Review article: adherence to medication for chronic hepatitis C - building on the model of human immunodeficiency virus antiretroviral adherence research

Patients with severe mental illness and hepatitis C virus infection benefit from new pangenotypic direct-acting antivirals: Results of a literature review

INTRODUCTION

Hepatitis C virus (HCV) infection is a global health problem that can results in cirrhosis, hepatocellular carcinoma and even death. HCV infection is 3-20-fold more prevalent among patients with versus without severe mental illness (SMI), such as major depressive disorder, personality disorder, bipolar disorder and schizophrenia. Treatment options for HCV were formerly based on pegylated interferon alpha, which is associated with neuropsychiatric adverse events, and this contributed to the exclusion of patients with SMI from HCV treatment, elimination programmes, and clinical trials. Moreover, the assumption of poor adherence, scant access to healthcare and the stigma and vulnerability of this population emerged as barriers and contributed to the low rates of treatment and efficacy.

METHODS

This paper reviews the literature published between December 2010 and December 2020 exploring the epidemiology of HCV in patients with SMI, and vice versa, the effect of HCV infection, barriers to the management of illness in these patients, and benefits of new therapeutic options with pangenotypic direct antiviral agents (DAAs).

RESULTS

The approval of DAAs has changed the paradigm of HCV infection treatment. DAAs have proven to be an equally efficacious and safe option that improves quality of life (QoL) in patients SMI.

CONCLUSIONS

Knowledge of the consequences of the HCV infection and the benefits of treatment with new pangenotypic DAAs among psychiatrists can increase screening, referral and treatment of HCV infection in patients with SMI.

Nonadherence to Ledipasvir/Sofosbuvir Did Not Predict Sustained Virologic Response in a Randomized Controlled Trial of Human Immunodeficiency Virus/Hepatitis C Virus Coinfected Persons Who Use Drugs

BACKGROUND

Eliminating hepatitis C virus (HCV) will require effective treatment delivery to persons with substance use disorders (SUDs). We evaluated the relationship between ledipasvir/sofosbuvir treatment persistence (receiving 84 tablets), adherence, and sustained virologic response (SVR) in persons with human immunodeficiency virus (HIV)/HCV coinfection.

METHODS

Of the 144 participants with HIV/HCV and SUDs, 110 initiated a 12-week treatment course under 1 of 3 conditions (usual care, peer mentors, and cash incentives). We used self-report, pharmacy pill counts, and expected date of refill to examine adherence. Persistent participants were categorized as high adherence (taking ≥90% of doses) or low adherence (taking <90% of doses).

RESULTS

Most participants persisted on treatment after initiation (n = 105), with 95% (n = 100) achieving SVR. One third (34%) of participants had moderate/heavy alcohol use by the biomarker phosphatidylethanol ([Peth] ≥50 ng/mL), and 44% had urine toxicology positive for cocaine or heroin at enrollment. The proportion of persons with high adherence was 72% (n = 76), and the proportion of persons with low adherence was 28%. Although low adherence was associated with moderate/heavy alcohol use by PEth (relative risk = 2.77; 95% confidence interval, 1.50-5.12), SVR did not vary according to adherence (P = .702), and most participants (97%) with low adherence achieved SVR.

CONCLUSIONS

Treatment persistence led to high SVR rates among persons with HIV/HCV, despite imperfect adherence and SUDs.

Pretreatment Assessment of Psychosocial Readiness Is Not Associated with Improved Treatment Outcomes in a Safety-Net HCV Treatment Clinic

OBJECTIVES

Hepatitis C virus (HCV) is highly curable with antiviral therapy, and traditionally, treatment adherence has been critical for treatment success. We sought to determine whether assessing HCV treatment readiness with a structured treatment readiness tool was associated with increased rates of adherence and cure among patients at a safety-net HCV clinic.

METHODS

We administered the Psychosocial Readiness Evaluation and Preparation for HCV Treatment (PREP-C) tool to 50 patients and compared them with 50 patients who received the usual care. The outcome measures included achievement of treatment milestones (eg, adherence to treatment, clinic visit attendance) and sustained virologic response (cure).

RESULTS

We found no association between receiving the PREP-C assessment and outcomes, including referral to or starting HCV treatment, adherence to treatment, and HCV cure.

CONCLUSIONS

We found that receiving the PREP-C assessment did not improve treatment outcomes, suggesting that targeted pretreatment assessment is unnecessary even in a medically and psychosocially complex population.

Wirelessly Observed Therapy to Optimize Adherence and Target Interventions for Oral Hepatitis C Treatment: Observational Pilot Study

BACKGROUND

A fixed-dose combination of ledipasvir/sofosbuvir (LDV/SOF) is efficacious in treating chronic hepatitis C virus (HCV) infection; however, objective adherence to prescribed regimens in real-world clinical settings has not been well studied.

OBJECTIVE

This study aimed to evaluate adherence and virologic outcomes in patients with chronic HCV infection treated with LDV/SOF using a novel digital medicine program that directly measures drug ingestion adherence.

METHODS

This prospective, observational, open-label, single-arm pilot study was conducted at 2 clinical research sites and followed patients with HCV infection who were prescribed LDV/SOF along with an ingestible sensor. Patients were treated for 8 or 12 weeks. The main outcomes were ingestion adherence, medical interventions, virologic response, safety, and patient satisfaction.

RESULTS

Of the 28 patients (mean 59 years, SD 7), 61% (17/28) were male, 61% (17/28) were non-Caucasian, and 93% (26/28) were treatment naïve. All 28 had genotype 1 HCV, and of these, 27 completed an 8- or 12-week treatment. Patients used the digital medicine program for 92% of the expected days; the overall mean ingestion adherence rate was 97%. Providers used the digital medicine program data for same-day medication therapy management in 39% (11/28) of patients. End-of-treatment response was achieved in all the available 21 of 28 patients. Sustained virologic response at 12 weeks or more was achieved in 26 of 28 patients; of the 2 patients who relapsed, one had less than 90% adherence and the other had greater than or equal to 95% adherence, lending insights into reasons for treatment failure. A total of 4 subjects reported nonserious adverse events, which were resolved.

CONCLUSIONS

Conclusions: The findings of this study suggest that digital medicines can be used for wirelessly observed therapy to support adherence to antiviral HCV therapy, reduce unnecessary medication wastage and retreatment costs, and potentially optimize sustained virologic response rates, especially in populations at high risk for nonadherence.

Measuring Adherence to Hepatitis C Direct-Acting Antiviral Medications: Using the VAS in an HCV Treatment Clinic

OBJECTIVES

To implement the widespread treatment of hepatitis C virus (HCV), validated self-report measures to assess medication adherence are needed for monitoring patients who are prescribed HCV direct-acting antivirals (DAAs). The Visual Analog Scale (VAS) is an efficient and well-validated tool for measuring adherence to antiretrovirals in human immunodeficiency virus populations. This study compared VAS scores with pill counts and serum levels of HCV RNA in a sample of HCV-infected veterans prescribed DAAs.

METHODS

Veterans initiating HCV DAAs were offered enrollment in our study. HCV treatment was prescribed in accordance with the standard of care. Follow-up study visits were scheduled every 28 days for a total of 12 weeks. Adherence to DAAs was assessed at weeks 4, 8, and 12 using pill counts and the VAS score. Serum levels of HCV RNA were measured at baseline, week 4 of DAA therapy, and week 12 (Ampliprep/Taqman, lower limit of quantification 43 IU/mL).

RESULTS

Between May 2013 and December 2014, 30 veterans were enrolled. Mean adherence via pill count at weeks 4, 8, and 12 (96.2%, 95.2%, and 98.2%, respectively) was nearly identical to the mean VAS scores (96.2%, 96.0%, and 98.2%, respectively). Wilcoxon signed rank tests demonstrated no differences between each VAS and pill count pair. The VAS score inversely correlated with HCV viral load 4 weeks after DAA initiation (r -0.98) and at 12 weeks of treatment (r -0.97).

CONCLUSIONS

The VAS score compared favorably with objective measures of adherence. If future studies confirm our results, then the VAS will provide a simple and reliable method of assessing adherence to HCV DAAs in real-world treatment clinics.

Psychosocial and Neurocognitive Factors Associated With Hepatitis C - Implications for Future Health and Wellbeing

Background: Hepatitis C virus (HCV) infection involves changes not only from the point of view of physical health, but also emotional, and social that have a significant impact on the quality of life of these patients. According to the literature review, it seems that there is an important association between psychosocial factors, in particular on a cognitive level and disease progression. The aim of this mini-review is to summarize recent literature looking at the associations between psychosocial and neurocognitive factors and HCV. Methods: PubMed/Medline was systematically searched for psychosocial and neurocognitive factors associated with hepatitis C, treatment adherence, and patient wellbeing. Results: Patients present with a range of extrahepatic symptoms including fatigue, anxiety, depression, and neurocognitive dysfunction. HCV's impact on quality of life and wellbeing has serious clinical and social implications. Conclusion: Hepatitis C and its management continue to have a profound impact on health and psychologic wellbeing. Considering the serious extrahepatic implications for individuals, it is imperative that healthcare professionals pay close attention to psychosocial and neurocognitive factors. The focus on combined clinical approaches could enhance understanding about the health and social impacts of hepatitis C along the life course.

Adherence to response-guided pegylated interferon and ribavirin for people who inject drugs with hepatitis C virus genotype 2/3 infection: the ACTIVATE study

BACKGROUND

The aims of this analysis were to investigate treatment completion and adherence among people with ongoing injecting drug use or receiving opioid substitution therapy (OST) in a study of response-guided therapy for chronic HCV genotypes 2/3 infection.

METHODS

ACTIVATE was a multicenter clinical trial recruited between 2012 and 2014. Participants with genotypes 2/3 were treated with directly observed peg-interferon alfa-2b (PEG-IFN) and self-administered ribavirin for 12 (undetectable HCV RNA at week 4) or 24 weeks (detectable HCV RNA at week 4). Outcomes included treatment completion, PEG-IFN adherence, ribavirin adherence, and sustained virological response (SVR, undetectable HCV RNA >12 weeks post-treatment).

RESULTS

Among 93 people treated, 59% had recently injected drugs (past month), 77% were receiving OST and 56% injected drugs during therapy. Overall, 76% completed treatment. Mean on-treatment adherence to PEG-IFN and ribavirin were 98.2% and 94.6%. Overall, 6% of participants missed >1 dose of PEG-IFN and 31% took <95% of their prescribed ribavirin., Higher treatment completion was observed among those receiving 12 vs. 24 weeks of treatment (97% vs. 46%, P < 0.001) while the proportion of participants with 95% on-treatment ribavirin adherence was similar between groups (67% vs. 72%, P = 0.664). Receiving 12 weeks of therapy was independently associated with treatment completion. No factors were associated with 95% RBV adherence. Neither recent injecting drug use at baseline nor during therapy was associated with treatment completion or adherence to ribavirin. In adjusted analysis, treatment completion was associated with SVR (aOR 23.9, 95% CI 2.9-193.8).

CONCLUSIONS

This study demonstrated a high adherence to directly observed PEG-IFN and self-administered ribavirin among people with ongoing injecting drug use or receiving OST. These data also suggest that shortening therapy from 24 to 12 weeks can lead to improved treatment completion. Treatment completion was associated with improved response to therapy. ACTIVATE trial registration number: NCT01364090 - May 31, 2011.

Greater decline in memory and global neurocognitive function in HIV/hepatitis C co-infected than in hepatitis C mono-infected patients treated with pegylated interferon and ribavirin

The human immunodeficiency virus (HIV), hepatitis C virus (HCV), and the treatment of HCV with pegylated interferon and ribavirin (IFN/RBV) have been associated with neurocognitive and psychiatric abnormalities. The goal of this research was to prospectively evaluate neurocognitive functioning among a group of HCV mono-infected and HIV/HCV co-infected patients during the first 24 weeks of IFN/RBV treatment while accounting for practice effects, normal variations in change over time, and variations in IFN/RBV treatment exposure. Forty-four HCV mono-infected and 30 HIV/HCV co-infected patients were enrolled in a prospective study of patients beginning on IFN/RBV for chronic HCV infection. Patients were administered a depression inventory, a measure of fatigue, a structured psychiatric interview, and a neurocognitive battery at baseline and 24 weeks after initiation of treatment. Analyses were conducted to explore possible associations between neurocognitive functioning and the following: HIV/HCV co-infection vs. HCV mono-infection, IFN and RBV treatment exposure, psychiatric status, liver disease stage, and other medical characteristics. At baseline, there were no significant differences between the two groups' neuropsychiatric or neurocognitive function other than the mono-infected group had significantly higher reports of fatigue (p = 0.033). Over the course of 24 weeks of treatment after controlling for practice effects, the HIV/HCV co-infected patients experienced significantly greater declines in memory (t(56) = 2.14, p = 0.037) and global neurocognitive functioning (t(53) = 2.28, p = 0.027). In a well-characterized sample of mono-infected and co-infected patients, it appears that persons with HIV/HCV co-infection are potentially more vulnerable to neurocognitive sequalae during HCV treatment.

Social Support and Adherence for Military Veterans With Hepatitis C

PURPOSE/OBJECTIVES

The aim of this study was to describe military veterans' experiences of support and how those experiences influence their decisions to be adherent, during hepatitis C virus (HCV) treatment.

DESIGN

A qualitative phenomenological design was used. Inclusion criteria were veterans 18 years or older, receiving standard treatment for HCV, able to read, write, and communicate in English.

SETTING

A US Veterans Administration facility in Texas.

SAMPLE

Convenience sampling was used to obtain a final sample of 21 veterans.

METHODS

Data collection consisted of 1-time, in-depth interviews with analysis occurring simultaneously. Follow-up phone calls with participants verified that the themes were accurate reflections of their lived experience.

RESULTS

Because of the fear of stigma, veterans make choices about to whom they tell their diagnosis. This limits the circle of friends and coworkers who could provide support. For some veterans, family members provide emotional and practical support, but family can also be a burden. In order to cope with family and treatment demands, some veterans hibernate, whereas others socialize with friends and coworkers. Some veterans found providers to be supportive, but others did not.

CONCLUSIONS

Veterans experience both supportive and unsupportive reactions from family, friends, and healthcare providers while receiving HCV treatment. Those reactions either support or frustrate efforts to be adherent to treatment.

IMPLICATIONS

In order to support treatment adherence, healthcare providers need to assess sources of support, or burden, experienced by military veterans during HCV treatment. When veterans do not have a supportive network, they need to be encouraged to attend a support group or seek counseling. Support services need to be funded by the Veterans Administration. Providers need to practice empathy and caring in order to support adherence during treatment. Further research is needed on how military veterans manage their health after hepatitis C treatment, contrasting successful versus unsuccessful treatment outcomes.

Genotype 1 hepatitis C virus and the pharmacist's role in treatment

PURPOSE

The treatment of hepatitis C virus (HCV) genotype 1 has changed rapidly with recently approved direct-acting antiviral (DAA) regimens. The role of the pharmacist in the management of HCV therapy has increased.

SUMMARY

Chronic HCV infection is the main cause of end-stage liver disease and the primary reason for liver transplantation, liver-related death, and hepatocellular carcinoma in the United States. The recent approval of several DAAs has led to improved tolerability, sustained virological response (SVR) rates, and shorter treatment durations compared with treatment with pegylated interferon and ribavirin. Most HCV cases can be treated with the currently available regimens, and expected SVR rates exceed 90%. Several fixed-dose and pangenotypic antiviral regimens are currently in various phases of clinical trials. Pharmacists are well equipped to assist the medical team and patients with comprehensive management of HCV treatment. Pharmacists in various settings can play an instrumental role in access to HCV medications, selection of HCV treatment, detection of drug-drug interactions, and education of patients about potential adverse effects and the importance of adherence and laboratory test monitoring during HCV treatment. However, the high cost of HCV treatment poses challenges for ubiquitous treatment.

CONCLUSION

Available DAA regimens have improved HCV treatment outcomes and are selected based on efficacy, potential drug interactions, and the patient's ability to obtain medication coverage. Each of these factors provides an opportunity for pharmacist involvement in HCV management.

The Australasian Hepatology Association consensus guidelines for the provision of adherence support to patients with hepatitis C on direct acting antivirals

BACKGROUND

Hepatitis C is a blood-borne virus primarily spread through sharing of drug-injecting equipment. Approximately 150 million people worldwide and 230,000 Australians are living with chronic hepatitis C infection. In March 2016, the Australian government began subsidizing direct acting antivirals (DAAs) for the treatment of hepatitis C, which are highly effective (95% cure rate) and have few side effects. However, there is limited evidence to inform the provision of adherence support to people with hepatitis C on DAAs including the level of medication adherence required to achieve a cure.

METHODOLOGY

In February 2016, a steering committee comprising four authors convened an expert panel consisting of six hepatology nurses, a hepatologist, a pharmacist, a consumer with hepatitis C and treatment experience, and a consumer advocate. The expert panel focused on the following criteria: barriers and enablers to DAA adherence; assessment and monitoring of DAA adherence; components of a patient-centered approach to DAA adherence; patients that may require additional adherence support; and interventions to support DAA adherence. The resultant guidelines underwent three rounds of consultation with the expert panel, Australasian Hepatology Association (AHA) members (n=12), and key stakeholders (n=7) in June 2016. Feedback was considered by the steering committee and incorporated if consensus was achieved.

RESULTS

Twenty-four guidelines emerged from the evidence synthesis and expert panel discussion. The guidelines focus on the pretreatment assessment and education, assessment of treatment readiness, and monitoring of medication adherence. The guidelines are embedded in a patient-centered approach which highlights that all patients are at risk of nonadherence. The guidelines recommend implementing interventions focused on identifying patients' memory triggers and hooks; use of nonconfrontational and nonjudgmental language by health professionals; and objectively monitoring adherence.

CONCLUSION

These are the first guidelines to support patients and health professionals in the delivery of clinical care by identifying practical adherence support interventions for patients taking DAAs.

Recommendations for the management of hepatitis C virus infection among people who inject drugs

In high income countries, the majority of new and existing hepatitis C virus (HCV) infections occur among people who inject drugs (PWID). In many low and middle income countries large HCV epidemics have also emerged among PWID populations. The burden of HCV-related liver disease among PWID is increasing, but treatment uptake remains extremely low. There are a number of barriers to care which should be considered and systematically addressed, but should not exclude PWID from HCV treatment. The rapid development of interferon-free direct-acting antiviral (DAA) therapy for HCV infection has brought considerable optimism to the HCV sector, with the realistic hope that therapeutic intervention will soon provide near optimal efficacy with well-tolerated, short duration, all oral regimens. Further, it has been clearly demonstrated that HCV treatment is safe and effective across a broad range of multidisciplinary healthcare settings. Given the burden of HCV-related disease among PWID, strategies to enhance HCV assessment and treatment in this group are urgently needed. These recommendations demonstrate that treatment among PWID is feasible and provide a framework for HCV assessment and care. Further research is needed to evaluate strategies to enhance testing, linkage to care, treatment, adherence, viral cure, and prevent HCV reinfection among PWID, particularly as new interferon-free DAA treatments for HCV infection become available.

Correlates of Initiation of Treatment for Chronic Hepatitis C Infection in United States Veterans, 2004-2009

We describe the rates and predictors of initiation of treatment for chronic hepatitis C (HCV) infection in a large cohort of HCV positive Veterans seen in U.S. Department of Veterans Affairs (VA) facilities between January 1, 2004 and December 31, 2009. In addition, we identify the relationship between homelessness among these Veterans and treatment initiation. Univariate and multivariable Cox Proportional Hazards regression models with time-varying covariates were used to identify predictors of initiation of treatment with pegylated interferon alpha plus ribavirin. Of the 101,444 HCV treatment-naïve Veterans during the study period, rates of initiation of treatment among homeless and non-homeless Veterans with HCV were low and clinically similar (6.2% vs. 7.4%, p<0.0001). For all U.S. Veterans, being diagnosed with genotype 2 or 3, black or other/unknown race, having Medicare or other insurance increased the risk of treatment. Veterans with age ≥50 years, drug abuse, diabetes, and hemoglobin < 10 g/dL showed lower rates of treatment. Initiation of treatment for HCV in homeless Veterans is low; similar factors predicted initiation of treatment. Additionally, exposure to treatment with medications for diabetes predicted lower rates of treatment. As newer therapies become available for HCV, these results may inform further studies and guide strategies to increase treatment rates in all U.S. Veterans and those who experience homelessness.

Rational Design and Adaptive Management of Combination Therapies for Hepatitis C Virus Infection

Recent discoveries of direct acting antivirals against Hepatitis C virus (HCV) have raised hopes of effective treatment via combination therapies. Yet rapid evolution and high diversity of HCV populations, combined with the reality of suboptimal treatment adherence, make drug resistance a clinical and public health concern. We develop a general model incorporating viral dynamics and pharmacokinetics/ pharmacodynamics to assess how suboptimal adherence affects resistance development and clinical outcomes. We derive design principles and adaptive treatment strategies, identifying a high-risk period when missing doses is particularly risky for de novo resistance, and quantifying the number of additional doses needed to compensate when doses are missed. Using data from large-scale resistance assays, we demonstrate that the risk of resistance can be reduced substantially by applying these principles to a combination therapy of daclatasvir and asunaprevir. By providing a mechanistic framework to link patient characteristics to the risk of resistance, these findings show the potential of rational treatment design.

The Hepatitis C treatment experience: Patients' perceptions of the facilitators of and barriers to uptake, adherence and completion

OBJECTIVE

This study explores the perceptions of patients receiving treatment for Hepatitis C to determine what factors influence their decision to commence treatment, ability to maintain adherence and complete their treatment program.

DESIGN

Semi-structured interview techniques were used in a qualitative study of 20 patients undergoing treatment for Chronic Hepatitis C (CHC).

MAIN OUTCOME MEASURES

To explore patients' perceived barriers and facilitators of Hepatitis C treatment adherence and completion.

RESULTS

Analysis of patient interviews identified four key themes: (1) motivations for commencing CHC treatment - fear of death and ridding themselves of stigma and shame; (2) the influential role of provider communication - patients reported that information and feedback that was personalised to their needs and lifestyles was the most effective for improving adherence to treatment; (3) facilitators of treatment adherence and completion - social, emotional and practical support improved adherence and completion, as did temporarily ceasing employment; (4) barriers to treatment adherence and completion - these included side effects, stigma, a complicated dosing schedule and limitations of the public healthcare system.

CONCLUSION

To increase treatment adherence and completion rates, a patient-centred approach is required that addresses patients' social, practical, and emotional support needs and adaptive coping strategies.

Adherence during antiviral treatment regimens for chronic hepatitis C: a qualitative study of patient-reported facilitators and barriers

GOALS

To understand patients' perceptions of factors which facilitate and hinder adherence to inform adherence-enhancing interventions.

BACKGROUND

Adherence to antiviral therapy for hepatitis C viral infection is critical to achieving a sustained virological response. However, persistence with and adherence to antiviral regimens can pose challenges for patients that interfere with sustained virological response.

STUDY

A qualitative analysis of 21 semistructured patient interviews using open-ended questions and specific follow-up probes was conducted. Interviews were audio-recorded, transcribed, and content-analyzed iteratively to determine frequent and salient themes.

RESULTS

Three broad themes emerged: (1) missing doses and dose-timing errors; (2) facilitators of adherence; and (3) barriers to adherence. Open-ended questioning revealed few dose-timing deviations, but more specific probes uncovered several more occurrences of delays in dosing. Facilitators of adherence fell into 2 broad categories: (a) patient knowledge and motivation; and (b) practical behavioral strategies and routines. Facilitators were noted post hoc to be consistent with the Information-Motivation-Behavioral Skills Model of Adherence. Barriers to adherence involved changes in daily routine, being preoccupied with family or work responsibilities, and sleeping through dosing times. A few patients reported skipping doses due to side effects. Patients with previous hepatitis C virus treatment experience may have fewer dose-timing errors. Finally, a high level of anxiety among some patients was discovered regarding dosing errors. Emotional and informational support from clinical and research staff was key to assuaging patient fears.

CONCLUSION

This qualitative study improves our understanding of patients' perspectives regarding adhering to hepatitis C treatment and can lead to the development of adherence-enhancing interventions.

Predicting Discontinuation of Pegylated Interferon as a Result of Lack of Efficacy in United States Veterans With Chronic Hepatitis C on Dual Therapy

BACKGROUND

Many patients with chronic hepatitis C virus (HCV) being treated with pegylated interferon (peg-IFN) plus ribavirin (RBV) do not respond to therapy and do not clear the virus. Standard of care during the era of dual therapy was to discontinue the patient's therapy based on insufficient decreases in viral load after 12 and/or 24 weeks on therapy.

OBJECTIVES

We identified patient characteristics that were significant predictors of discontinuation as a result of lack of efficacy (LOE) in a national database of US veterans with genotypes 1 and 4.

METHODS

We identified US veterans who received care at Veterans Affairs medical centers in 2004-2009 and who had lab-confirmed HCV diagnoses and initiated therapy with peg-IFN plus RBV. Patients who discontinued therapy early were classified as either LOE or non-LOE discontinuers based on pharmacy refill patterns and laboratory response data. Predictors of LOE discontinuation were identified using univariate and multivariable Cox proportional hazards modeling.

RESULTS

Of 321 238 HCV patients with an ICD-9 diagnosis code, 31 215 (9.7%) initiated dual therapy with peg-IFN plus RBV, and 10 333 (3.2%) met all inclusion criteria and were included in the analysis. Overall, 13.6% of the cohort was classified as LOE. Significant predictors of LOE discontinuation included treatment for drug abuse (hazard ratio [HR] = 2.18), age >65 years (HR = 1.75), antiretroviral therapy for HIV (HR = 1.48), black race (HR = 1.47), platelet count >100/mm³ (HR = 1.46), and drug therapy for insomnia (HR = 1.40).

CONCLUSIONS

We identified risk factors for discontinuation caused by LOE. Future work should focus on determining whether these characteristics are also predictive of triple-therapy LOE discontinuations.

Measuring ribavirin concentrations during the earliest stages of antiviral therapy for hepatitis C: potential relevance for treatment outcome

BACKGROUND

Correlations between ribavirin (RBV) concentrations and sustained virological response (SVR) to hepatitis C virus treatment have been demonstrated previously. As steady state is reached after several weeks of RBV treatment, dose modifications based on steady-state levels can only be applied relatively late in treatment, possibly too late to influence SVR rates. The authors aimed to determine whether measurement of early concentrations is useful to predict optimal steady-state RBV concentrations.

METHODS

In 61 treatment-naive genotype 1/4 patients RBV concentrations were determined in samples collected after 1, 2, 4, 8, 12, and 24 weeks of therapy. RBV concentrations were compared between responders and nonresponders; Receiver Operating Characteristic analyses were conducted to find optimal cut-off values to predict week 8 concentrations from earlier measurements.

RESULTS

Median week 8 RBV concentrations were significantly higher in patients with SVR compared with those without: 3.4 (interquartile range 2.4-3.9) versus 2.6 (interquartile range 2.0-3.5) mg/L (P < 0.05). RBV concentration at week 8 was an independent predictor of SVR [adjusted odds ratio 2.3 (95% confidence interval: 1.1-4.9; P = 0.03)]. The optimal cut-off value of week 8 RBV concentration to predict SVR was 2.20 mg/L [sensitivity 87%, specificity 40%, positive predictive value 64%, negative predictive value 71%]. Optimal cut-off values at weeks 1, 2, or 4 to predict an RBV concentration ≥2.20 mg/L at week 8 were 0.92, 1.29, and 1.67 mg/L, respectively, with positive predictive values and negative predictive values ranging from 88% to 91% and 71% to 86%, respectively.

CONCLUSIONS

RBV concentrations in the earliest stages of antiviral therapy predict therapeutic steady-state concentrations, allowing timely dose adjustments with potential implications for treatment outcome.

Treatment of hepatitis C virus infection among people who are actively injecting drugs: a systematic review and meta-analysis

BACKGROUND

Although guidelines recommend that people who inject drugs (PWID) should not be excluded from hepatitis C (HCV) treatment, some services remain reluctant to treat PWID. The aim of this review was to investigate sustained virologic response (SVR), adherence, discontinuation, and HCV reinfection among PWID.

METHODS

A search of Medline, Embase, and Cochrane databases (between 2002 and January 2012) was conducted for primary articles/conference abstracts examining HCV treatment outcomes in PWID. Meta-analysis was used to obtain pooled estimates of SVR, adherence, discontinuation, and HCV reinfection.

RESULTS

Ten primary articles and 1 conference abstract met the inclusion criteria. Across 6 studies (comprising 314 drug users, of whom 141 [45%] were PWID), pooled SVR was 56% (95% confidence interval [CI], 50%-61%) for all genotypes, 37% (95% CI, 26%-48%) for genotypes 1/4, and 67% (95% CI, 56%-78%) for genotypes 2/3. Pooled 80/80/80 adherence was 82% (95% CI, 74%-89%) across 2 studies, and pooled treatment discontinuation was 22% (95% CI, 16%-27%) across 4 studies. Across 5 studies (comprising 131 drug users) examining reinfection, pooled risk was 2.4 (95% CI, .9-6.1) per 100 person-years.

CONCLUSIONS

HCV treatment outcomes are acceptable in PWID, supporting treatment guidelines. The pooled estimate of HCV reinfection risk was low, but there was considerable uncertainty around this estimate. Further studies on the risk of reinfection are needed to assess the long-term effectiveness of HCV treatment in PWID.

Recommendations for the management of hepatitis C virus infection among people who inject drugs

In the developed world, the majority of new and existing hepatitis C virus (HCV) infections occur among people who inject drugs (PWID). The burden of HCV-related liver disease in this group is increasing, but treatment uptake among PWID remains low. Among PWID, there are a number of barriers to care that should be considered and systematically addressed, but these barriers should not exclude PWID from HCV treatment. Furthermore, it has been clearly demonstrated that HCV treatment is safe and effective across a broad range of multidisciplinary healthcare settings. Given the burden of HCV-related disease among PWID, strategies to enhance HCV assessment and treatment in this group are urgently needed. These recommendations demonstrate that treatment among PWID is feasible and provides a framework for HCV assessment, management, and treatment. Further research is needed to evaluate strategies to enhance assessment, adherence, and SVR among PWID, particularly as new treatments for HCV infection become available.

Patient adherence issues in the treatment of hepatitis C

The current standard-of-care treatments for chronic hepatitis C, based on a bitherapy that combines peginterferon alpha-2a or -2b and ribavirin for all genotypes, and on a triple therapy with the addition of an antiprotease specifically for genotype 1, are associated with a limited adherence that decreases their efficacy. The main factors limiting adherence are difficulties in taking the treatment and side effects that worsen the quality of life of the patients. Programs of therapeutic education are essential to improve adherence, quality of life, likelihood of viral suppression, improvement of liver disease, and decrease of late complications. Therapeutic education should be understood as an acquisition of decisional, technical, and social competency with the purpose of making the patient able to make health choices, realize their own life plans, and use health care resources in the best manner. The patient should be placed in the center of an organization, comprising various care workers who include social service professionals and medical staff. For hepatitis C, therapeutic education may be separated into three phases: a first phase corresponding to the educative diagnosis; a second phase corresponding to support during treatment; and the third phase corresponding to support after treatment. Therapeutic education is performed using various instruments and methods specifically adapted to the needs and expectations of individual patients. Upcoming treatments for hepatitis C, with evidence for high efficacy, few side effects, and shorter duration, will certainly change the landscape of adherence and the management of therapeutic education.

Factors associated with uptake, adherence, and efficacy of hepatitis C treatment in people who inject drugs: a literature review

INTRODUCTION AND METHODS

Hepatitis C virus (HCV) infections are highly prevalent amongst people who inject drugs (PWID). Despite well documented evidence of its effectiveness, suggested cost-effectiveness, and potential to reduce HCV prevalence rates, the uptake of antiviral HCV treatment by PWID is low. This nonsystematic literature review describes factors associated with the uptake, adherence, and efficacy of HCV treatment among PWID and discusses strategies to increase their uptake of treatment.

RESULTS

Low HCV treatment uptake among PWID is associated with a number of patient-related and provider-related barriers. Beliefs and fears about low efficacy and adverse effects on the patient's part are common. A substantial number of factors are associated with the chaotic lifestyle and altered social functioning of PWID, which are often associated with decompensation or relapsing into drug addiction. This may lead to perceived low adherence with treatment and low efficacy on the provider's part too, where lack of support, inadequate management of addiction, and other drug-related problems and poor treatment of side effects have been described. Practical issues such as the accessibility of treatment and finances also play a role. Strategies to improve the HCV treatment rate among PWID involve pretreatment management and assessment, a multidisciplinary approach, management of side effects, and enhanced education and counseling.

CONCLUSION

Specific factors are associated with poorer treatment outcomes in PWID on the side of both the patient and the treatment system. However, given that PWID can achieve treatment adherence and sustained virologic response rates comparable with those in nondrug users, drug use per se should not be considered a criterion for exclusion from treatment. Further development of measures leading to higher uptake of treatment and adherence in PWID and appropriate adaptation of HCV treatment guidelines represent important tools in this regard.

Impact of hepatitis C treatment initiation on adherence to concomitant medications

Our study investigated whether initiating hepatitis C virus (HCV) treatment affected adherence to concomitant medications. Mixed-effects linear regression was used to analyze data from 57 patients (29 co-infected with HIV) in a prospective study of HCV treatment-naïve patients initiating HCV treatment. Adherence was assessed using structured self-report at the time of treatment initiation, and at 12 weeks and 24 weeks into treatment. There was no change in adherence to concomitant medications over the first 24 weeks of HCV treatment. There was a significant interaction effect such that the change in adherence to concomitant medications between baseline and 12 weeks differed between the HIV-infected and HIV-uninfected patients. Adherence to concomitant medications in the HIV-infected patients was found to decrease, whereas adherence in the HIV-uninfected patients was found to increase. HIV-infected patients may be more at risk for adherence problems in the first 12 weeks of HCV treatment as compared to HIV-uninfected patients.

Adherence to PEG/ribavirin treatment for chronic hepatitis C: prevalence, patterns, and predictors of missed doses and nonpersistence

Adherence to treatment for hepatitis C virus (HCV) maximizes treatment efficacy. Missed doses and failing to persist on treatment are two patient-level processes that are rarely defined or analysed separately from other factors affecting treatment adherence. We evaluated the prevalence and patterns of missed doses and nonpersistence, and identified patient characteristics associated with these outcomes. Missed doses of ribavirin (RBV) and peginterferon (PEG), measured prospectively in Virahep-C using electronic monitoring technology, were analysed using generalized estimating equations. Cox proportional hazards models analysed time to nonpersistence from baseline to week 24 (N = 401) and from week 24 to 48 in Responders (N = 242). Average proportion of PEG- and RBV-missed doses increased over time from 5% to 15% and 7% to 27%, respectively. Patients who were younger, African-American, unemployed, or unmarried were at greater risk of missing PEG from week 0 to 24; higher baseline depression predicted missing PEG from weeks 24 to 48. Patients who were younger or African-American were more likely to miss daily RBV from weeks 0 to 24; and those without private insurance or employment were more likely to miss RBV from weeks 24 to 48. Fifty-two patients failed to persist on treatment for patient-driven deviations. Predictors of nonpersistence from weeks 0 to 24 included younger age, lower education, public or no insurance, or worse baseline headaches. In conclusion, electronic monitoring and the prospective Virahep-C design afforded a unique opportunity to evaluate missing doses and nonpersistence separately, and identify patients at risk of nonadherence. These processes will be important to investigate as the dosing schedules of antiviral regimens become increasingly complex.

Adherence to assigned dosing regimen and sustained virological response among chronic hepatitis C genotype 1 patients treated with boceprevir plus peginterferon alfa-2b/ribavirin

BACKGROUND

Adherence to therapeutic regimens affects the efficacy of peginterferon alfa (P) and ribavirin (R) therapy in patients with chronic hepatitis C virus genotype 1.

AIM

To determine if medication adherence impacts efficacy [sustained virological response (SVR)] with triple therapy that includes boceprevir (BOC) plus P/R.

METHODS

Adherence was determined in two Phase 3 clinical studies with BOC: SPRINT-2 (previously untreated patients) and RESPOND-2 (patients who failed previous therapy with P/R). Adherence to the assigned duration of the dosing regimen and adherence to the three times a day (t.d.s.) dosing interval of 7-9 h for BOC were assessed by the recording of data from patients' dosing diaries and by the amount of study drug dispensed and returned.

RESULTS

Most patients (63-71%) adhered to ≥80% of their assigned treatment duration and achieved SVR rates of 86-90%. In contrast, patients who adhered to <80% of their assigned treatment duration achieved SVR rates of 8-32% (P < 0.0001), particularly low in patients who failed previous therapy (SVR = 8-15%). Different rates of adherence (<60% to >80%) to the t.d.s. dosing interval (7-9 h) with BOC did not influence the SVR rates (SVR = 60-83%) with the exception of patients who failed previous treatment and adhered to <60% of the t.d.s. dosing interval with BOC (SVR = 48-50%; P = 0.005).

CONCLUSIONS

The achievement of an SVR is more dependent on adherence to the assigned duration of treatment than adherence to the t.d.s. dosing interval with boceprevir. Adherence to >60% of t.d.s. dosing with boceprevir is important in patients who failed previous therapy.

Adherence to chronic hepatitis C treatment regimen: first report from a referral center in iran

BACKGROUND

Various aspects of adherence to HCV treatment such as frequency, risk factors as well as causes of non-adherence, and its real role in clinical and virological outcome of the infected patients have remained largely unknown.

OBJECTIVES

The current study aimed to evaluate patients' adherence to anti-HCV medications in Iran.

MATERIALS AND METHODS

From October 2010 to March 2011, socio-demographic characteristics, features of HCV infection, clinical properties, and habitual history of 190 patients were collected. Adherence of each patient to anti-HCV medications was determined at months 1, 3, and 6 of treatment by self-reporting and pill or empty ampoule counting. Adherence to anti-HCV treatment regimen was determined based on the 80/80/80 rule.

RESULTS

Adherence rate to interferon, ribavirin, or a combination of them over the first 6 months of therapy in Iranian HCV patients measured by both methods of self-reporting and pill counting were 35.4-65.8%, 46.3-56.8%, and 28.4-51.1%, respectively. Delay in receiving new prescription, financial issues, and adverse drug reactions were the most common causes of non-adherence in the patients. Adherence to ribavirin was identified as an independent predictor of achieving the end of treatment response, or sustained virological response.

CONCLUSIONS

The rate of adherence to interferon and ribavirin varied significantly according to the method of calculation. Over the treatment course, adherence to interferon alpha and ribavirin, each or their combination, diminished significantly.

Patient adherence to antiviral treatment for chronic hepatitis B and C: a systematic review

INTRODUCTION

Poor adherence to treatment for various chronic diseases is a frequent phenomenon. Current guidelines for the treatment of chronic hepatitis B (HBV) and hepatitis C (HCV) recommend optimal adherence, since it has been suggested that poor adherence is associated with an increased risk of virological failure. We aimed to give an overview of studies exploring adherence to combination treatment (PEG-interferon plus ribavirin) for HCV and nucleos(t)ide analogues for HBV. Material and methods. A systematic review was conducted using the databases PubMed, Embase, Cochrane Library and Web of Knowledge. Search terms included "adherence" or "compliance" combined with "hepatitis B", "hepatitis C" or "viral hepatitis".

RESULTS

The final selection included 19 studies (13 HCV, 6 HBV). Large differences in patient numbers and adherence assessment methods were found between the various studies. For HCV mean adherence varied from 27 to 97%, whereas the proportion of patients with ≥ 80% adherence varied from 27 to 96%. Mean adherence reported in HBV studies ranged from 81 to 99%, with 66 to 92% of patients being 100% adherent. For both HCV and HBV studies, the highest adherence rates were reported in studies using self-report whereas lower adherence rates were reported in studies using pharmacy claims. Poor adherence to treatment was associated with an increased risk of virological failure.

CONCLUSION

Non-adherence to treatment in chronic viral hepatitis is not a frequent phenomenon. However, given the increased risk of virological failure in poorly adherent patients, clinicians should routinely address adherence issues in all patients treated for chronic viral hepatitis.

High effectiveness of peginterferon alfa-2a plus ribavirin therapy in Korean patients with chronic hepatitis C in clinical practice

Background/Aims

Identifying the impact of a patient's ethnicity on treatment responses in clinical practice may assist in providing individualized treatment regimens for chronic hepatitis C (CHC). The effectiveness of standard peginterferon plus ribavirin therapy and the need for triple combination therapy with protease inhibitors in Koreans remain matters of debate. These issues were investigated in the present study.

Methods

The clinical data of 272 treatment-naïve Korean CHC patients who were treated in a community-based clinical trial (Clinical Trial group; n=51) and in clinical practice (Cohort group; n=221), were analyzed and compared. All were treated with standard protocols of peginterferon alfa-2a plus ribavirin therapy.

Results

For patients with hepatitis C virus (HCV) genotype 1, the sustained virological response (SVR) rates in the Clinical Trial and Cohort groups were 81% (21/26) and 55% (58/106), respectively, by intention-to-treat (ITT) analysis (P=0.02), and 100% (13/13) and 80% (32/40), respectively, in treatment-adherent patients (P=0.18). For patients with HCV genotype 2, the SVR rates in these two groups were 96% (24/25) and 88% (101/115), respectively, by ITT analysis (P=0.31). Adherence and treatment duration were independent predictors of SVR for genotypes 1 and 2, respectively (P<0.01 for each). Korean patients with CHC achieved high SVR rates with peginterferon alfa-2a plus ribavirin in both the clinical trial and clinical practice settings.

Conclusions

Measures to raise adherence to standard therapy in clinical practice may improve the SVR rates in these patients as effectively as adding protease inhibitors, thus obviating the need for the latter.

Anemia management in the era of triple combination therapy for chronic HCV

Boceprevir or telaprevir plus ribavirin (RBV) and pegylated interferon-α (pegIFN-α) is the new standard-of-care therapy for patients who are chronically infected with genotype 1 hepatitis C virus (HCV). The addition of these protease inhibitors to the RBV/pegIFN-α combination regimen has significantly improved rates of sustained virologic response (SVR); however, the incidence of anemia has also increased significantly. Anemia can interfere with patients' quality of life, work productivity, and treatment adherence. Severe anemia can cause morbidity and even mortality. For the management of anemia during triple combination therapy, RBV dose reduction is recommended as an initial course of action. Retrospective analyses of carefully selected patient cohorts suggest that RBV dose reduction does not reduce SVR rates. However, this observation needs to be confirmed in prospective trials with cohorts that more accurately reflect the challenging patients treated in real-world practice. Adequate doses of RBV should be maintained during triple combination therapy, as phase II trials have demonstrated that RBV is essential for attaining optimal SVR rates and preventing viral breakthrough, relapse, and emergence of resistant variants. This roundtable addresses key points related to the management of anemia in the era of triple combination therapy, including the increasing problem of anemia, strategies for anemia management, and the importance of maintaining adequate RBV exposure as part of the HCV treatment regimen.

Evaluation of adherence to oral antiviral hepatitis B treatment using structured questionnaires

AIM

To assess adherence rates to nucleos(t)ide analogues (NUCs) therapy in patients with chronic hepatitis B virus infection and determine factors associated with adherence.

METHODS

The questionnaire study was conducted in the liver clinics at Concord Repatriation General Hospital. All patients who were currently taking one or more NUCs were asked to complete a structured, self-administered 32-item questionnaire. Adherence was measured using visual analogue scales. The patient's treating clinician was also asked to assess their patient's adherence via a structured questionnaire.

RESULTS

A total of 80 patients completed the questionnaire. Sixty six percent of the patients (n = 49) reported optimal adherence whilst 25 (33.8%) graded their adherence to NUCs as suboptimal. Thirty four (43%) patients reported to have omitted taking their NUCs sometime in the past. Recent non-adherence was uncommon. Amongst the patients who reported skipping medications, the most common reason cited was "forgetfulness" (n = 27, 56.25%). Other common reasons included: ran out of medications (n = 5, 10.42%), being too busy (n = 4, 8.33%) and due to a change in daily routine (n = 5, 10.42%). Patients who reported low adherence to other prescription pills were also more likely to miss taking NUCs (P = 0.04). Patients who were under the care of a language-discordant clinician were also more likely to report suboptimal adherence to NUCs (P = 0.04).

CONCLUSION

Adherence rates were much less than that expected by the physician and has potential adverse affect on long term outcome. Communication and education appear central and strategies need to be implemented to improve ongoing adherence.

Ribavirin rather than PEG-interferon pharmacodynamics predict nonresponse to antiviral therapy in naive chronic hepatitis C patients

Twenty to fifty per cent of patients with chronic hepatitis C (CHC) experience nonresponse to current antiviral therapy, which may relate in part to ribavirin or PEG-interferon pharmacodynamics. We evaluated potential relevance of various factors for nonresponse. Two hundred forty-two naive CHC patients who received in a previous trial at least 24 weeks of antiviral therapy, including PEG-interferon alfa-2b and ribavirin, were analysed. Of them, 53% were infected with hepatitis C virus (HCV) genotype 1-4, 71% exhibited high viral load and 32% had severe fibrosis/cirrhosis. After 24 weeks of treatment, 39 patients (16%) were nonresponders. In multivariate analysis, lower serum ribavirin concentrations, HCV genotype 1-4 and higher baseline γ-GT predicted nonresponse. Week-24 ribavirin concentrations (2.2 vs 2.8 mg/L, P < 0.001), average ribavirin doses (14.5 vs 15.2 mg/kg per day, P = 0.03) and week-24 haemoglobin decreases (1.7 vs 2.0 mm, P = 0.02) were lower in nonresponders. Nonresponse rates increased progressively at decreasing ribavirin concentrations: 4%, 11%, 13% and 36% in case of serum ribavirin concentrations ≥4, 3-4, 2-3 and ≤2 mg/L, respectively (P = 0.001). Ribavirin concentrations correlated with both week-24 haemoglobin decreases (r = 0.42, P < 0.001) and ribavirin doses (r = 0.17, P = 0.01). Subgroup analysis in HCV genotype 1-4 patients revealed essentially the same results. Nonresponse was exceptional in HCV genotype 2-3 patients and associated with ribavirin concentrations <2 mg/L. Presumed interferon-related factors (average PEG-interferon doses and decreases in leucocytes, granulocytes, platelets and body weight) did not differ between nonresponders and responders. In conclusion, ribavirin- rather than PEG-interferon-related factors are independent and potentially modifiable predictors of nonresponse in treatment-naive CHC patients.

Rationale and design of a randomized controlled trial of directly observed hepatitis C treatment delivered in methadone clinics

BACKGROUND

Most methadone-maintained injection drug users (IDUs) have been infected with hepatitis C virus (HCV), but few initiate HCV treatment. Physicians may be reluctant to treat HCV in IDUs because of concerns about treatment adherence, psychiatric comorbidity, or ongoing drug use. Optimal HCV management approaches for IDUs remain unknown. We are conducting a randomized controlled trial in a network of nine methadone clinics with onsite HCV care to determine whether modified directly observed therapy (mDOT), compared to treatment as usual (TAU), improves adherence and virologic outcomes among opioid users.

METHODS/DESIGN

We plan to enroll 80 HCV-infected adults initiating care with pegylated interferon alfa-2a (IFN) plus ribavirin, and randomize them to mDOT (directly observed daily ribavirin plus provider-administered weekly IFN) or TAU (self-administered ribavirin plus provider-administered weekly IFN). Our outcome measures are: 1) self-reported and pill count adherence, and 2) end of treatment response (ETR) or sustained viral response (SVR). We will use mixed effects linear models to assess differences in pill count adherence between treatment arms (mDOT v. TAU), and we will assess differences between treatment arms in the proportion of subjects with ETR or SVR with chi square tests. Of the first 40 subjects enrolled: 21 have been randomized to mDOT and 19 to TAU. To date, the sample is 77% Latino, 60% HCV genotype-1, 38% active drug users, and 27% HIV-infected. Our overall retention rate at 24 weeks is 92%, 93% in the mDOT arm and 92% in the TAU arm.

DISCUSSION

This paper describes the design and rationale of a randomized clinical trial comparing modified directly observed HCV therapy delivered in a methadone program to on-site treatment as usual. Our trial will allow rigorous evaluation of the efficacy of directly observed HCV therapy (both pegylated interferon and ribavirin) for improving adherence and clinical outcomes. This detailed description of trial methodology can serve as a template for the development of future DOT programs, and can also guide protocols for studies among HCV-infected drug users receiving methadone for opiate dependence.

Relationship between adherence to hepatitis C virus therapy and virologic outcomes: a cohort study

BACKGROUND

Adherence to therapy with pegylated interferon and ribavirin for hepatitis C virus (HCV) infection has been incompletely examined.

OBJECTIVE

To evaluate the relationship between adherence to HCV therapy and early and sustained virologic response, assess changes in adherence over time, and examine risk factors for nonadherence.

DESIGN

Retrospective cohort study.

SETTING

National Veterans Affairs Hepatitis C Clinical Case Registry.

PATIENTS

5706 HCV-infected patients (genotypes 1, 2, 3, or 4) with at least 1 prescription for both pegylated interferon and ribavirin between 2003 and 2006 and HCV RNA results before and after treatment initiation.

MEASUREMENTS

Adherence was calculated over 12-week intervals by using pharmacy refill data. End points included early virologic response (decrease of ≥2 log(10) HCV RNA at 12 weeks) and sustained virologic response (undetectable HCV RNA 24 weeks after the end of treatment).

RESULTS

Early virologic response increased with higher levels of adherence to ribavirin therapy over the initial 12 weeks (patients with HCV genotype 1 or 4, 25 of 68 [37%] with ≤40% adherence vs. 1367 of 2187 [63%] with 91% to 100% adherence [P < 0.001]; patients with HCV genotype 2 or 3, 12 of 18 [67%] with ≤40% adherence vs. 651 of 713 [91%] with 91% to 100% adherence [P < 0.001]). Among patients with HCV genotype 1 or 4, sustained response increased with higher adherence to ribavirin therapy over the second, third, and fourth 12-week intervals. Results were similar for adherence to interferon therapy. Mean adherence to therapy with interferon and ribavirin decreased by 3.4 and 6.6 percentage points per 12-week interval, respectively (P for trend < 0.001 for each drug). Patients who received growth factors or thyroid medications during treatment had higher mean adherence to antiviral therapy.

LIMITATION

This was an observational study without standardized timing for outcome measurements.

CONCLUSION

Early and sustained virologic responses increased with higher levels of adherence to interferon and ribavirin therapy. Adherence to therapy with both antivirals decreased over time, but more so for ribavirin.

Patient preferences and assessment of likely adherence to hepatitis C virus treatment

To estimate patient preferences for attributes of hepatitis C virus (HCV) treatment and patients' assessment of the likely effect of treatment attributes on treatment adherence, HCV patients ≥18 years old completed an online survey that included nine 2-alternative choice questions. Each choice question was defined by the probability of sustained viral response (Efficacy), injection frequency (Frequency), duration of flu-like symptoms after every injection (Flu), injection device (Device), average number of days of work missed each week (Lost Work Days), probability of reversible hair thinning while on treatment (Alopecia) and probability of developing clinical depression while on treatment (Depression). We estimated a mean relative importance weight for each attribute. Patients also answered three rating questions to assess the extent to which treatment attributes might affect adherence. Hundred and fifty patients completed the survey. Efficacy was the most important attribute with a mean relative importance weight of 10 [95% CI: 7.9-12.1]. The remaining attributes were ranked in order of importance as follows: Depression (4.4 [95% CI: 3.6-5.1]), Flu Days(Frequency×Flu) (3.7 [95% CI: 2.2-5.3]), Lost Work Days (2.9 [95% CI: 2.3-3.5]), Alopecia (1.3 [95% CI: 0.7-1.9]) and Device (1.2 [95% CI: 0.4-2.0]). Patients with prior treatment experience were less likely to indicate that treatment attributes would affect adherence. Patients also indicated that increases in the number of flu days would increase the likelihood of nonadherence to treatment. Sustained viral response is the most important treatment attribute to patients but treatment side effects might affect treatment adherence.

Adherence to treatment for recently acquired hepatitis C virus (HCV) infection among injecting drug users

BACKGROUND & AIMS

Adherence to HCV therapy impacts sustained virological response (SVR) but there are limited data on adherence, particularly among injecting drug users (IDUs). We assessed 80/80 adherence (≥80% of PEG-IFN doses, ≥80% treatment), on-treatment adherence, and treatment completion in a study of treatment of recent HCV infection (ATAHC).

METHODS

Participants with HCV received pegylated interferon (PEG-IFN) alfa-2a (180μg/week, n=74) and those with HCV/HIV received PEG-IFN alfa-2a with ribavirin (n=35), for a planned 24 weeks. Logistic regression analyses were used to identify predictors of PEG-IFN 80/80 adherence.

RESULTS

A total of 109 out of 163 patients received treatment (HCV, n=74; HCV/HIV, n=35), with 75% ever reporting IDU. The proportion with 80/80 PEG-IFN adherence was 82% (n=89). During treatment, 14% missed ≥1 dose (on-treatment adherence=99%). Completion of 0-4, 5-19, 20-23, and all 24 weeks of PEG-IFN therapy occurred in 10% (n=11), 14% (n=15), 6% (n=7) and 70% (n=76) of cases, respectively. Participants with no tertiary education were less likely to have 80/80 PEG-IFN adherence (AOR 0.29, p=0.045). IDU prior to or during treatment did not impact 80/80 PEG-IFN adherence. SVR was higher among those patients with ≥80/80 PEG-IFN adherence (67% vs. 35%, p=0.007), but similar among those with and without missed doses during therapy (73% vs. 60%, p=0.309). SVR in those patients discontinuing therapy between 0-4, 5-19, 20-23, and 24 weeks was 9%, 33%, 43%, and 76%, respectively (p<0.001).

CONCLUSIONS

High adherence to treatment for recent HCV was observed, irrespective of IDU prior to, or during, therapy. Sub-optimal PEG-IFN exposure was mainly driven by early treatment discontinuation rather than missed doses during therapy.

Mechanisms of non-response to antiviral treatment in chronic hepatitis C

Treatment of chronic hepatitis C virus (HCV) infection has substantially evolved over the past decade after the Consensus Conference organized by the European Association for the Study of the Liver in 1999. Since then, the standard of care (SOC) for patients with chronic hepatitis C has been the combination of pegylated interferon (pegIFN) alpha-2a or -2b and ribavirin. In patients infected with HCV genotype 1, by far the most frequent HCV genotype worldwide, such treatment leads to a cure of infection in only 40% to 50% of cases. Several factors have been identified to play a role in the outcome of therapy, including the treatment schedule, disease characteristics, viral, and host factors. Human genetic factors have been identified by a recent landmark discovery. However, these factors only partly explain the ability of IFN and ribavirin therapy to cure HCV infection. Several studies have demonstrated that, in non-responders, interferon-stimulated genes were up-regulated prior to therapy through unclear mechanisms. These findings, together with clinical, biochemical and histological data, may help better identify responders before starting therapy. This becomes particularly important as the standard treatment is physically and economically demanding. The future treatment of patients infected with HCV genotype 1 will be based on the combination of pegIFN and ribavirin with a protease inhibitor, telaprevir or boceprevir. Promising results of this triple combination in phase III clinical trials have been recently reported at the Liver Meeting 2010. With this therapy, higher cure rates will be achieved, but specific issues will be raised, such as the emergence of resistance to the protease inhibitors. The goal of this review is to discuss mechanisms involved in the non-response to current and future standard treatments.

Enhanced adherence to HCV therapy with higher dose ribavirin formulation: final analyses from the ADHERE registry

BACKGROUND

Poor adherence to Hepatitis C virus (HCV) treatment is an important cause of treatment failure. Traditional ribavirin 200 mg (RBV) treatment is associated with a significant daily pill burden. RibaPak (RBP), available as 400 mg and 600 mg ribavirin tablets, offers simplified dosing at two pills daily.

AIM

To examine whether improved adherence was associated with RBP vs. RBV.

METHODS

Accurate Dosing in Hepatitis C: Examining the RibaPak Experience (ADHERE) was a U.S., multi-centre, prospective registry capturing data on adherence with RBP vs. RBV in adults with HCV. Adherence was measured by the proportion of subjects remaining on treatment at weeks 4, 12 and 24; by pill counts; and by the proportion of subjects who took > or = 80% of their prescribed dose.

RESULTS

A total of 503 patients (RBP = 346, RBV = 157) from 33 sites were included. A greater proportion of RBV vs. RBP subjects prematurely discontinued treatment. At 12 and 24 weeks, a greater proportion of RBP vs. RBV subjects took > or = 80% of their prescribed doses (P < 0.05). For patients who remained on treatment, the mean milligrams missed per day was significantly greater for RBV vs. RBP at 24 weeks.

CONCLUSIONS

First line treatment with RBP may offer the best prospect for less discontinuation and improved treatment adherence.