RBV for SVR12 and was well-tolerated in treatment-naive GT1b-infected patients, supporting the use of daclatasvir with other direct-acting antivirals