Stephen T. Barclay

Toward a more complete understanding of the association between a hepatitis C sustained viral response and cause-specific outcomes

Sustained viral response (SVR) is the optimal outcome of hepatitis C virus (HCV) therapy, yet more detailed data are required to confirm its clinical value. Individuals receiving treatment in 1996‐2011 were identified using the Scottish HCV clinical database. We sourced data on 10 clinical events: liver, nonliver, and all‐cause mortality; first hospitalisation for severe liver morbidity (SLM); cardiovascular disease (CVD); respiratory disorders; neoplasms; alcohol‐intoxication; drug intoxication; and violence‐related injury (note: the latter three events were selected a priori to gauge ongoing chaotic lifestyle behaviours). We determined the association between SVR attainment and each outcome event, in terms of the relative hazard reduction and absolute risk reduction (ARR). We tested for an interaction between SVR and liver disease severity (mild vs. nonmild), defining mild disease as an aspartate aminotransferase‐to‐platelet ratio index (APRI) <0.7. Our cohort comprised 3,385 patients (mean age: 41.6 years), followed‐up for a median 5.3 years (interquartile range: 3.3‐8.2). SVR was associated with a reduced risk of liver mortality (adjusted hazard ratio [AHR]: 0.24; P < 0.001), nonliver mortality (AHR, 0.68; P = 0.026), all‐cause mortality (AHR, 0.49; P < 0.001), SLM (AHR, 0.21; P < 0.001), CVD (AHR, 0.70; P = 0.001), alcohol intoxication (AHR, 0.52; P = 0.003), and violence‐related injury (AHR, 0.51; P = 0.002). After 7.5 years, SVR was associated with significant ARRs for liver mortality, all‐cause mortality, SLM, and CVD (each 3.0%‐4.7%). However, we detected a strong interaction, in that ARRs were considerably higher for individuals with nonmild disease than for individuals with mild disease. Conclusions: The conclusions are 3‐fold: (1) Overall, SVR is associated with reduced hazard for a range of hepatic and nonhepatic events; (2) an association between SVR and behavioral events is consistent with SVR patients leading healthier lives; and (3) the short‐term value of SVR is greatest for those with nonmild disease. (Hepatology 2015;62:355–364

Quantifying the fraction of cirrhosis attributable to alcohol among chronic hepatitis C virus patients: Implications for treatment cost‐effectiveness

A substantial baseline risk of liver cirrhosis exists for patients with chronic hepatitis C virus (HCV) infection. However, the extent to which this could be driven by heavy alcohol use is unclear. Therefore, our principal aim was to determine the fraction of cirrhosis attributable to heavy alcohol use among chronic HCV patients attending a liver clinic. The study population comprised chronic HCV patients who had attended one of five liver clinics in Scotland during 1996‐2010 and had (1) remained in follow‐up for at least 6 months, (2) acquired HCV through either injecting drugs or blood transfusion, and (3) an estimated date of acquiring infection. Predictors of cirrhosis were determined from multivariate logistic regression. Regression parameters were used to determine the fraction of cirrhosis attributable to heavy alcohol use. Among 1,620 patients, 9% were diagnosed with cirrhosis, and 34% had ever engaged in heavy alcohol use (>50 units/week for a sustained period). Significant predictors of cirrhosis were age, duration of infection, and ever heavy alcohol use. The fraction of cirrhosis attributable to ever heavy alcohol use was 36.1% (95% confidence interval [CI]: 24.4‐47.4). Moreover, among patients who had ever engaged in heavy alcohol use specifically, this attributable fraction exceeded 50% (61.6%; 95% CI: 47.0‐72.2). Conclusions: A substantial proportion of patients with chronic HCV develop liver cirrhosis as a consequence of heavy alcohol use. This has not been adequately acknowledged by cost utility analyses (CUAs). As such, estimates of cost‐effectiveness may be exaggerated. Thus, these data are important to guide forthcoming CUAs in terms of taking better account of the factors leading to cirrhosis among patients with chronic HCV. (HEPATOLOGY 2013)

Review article: 2014 UK consensus guidelines – hepatitis C management and direct‐acting anti‐viral therapy

Therapeutic options for the management of hepatitis C virus (HCV) infection have evolved rapidly over the past two decades, with a consequent improvement in cure rates. Novel therapeutic agents are an area of great interest in the research community, with a number of these agents showing promise in the clinical setting.

Hepatitis C reinfection following treatment induced viral clearance among people who have injected drugs.

BACKGROUND Although people who inject drugs (PWID) are an important group to receive Hepatitis C Virus (HCV) antiviral therapy, initiation onto treatment remains low. Concerns over reinfection may make clinicians reluctant to treat this group. We examined the risk of HCV reinfection among a cohort of PWID (encompassing all those reporting a history of injecting drug use) from Scotland who achieved a sustained virological response (SVR). METHODS Clinical and laboratory data were used to monitor RNA testing among PWID who attained SVR following therapy between 2000 and 2009. Data were linked to morbidity and mortality records. Follow-up began one year after completion of therapy, ending on 31st December, 2012. Frequency of RNA testing during follow-up was calculated and the incidence of HCV reinfection estimated. Cox proportional hazards regression was used to examine factors associated with HCV reinfection. RESULTS Among 448 PWID with a SVR, 277 (61.8%) were tested during follow-up, median 4.5 years; 191 (69%) received one RNA test and 86 (31%) received at least two RNA tests. There were seven reinfections over 410 person years generating a reinfection rate of 1.7/100py (95% CI 0.7-3.5). For PWID who have been hospitalised for an opiate or injection related cause post SVR (11%), the risk of HCV reinfection was greater [AHR=12.9, 95% CI 2.2-76.0, p=0.002] and the reinfection rate was 5.7/100py (95% CI 1.8-13.3). CONCLUSION PWID who have been tested, following SVR, for HCV in Scotland appear to be at a low risk of reinfection. Follow-up and monitoring of this population are warranted as treatment is offered more widely.

Uptake of hepatitis C specialist services and treatment following diagnosis by dried blood spot in Scotland

BACKGROUND Dried blood spot (DBS) testing for hepatitis C (HCV) was introduced to Scotland in 2009. This minimally invasive specimen provides an alternative to venipuncture and can overcome barriers to testing in people who inject drugs (PWID). OBJECTIVES The objective of this study was to determine rates and predictors of: exposure to HCV, attendance at specialist clinics and anti-viral treatment initiation among the DBS tested population in Scotland. STUDY DESIGN DBS testing records were deterministically linked to the Scottish HCV Clinical database prior to logistic regression analysis. RESULTS In the first two years of usage in Scotland, 1322 individuals were tested by DBS of which 476 were found to have an active HCV infection. Linkage analysis showed that 32% had attended a specialist clinic within 12 months of their specimen collection date and 18% had begun anti-viral therapy within 18 months of their specimen collection date. A significantly reduced likelihood of attendance at a specialist clinic was evident amongst younger individuals (<35 years), those of unknown ethnic origin and those not reporting injecting drug use as a risk factor. CONCLUSION We conclude that DBS testing in non-clinical settings has the potential to increase diagnosis and, with sufficient support, treatment of HCV infection among PWID.

Mortality in hepatitis C patients who achieve a sustained viral response compared to the general population

BACKGROUND & AIMS The number of people living with previous hepatitis C infection that have attained a sustained viral response (SVR) is expected to grow rapidly. So far, the prognosis of this group relative to the general population is unclear. METHODS Individuals attaining SVR in Scotland in 1996-2011 were identified using a national database. Through record-linkage, we obtained cause-specific mortality data complete to Dec 2013. We calculated standardised mortality ratios (SMRs) to compare the frequency of mortality in SVR patients to the general population. In a parallel analysis, we used Cox regression to identify modifiable patient characteristics associated with post-SVR mortality. RESULTS We identified 1824 patients, followed on average for 5.2years after SVR. In total, 78 deaths were observed. Overall, all-cause mortality was 1.9 times more frequent for SVR patients than the general population (SMR: 1.86; 95% confidence interval (CI): 1.49-2.32). Significant cause-specific elevations were seen for death due to primary liver cancer (SMR: 23.50; 95% CI: 12.23-45.16), and death due to drug-related causes (SMR: 6.58, 95% CI: 4.15-10.45). Together these two causes accounted for 66% of the total excess death observed. All of the modifiable characteristics associated with increased mortality were markers either of heavy alcohol use or injecting drug use. Individuals without these behavioural markers (32.8% of cohort) experienced equivalent survival to the general population (SMR: 0.70; 95% CI: 0.41-1.18) CONCLUSIONS: Mortality in Scottish SVR patients is higher overall than the general population. The excess was driven by death from drug-related causes and liver cancer. Health risk behaviours emerged as important modifiable determinants of mortality in this population. LAY SUMMARY Patients cured of hepatitis C through treatment had a higher mortality rate overall than the general population. Most of the surplus mortality was due to drug-related causes and death from liver cancer. A history of heavy alcohol and injecting drug use were associated with a higher mortality risk.

Evidence of continued injecting drug use after attaining sustained treatment-induced clearance of the hepatitis C virus: implications for reinfection

BACKGROUND People who inject drugs (PWID) are at the greatest risk of hepatitis C virus (HCV) infection, yet are often denied immediate treatment due to fears of on-going risk behaviour. Our principal objective was to examine evidence of continued injecting drug use among PWID following successful treatment for HCV and attainment of a sustained viral response (SVR). METHODS PWID who attained SVR between 1992 and June 2012 were selected from the National Scottish Hepatitis C Clinical Database. Hospitalisation and mortality records were sourced for these patients using record linkage techniques. Our primary outcome variable was any hospitalisation or death, which was indicative of injecting drugs post-SVR. RESULTS The cohort comprised 1170 PWID (mean age at SVR 39.6y; 76% male). The Kaplan Meier estimate of incurring the primary outcome after three years of SVR was 10.59% (95% CI, 8.75-12.79) After adjusting for confounding, the risk of an injection related hospital episode or death post-SVR was significantly increased with advancing year of SVR: AHR:1.07 per year (95% CI, 1.01-1.14), having a pre-SVR acute alcohol intoxication-related hospital episode: AHR:1.83 (95% CI, 1.29-2.60), and having a pre-SVR opiate or injection-related hospital episode: AHR:2.59 (95% CI, 1.84-3.64). CONCLUSION Despite attaining the optimal treatment outcome, these data indicate that an increasing significant minority of PWID continue to inject post-SVR at an intensity which leads to either hospitalisation or death and increased risk of reinfection.

Broad anti-hepatitis C virus (HCV) antibody responses are associated with improved clinical disease parameters in chronic HCV infection

ABSTRACT During hepatitis C virus (HCV) infection, broadly neutralizing antibody (bNAb) responses targeting E1E2 envelope glycoproteins are generated in many individuals. It is unclear if these antibodies play a protective or a pathogenic role during chronic infection. In this study, we investigated whether bNAb responses in individuals with chronic infection were associated with differences in clinical presentation. Patient-derived purified serum IgG was used to assess the breadth of HCV E1E2 binding and the neutralization activity of HCV pseudoparticles. The binding and neutralization activity results for two panels bearing viral envelope proteins representing either an intergenotype or an intragenotype 1 group were compared. We found that the HCV load was negatively associated with strong cross-genotypic E1E2 binding (P = 0.03). Overall, we observed only a modest correlation between total E1E2 binding and neutralization ability. The breadth of intergenotype neutralization did not correlate with any clinical parameters; however, analysis of individuals with genotype 1 (gt1) HCV infection (n = 20), using an intragenotype pseudoparticle panel, found a strong association between neutralization breadth and reduced liver fibrosis (P = 0.006). A broad bNAb response in our cohort with chronic infection was associated with a single nucleotide polymorphism (SNP) in the HLA-DQB1 gene (P = 0.038), as previously reported in a cohort with acute disease. Furthermore, the bNAbs in these individuals targeted more than one region of E2-neutralizing epitopes, as assessed through cross-competition of patient bNAbs with well-characterized E2 antibodies. We conclude that the bNAb responses in patients with chronic gt1 infection are associated with lower rates of fibrosis and host genetics may play a role in the ability to raise such responses. IMPORTANCE Globally, there are 130 million to 150 million people with chronic HCV infection. Typically, the disease is progressive and is a major cause of severe liver cirrhosis and hepatocellular carcinoma. While it is known that neutralizing antibodies have a role in spontaneous clearance during acute infection, little is known about their role in chronic infection. In the present work, we investigated the antibody response in a cohort of chronically infected individuals and found that a broadly neutralizing antibody response is protective and is associated with reduced levels of liver fibrosis and cirrhosis. We also found an association between SNPs in class II HLA genes and the presence of a broadly neutralizing response, indicating that antigen presentation may be important for the production of HCV-neutralizing antibodies.

A matched comparison study of hepatitis C treatment outcomes in the prison and community setting, and an analysis of the impact of prison release or transfer during therapy

Prisoners are a priority group for hepatitis C (HCV) treatment. Although treatment durations will become shorter using directly acting antivirals (DAAs), nearly half of prison sentences in Scotland are too short to allow completion of DAA therapy prior to release. The purpose of this study was to compare treatment outcomes between prison‐ and community‐based patients and to examine the impact of prison release or transfer during therapy. A national database was used to compare treatment outcomes between prison treatment initiates and a matched community sample. Additional data were collected to investigate the impact of release or transfer on treatment outcomes. Treatment‐naïve patients infected with genotype 1/2/3/4 and treated between 2009 and 2012 were eligible for inclusion. 291 prison initiates were matched with 1137 community initiates: SVRs were 61% (95% CI 55%–66%) and 63% (95% CI 60%–66%), respectively. Odds of achieving a SVR were not significantly associated with prisoner status (P=.33). SVRs were 74% (95% CI 65%–81%), 59% (95% CI 42%–75%) and 45% (95% CI 29%–62%) among those not released or transferred, transferred during treatment, or released during treatment, respectively. Odds of achieving a SVR were significantly associated with release (P<.01), but not transfer (P=.18). Prison‐based HCV treatment achieves similar outcomes to community‐based treatment, with those not released or transferred during treatment doing particularly well. Transfer or release during therapy should be avoided whenever possible, using anticipatory planning and medical holds where appropriate.

What is the impact of a country-wide scale-up in antiviral therapy on the characteristics and sustained viral response rates of patients treated for hepatitis C?

BACKGROUND & AIMS The global burden associated with hepatitis C virus (HCV) infection has prompted a scale-up of antiviral therapy. Hitherto, no data exist on the impact of scaling-up, on the characteristics of treated populations, or on sustained viral response (SVR) rates. We assessed the country-wide scale-up of antiviral therapy in Scotland, a country which nationally monitors uptake of and response to HCV treatment. METHODS Data for patients, initiated on combined pegylated interferon and ribavirin therapy at 13 specialist HCV clinics in 2001-2010, were extracted from the Scottish HCV Clinical Database (n=3895). Patient characteristics included age, genotype, PWID (people who inject drugs) status, prison referral, and diagnosed cirrhosis. Temporal trends in covariates and adjusted effects on a SVR were examined via mixed-effects regression. RESULTS The number of patients starting treatment increased from 237 in 2001-2002 to 1560 in 2009-2010, with an increasing trend in SVR from 44% to 57% over this period. For a given clinic, between 2001/2 and 2010 there was a decrease in the odds of those treated being diagnosed with cirrhosis (odds ratio [OR]=0.84 per year), and increasing temporal trends for those treated being PWID (OR=1.08) and prison referrals (OR=1.06). Adjusting for covariates, the proportion of a given clinics patients achieving SVR was positively associated with the percentage of PWID (OR=1.01 per percent increase; 95% confidence interval [CI]: 1.00-1.02) and genotype 2/3 (OR=1.03; 95% CI: 1.02-1.04). CONCLUSIONS Despite changes in patient characteristics, a country-wide scale-up of antiviral therapy did not compromise SVR rates. Results are highly relevant to countries planning on scaling-up treatment, given the forthcoming availability of new interferon-free therapies.