Modeling-Based Response-Guided DAA Therapy for Chronic Hepatitis C to Identify Individuals for Shortening Treatment Duration

Shortening duration of direct-acting antiviral therapy for chronic hepatitis C could provide cost savings, reduce medication exposure, and foster adherence and treatment completion in special populations. The current analysis indicates that measuring hepatitis C virus at baseline and on days 7 and 14 of therapy can identify patients for shortening therapy duration.

Significant compartment-specific impact of different RNA extraction methods and PCR assays on the sensitivity of hepatitis E virus detection

BACKGROUND

RNA detection in plasma/stool is the gold-standard for diagnosis of hepatitis E virus (HEV) infection. The impact of viral extraction methods on HEV RNA detection is poorly investigated.

METHODS

We determined the limit of detection of the RealStar HEV RT-PCR V2.0 Kit (altona Diagnostics, RS) utilizing 3 RNA extraction methods (COBAS^® AmpliPrep Total Nucleic Acid Isolation Kit, TNAi Roche; MagNA Pure 96 DNA, Viral NA SV Kit, MgP; QIAamp Viral RNA mini Kit Qiagen; VRK) in plasma and stool. The most sensitive method was evaluated in a total of 307 longitudinal samples of patients with HEV infection (acute = 18/chronic = 36) and compared to results with the former diagnostic standard of our centre (TNAi/FastTrack Diagnostic; FTD).

RESULTS

The plasma-LOD was 49, 94 and 329 IU/mL for extraction with MgP, VRK and TNAi respectively. In stool, the LOD was 21 IU/mL, 528 IU/mL and indefinable for extraction with TNAi, VRK and MgP respectively. Utilizing longitudinal patient plasma samples, MgP/RS revealed 56 HEV RNA-positive samples in 158 negative samples as determined by TNAi/FTD. In stool, from 37 HEV negative samples (TNAi/FTD), 15 were positive with TNAi/RS. At end of treatment, 8 out of 27 chronically infected patients were RNA positive with MgP/RS, while classified negative with TNAi/FTD. A relapse occurred in 3 of these patients.

CONCLUSION

Different methods for RNA extraction and quantification have a significant, compartment-specific impact on the sensitivity of HEV detection. Knowledge about the favourable combinations of extraction and quantification has important implications for diagnosis and patients receiving antiviral therapy.

High Cure Rates for Hepatitis C Virus Genotype 6 in Advanced Liver Fibrosis With 12 Weeks Sofosbuvir and Daclatasvir: The Vietnam SEARCH Study

BACKGROUND

Genotype 6 is the most genetically diverse lineage of hepatitis C virus, and it predominates in Vietnam. It can be treated with sofosbuvir with daclatasvir (SOF/DCV), the least expensive treatment combination globally. In regional guidelines, longer treatment durations of SOF/DCV (24 weeks) are recommended for cirrhotic individuals, compared with other pangenotypic regimens (12 weeks), based on sparse data. Early on-treatment virological response may offer means of reducing length and cost of therapy in patients with liver fibrosis.

METHODS

In this prospective trial in Vietnam, genotype 6-infected adults with advanced liver fibrosis or compensated cirrhosis were treated with SOF/DCV. Day 14 viral load was used to guide duration of therapy: participants with viral load <500 IU/mL at day 14 were treated with 12 weeks of SOF/DCV and those ≥500 IU/mL received 24 weeks. Primary endpoint was sustained virological response (SVR).

RESULTS

Of 41 individuals with advanced fibrosis or compensated cirrhosis who commenced treatment, 51% had genotype 6a and 34% had 6e. The remainder had 6h, 6k, 6l, or 6o. One hundred percent had viral load <500 IU/mL by day 14, meaning that all received 12 weeks of SOF/DCV. One hundred percent achieved SVR12 despite a high frequency of putative NS5A inhibitor resistance-associated substitutions at baseline.

CONCLUSIONS

Prescribing 12 weeks of SOF/DCV results in excellent cure rates in this population. These data support the removal of costly genotyping in countries where genotype 3 prevalence is <5%, in keeping with World Health Organization guidelines. NS5A resistance-associated mutations in isolation do not affect efficacy of SOF/DCV therapy. Wider evaluation of response-guided therapy is warranted.

Modeling-Based Response-Guided Glecaprevir-Pibrentasvir Therapy for Chronic Hepatitis C to Identify Patients for Ultrashort Treatment Duration

We recently showed in a proof-of-concept study that real-time modeling-based response-guided therapy can shorten hepatitis C virus treatment duration with sofosbuvir-velpatasvir, elbasvir-grazoprevir, and sofosbuvir-ledipasvir without compromising efficacy, confirming our retrospective modeling reports in >200 patients. However, retrospective modeling of pibrentasvir-glecaprevir (P/G) treatment has yet to be evaluated. In the current study, modeling hepatitis C virus kinetics in 44 cirrhotic and noncirrhotic patients predicts that P/G treatment might have been reduced to 4, 6, and 7 weeks in 16%, 34%, and 14% of patients, respectively. These results support the further evaluation of a modeling-based response-guided therapy approach using P/G.

Standard Versus Extended Duration Direct-Acting Antiviral Therapy in Hepatitis C Patients With Slow Response to Treatment

BACKGROUND

Response-guided hepatitis C therapy was standard with interferon-based regimens but is not used for direct-acting antivirals (DAAs). Week 4 viral kinetics may predict sustained virological response (SVR) with DAAs, but it is unclear whether extending therapy in slow responders affects outcomes.

OBJECTIVES

The primary objective was to compare SVR rates between traditional and extended duration groups. Secondary objectives were to compare SVR rates among subgroups and to determine factors associated with SVR.

METHODS

This institutional review board-approved, retrospective, single-center study identified patients with chronic hepatitis C virus (HCV) infection with detectable week 4 HCV RNA who were treated with DAAs. Patients were excluded for early discontinuation, treatment regimen not recommended first-line, or missing HCV RNA labs. Patients were stratified into traditional and extended duration groups. The primary end point was SVR. Secondary end points included factors associated with SVR and rationale for extension of therapy duration.

RESULTS

A total of 363 patients were included; 58 (16%) received extended therapy. Patients were primarily genotype 1a (70%) and treatment naïve (80%). More than half had advanced fibrosis or cirrhosis. SVR12 rates were 100% in the extended duration group and 96.7% in the traditional duration group (P = 0.37). There were no associations with SVR and prespecified patient-specific factors. Sample size was limited.

CONCLUSION AND RELEVANCE

Based on these findings, a recommendation for extension of therapy cannot be made for patients with detectable HCV RNA at week 4 of treatment at this time. Cost analyses may help guide recommendations to re-treat rare failures versus extend therapy in all slow responders.

On-treatment HCV RNA as a predictor of sustained virological response in HCV genotype 3-infected patients treated with daclatasvir and sofosbuvir

BACKGROUND AND AIMS

Many currently available direct-acting antiviral (DAA) regimens are less effective against HCV genotype 3 than against other HCV genotypes. The all-oral, pangenotypic DAA combination of daclatasvir (NS5A inhibitor) + sofosbuvir (nucleotide NS5B inhibitor) was studied in genotype 3-infected treatment-naive and -experienced patients (ALLY-3) who achieved rates of sustained virological response at post-treatment Week 12 (SVR12) of 90 and 86% respectively. In this analysis, we assessed whether on-treatment responses to daclatasvir + sofosbuvir in genotype 3-infected patients could predict treatment outcome.

METHODS

In ALLY-3, treatment-naive and -experienced patients, with or without cirrhosis, were treated with daclatasvir + sofosbuvir for 12 weeks. HCV RNA kinetics and categorical virological responses on treatment were assessed. The proportions of responders and nonresponders by study week, and time to first undetectable HCV RNA, were analysed for utility in predicting treatment outcome.

RESULTS

Overall, HCV RNA levels declined rapidly during Week 1 of treatment in both treatment-naive and -experienced cohorts. Although patients with cirrhosis had a slower initial virological response as measured by the proportion of patients with HCV RNA below the lower limit of quantification at Week 1, responses converged thereafter. Positive and negative predictive values calculated for on-treatment responses were generally comparable with the overall SVR12 rate and were therefore limited indicators of outcome. SVR12 rates were not impacted by time to first undetectable HCV RNA.

CONCLUSIONS

On-treatment responses are not useful predictors of ultimate virological response to the daclatasvir + sofosbuvir regimen.

Multicenter prospective study to optimize the efficacy of triple therapy with telaprevir in patients with genotype 1b hepatitis C virus infection according to an algorithm based on the drug Adherence, IL-28B Gene Allele and Viral Response Trial (AG & RGT)

AIM

To optimize the therapeutic efficacy of NS3/4A protease inhibitors, a multicenter prospective study was performed according to an algorithm based on the Adherence, IL-28B Gene Allele and Viral Response Trial (AG & RGT).

METHODS

A total of 340 patients with genotype 1b hepatitis C virus (HCV) showing serum RNA levels of >5 log were enrolled. The duration of ribavirin/pegylated interferon (PEG IFN)-α-2b therapy was prolonged to 48 weeks in patients with unfavorable IL28B alleles showing adherence rates of less than 80% for either drug during the first 12 weeks even if RVR had been achieved, and in those in whom cEVR, but not RVR, was achieved; furthermore, to 72 weeks in those showing partial early viral response.

RESULTS

The therapeutic outcomes were assessed in 282 patients, and the therapy was set to complete at 24 weeks in 181 patients (64%) and to prolong to 48 weeks or 72 weeks in 71 patients (25%). The former group showed a SVR rate of 84%, while the latter group showed an SVR rate of 69% with a relapse rate of 7%. The SVR rate was 33% in the 30 patients (11%) in whom the therapy had to be discontinued in less than 12 weeks. Thus, the results of intention-to-treat analysis revealed an overall SVR rate of 75%. Multivariate analysis identified prolongation of the duration of therapy as a significant factor associated with SVR.

CONCLUSION

Triple therapy yielded a high SVR rate in the AG & RGT trial via attenuation of viral relapse by prolonged ribavirin/PEG IFN-α-2b administration. © 2015 The Japan Society of Hepatology.

Is response-guided therapy being applied in the clinical setting? The hepatitis C example

BACKGROUND

Response-guided therapy (RGT) is a treatment model that bases adjustments to therapeutic regimens on individualized patient physiologic response. This approach is applied to patients with chronic hepatitis C virus (HCV) infection who are treated with a triple therapy regimen of boceprevir or telaprevir in combination with pegylated interferon and ribavirin. As RGT expands in other pharmacologic regimens, including the treatment of breast cancer and acute myeloid leukemia, a measurement of how this approach is applied in clinical practice is important to determine whether the benefits of RGT are being optimized.

OBJECTIVE

To measure adherence to the RGT guidelines and to the treatment futility rules based on the drug labeling information for boceprevir and for telaprevir in the treatment of patients with chronic HCV infection.

METHODS

A retrospective observational cohort study was conducted using the large Humana research database, which includes pharmacy, medical, and laboratory claims, as well as enrollment data for more than 1.5 million fully insured commercial members, 1.9 million Medicare Advantage members, and 2.4 million Medicare Part D members from all 50 states. The study population included patients aged ≥18 years to <90 years who were fully insured with commercial or Medicare Advantage coverage. A pharmacy claim for boceprevir or telaprevir was used to identify patients receiving triple therapy for HCV infection. Medical, pharmacy, and laboratory claims were reviewed from the date of the first boceprevir or telaprevir pharmacy claim between May 2011 and February 2012 through a 32-week follow-up period, during which patients were required to have continuous health plan enrollment eligibility. This time period allowed for the occurrences of required HCV RNA laboratory monitoring and the assessment of treatment patterns. The use of RGT for boceprevir and telaprevir includes the monitoring of HCV RNA levels at routine intervals to determine how to proceed with therapy. Adherence to HCV RNA monitoring was measured as the proportion of eligible patients who had an HCV RNA assay at each of the recommended time intervals. According to futility rules, patients with greater-than-expected HCV RNA levels are deemed to be nonresponders and should discontinue therapy. Adherence to futility rules was measured as the proportion of patients who stopped therapy among all patients who had an HCV RNA result, which indicated treatment futility at each monitoring interval.

RESULTS

A total of 326 patients (65 in the boceprevir group; 261 in the telaprevir group) were eligible for the HCV RNA monitoring analysis, and 134 patients (20 receiving boceprevir and 114 receiving telaprevir) were eligible for the futility rules analysis. There were 1203 HCV RNA assays during the follow-up period. The percentage of patients who were adherent to HCV RNA monitoring during the entire treatment period was 29.2% in the boceprevir group and 32.2% in the telaprevir group. In both treatment groups, adherence to HCV RNA monitoring was highest at the first recommended time interval, followed by a downward trend in the second and third time intervals. Approximately 15% of 134 eligible patients met the futility rules for stopping therapy based on HCV RNA assay results, and 55% of those patients stopped the therapy in accordance with the treatment futility rules.

CONCLUSION

The implementation of RGT was suboptimal in this population of patients with chronic HCV infection; adherence to HCV RNA monitoring guidelines was less than 33%, and adherence to treatment futility rules was less than 50%. Managed care pharmacists should identify strategies to increase the adoption of RGT, which may, in turn, improve patient care and reduce unnecessary expenditures.

How to optimize current therapy in hepatitis C virus genotype 1 patients. Predictors of response to interferon-based therapy with second wave direct acting antivirals

Second wave direct acting antivirals such as sofosbuvir, simeprevir and daclatasvir can be combined with pegylated interferon alpha and ribavirin (PEG-IFN/RBV) as triple therapy in patients with hepatitis C virus (HCV) infection. In patients with HCV genotype 1 (HCV-1), a PEG-IFN/RBV-based regimen with sofosbuvir is highly effective but the presence of cirrhosis and the non-CC IFNL3 genotype have been associated with a poorer response. A PEG-IFN/RBV-based regimen with simeprevir or daclatasvir is based on response-guided therapy and its efficacy depends on predictors of response to IFN. HCV-1 subtype is also a major predictor of response. In HCV-1a infected patients, the K80Q mutation in NS3 or the presence of NS5A variants at baseline are associated with poor response with simeprevir- or daclatasvir-containing regimens respectively. Thus, these regimens should be only used in HCV-1b patients with good predictors of response to IFN.

DAUPHINE: a randomized phase II study of danoprevir/ritonavir plus peginterferon alpha-2a/ribavirin in HCV genotypes 1 or 4

BACKGROUND & AIMS

Danoprevir is a hepatitis C virus (HCV) protease inhibitor with activity against genotypes (G)1/G4, which is maintained at lower doses by ritonavir-boosting. We report results of a large, randomized, active-controlled phase IIb study of ritonavir-boosted danoprevir (danoprevir/r) plus peginterferon alpha-2a/ribavirin (P/R) in treatment-naive patients with HCV G1/4 infection.

METHODS

Treatment-naive patients with HCV G1/4 infection were randomized to twice-daily danoprevir/r 200/100 mg (A, n = 92); 100/100 mg (B, n = 93); or 50/100 mg (C, n = 94) plus P/R for 24 weeks; twice-daily danoprevir/r 100/100 mg (D, n = 94) plus P/R for 12 or 24 weeks; or P/R alone (E, n = 44) for 48 weeks. Patients in the response-guided therapy arm (D) with an extended rapid virological response (eRVR2: HCV RNA <15 IU/ml during Weeks 2-10) stopped all therapy at Week 12; non-eRVR2 patients continued all treatment to Week 24. The primary efficacy endpoint was sustained the virological response (SVR24: HCV RNA <15 IU/ml after 24 weeks of untreated follow-up).

RESULTS

SVR24 rates in Arms A, B, C, D and E were 89.1%, 78.5%, 66.0%, 69.1% and 36.4%, respectively, in the overall population; 83.6%, 69.6%, 60.3%, 59.2% and 38.5% in G1a-infected patients, 96.6%, 93.1%, 73.1%, 78.4% and 28.6% in G1b-infected patients and 100%, 87.5%, 100%, 100% and 66.7% in G4-infected patients. Danoprevir/r plus P/R was generally well tolerated compared with P/R alone. There was a higher incidence of serious adverse events in danoprevir-treatment arms, but most were associated with P/R.

CONCLUSIONS

The combination of danoprevir/r plus P/R is efficacious in treatment-naïve patients with HCV genotype 1 or 4 infection.

Pretreatment prediction of the outcome of response-guided peginterferon-α and ribavirin therapy for chronic hepatitis C

BACKGROUND AND AIM

The accuracy for predicting virological outcomes of peginterferon-α and ribavirin therapy in patients with chronic hepatitis C is limited to approximately 80%, even with IL28B genotyping. Our in vitro study revealed that the numbers of (TA) dinucleotide repeats [(TA)n] of rs72258881, which is located in the promoter region of IL28B gene, might regulate IL28B transcription. We aimed to evaluate the usefulness of these host factors for predicting virological outcomes of this therapy in response-guided clinical settings.

METHODS

A nationwide, multi-center prospective study in Japan determined IL28B (rs8099917) genotype, (TA)n of rs72258881, and amino acid substitutions of hepatitis C virus and used these for multivariate analysis together with other parameters at pretreatment.

RESULTS

After enrolling 215 patients with genotype 1 and high viral load from 23 hospitals between October 2009 and February 2011, intent-to-treat analysis identified 202 patients in whom the final virological outcomes could be determined. Non-virological response by non-TT genotype was predicted with 79.7% accuracy. When combined with the (TA)n, the incidences of virological response tended to be higher in the longer (TA)n group, regardless of rs8099917 genotype. Multivariate logistic regression analysis revealed that rs8099917 non-TT genotype (P < 0.001), shorter (TA)n (P = 0.011), mutation of amino acid 70 in the virus core region (P = 0.029), and lower levels of serum albumin (P = 0.036) were independently associated with non-virological response.

CONCLUSIONS

IL28B genotype and (TA)n of rs72258881 may independently affect virological outcomes of peginterferon-α and ribavirin as host factors, even in response-guided therapy.

The role of interferon in the new era of hepatitis C treatments

Interferon has been the backbone of HCV treatment since this agent was first introduced nearly two decades ago. Interferon acts to eradicate HCV via two mechanisms: by directly inhibiting HCV replication via an indirect anti-viral mechanism and by modulating an immune response against hepatocytes infected with HCV. The current treatment of chronic HCV genotype 1 is the combination of peginterferon, ribavirin and a single direct acting anti-viral agent (DAA). Within the next 1-2 years multiple DAA combinations will eradicate and cure HCV at high rates without interferon. The role interferon will play in the next era of HCV treatment will depend upon balancing cost, efficacy and the development of an interferon with a more favorable adverse event profile.

Response-guided therapy in patients with genotype 1 hepatitis C virus: current status and future prospects

On-treatment responses to antiviral therapy are used to determine duration of therapy in patients being treated for genotype 1 hepatitis C virus infection. Such use of response-guided therapy has successfully reduced exposure of patients to the side-effects of pegylated interferon and ribavirin without jeopardizing overall treatment success. Response-guided therapy is an integral part of treatment using the current standard treatments involving the direct-acting antiviral (DAA) agents--boceprevir or telaprevir--combined with pegylated interferon/ribavirin. Improvements in our understanding of the kinetics of viral load during antiviral therapy have shown us that more potent suppression of viral replication increases the rate of viral eradication, providing impetus for the development of more potent DAAs. Emerging results from clinical trials of these agents--including trials of interferon-free DAA combinations--suggest that very high rates of viral eradication are achievable, even in patients who failed to respond to previous courses of interferon-based therapy. Furthermore, because of these high rates of treatment success, on-treatment assessment of viral response may become unnecessary. The field of hepatitis C virus therapy is evolving rapidly and current trends indicate that the era of simple treatment regimens with high rates of success and good tolerability are near.

Relevance of the Core 70 and IL-28B polymorphism and response-guided therapy of peginterferon alfa-2a ± ribavirin for chronic hepatitis C of Genotype 1b: a multicenter randomized trial, ReGIT-J study

BACKGROUND

We conducted a multicenter randomized clinical trial to determine the optimal treatment strategy against chronic hepatitis C virus (HCV) with genotype 1b and a high viral load (G1b/high).

METHODS

The study subjects included 153 patients with G1b/high. Patients were initially treated with PEG-IFNα-2a alone and then randomly assigned to receive different treatment regimens. Ribavirin (RBV) was administered to all patients with HCV RNA at week 4. Patients negative for HCV RNA at week 4 were randomly assigned to receive PEG-IFNα-2a (group A) or PEG-IFNα-2a/RBV (group B). Patients who showed HCV RNA at week 4 but were negative at week 12 were randomly assigned to receive weekly PEG-IFNα-2a (group C) or biweekly therapy (group D). Patients who showed HCV RNA at week 12 but were negative at week 24 were randomly assigned to receive PEG-IFNα-2a/RBV (group E) or PEG-IFNα-2a/RBV/fluvastatin (group F).

RESULTS

Overall, the rate of sustained virological response (SVR) was 46 % (70/153). The total SVR rate in the group (A, D, and F) of response-guided therapy was significantly higher than that in the group (B, C, and E) of conventional therapy [70 % (38/54) versus 52 % (32/61), p = 0.049]. Although IL28-B polymorphism and Core 70 mutation were significantly associated with efficacy, patients with rapid virological response (RVR) and complete early virological response (cEVR) achieved high SVR rates regardless of their status of IL-28B polymorphism and Core 70 mutation.

CONCLUSION

In addition to knowing the IL-28B polymorphism and Core 70 mutation status, understanding the likelihood of virological response during treatment is critical in determining the appropriate treatment strategy.

Expert recommendations on the application of interferon for chronic hepatitis B

To help the clinicians correctly and scientifically apply interferon for the treatment of chronic hepatitis B, more than 40 experts majored in infectious and liver diseases updated the 'Expert recommendations on the treatment of chronic hepatitis B with interferon (2007)' following a systematic literature review, summary of clinical experiences and thorough consultation and discussion. The updated expert recommendations primarily included fundamental new knowledge of the use of interferon and individualized interferon therapy. Specifically, we provided recommendations for implementing optimized therapeutic regimens based on quantitative changes in hepatitis B surface antigen and hepatitis B virus DNA levels 24 weeks after interferon therapy. The updated expert recommendations provided itemized details and supplement for the Guidelines for the Prevention and Treatment of Chronic Hepatitis B and they also offer a basis for individualized therapy of chronic hepatitis B with interferon.

New proposal for response-guided peg-interferon-plus-ribavirin combination therapy for chronic hepatitis C virus genotype 2 infection

This study aimed to determine the most suitable duration of pegylated-interferon (Peg-IFN)-plus-ribavirin combination therapy in patients infected with hepatitis C virus (HCV) genotype 2 who had not achieved rapid virological response (serum HCV RNA disappearance after 4 weeks of therapy). HCV genotype 2 patients (n = 182) with a high viral load received >80% of the standard Peg-IFN-plus-ribavirin dose for at least 24 weeks, and their final virological responses were studied. Patients were classified into "rapid virological response" and "non-rapid virological response" groups. The non-rapid virological response group was further divided into a "virological response at 8 weeks" (serum HCV RNA disappearance after 8 weeks of therapy) and a "non-virological response at 8 weeks" group. Factors related to rapid virological response and optimal therapy duration in the non-rapid virological response group were evaluated. Multivariate logistic regression analysis showed that subtype HCV genotype 2a (P = 0.0015) and low concentration of pretreatment serum HCV RNA (P = 0.0058) were independent factors in a rapid virological response. In the virological response at 8 weeks group, the sustained virological response rate after 24 weeks of therapy was significantly lower than after 36 weeks (P = 0.044) or after 48 weeks (P = 0.006), and was similar for 36- and 48-weeks. The cost for achieving (CAS) one sustained virological response was lowest with 36-week therapy. Prolongation of Peg-IFN-plus-ribavirin combination therapy to 36 weeks is suitable for achieving virological response at 8 weeks, given the high, sustained virological response rate and cost benefit.