Estimating HCV disease burden - volume 3 (editorial)

History of alcohol use does not predict HCV direct acting antiviral treatment outcomes

BACKGROUND

Hepatitis C virus (HCV) infection and excessive alcohol consumption are leading causes of liver disease worldwide. Direct acting antivirals (DAAs) are well-tolerated treatments for HCV infections with high sustained virologic response (SVR) rates. There are limited data assessing the influence of alcohol use on DAA uptake and cure.

METHODS

We performed a retrospective analysis of patients followed at The Ottawa Hospital Viral Hepatitis Program between January 2014 and May 2020 to investigate the effect of excessive alcohol use history on DAA uptake and SVR rates. Additionally, we evaluated the incidence of concurrent comorbidities and social determinants of health. Predictors of DAA uptake and SVR were assessed by logistic regression.

RESULTS

Excessive alcohol use history was reported in 46.0% (733) of patients. Excessive alcohol use did not predict DAA uptake (OR 1.06, 95% CI 0.71 to 1.57), while employment (OR 2.10, 95% CI 1.29 to 3.42) and recreational drug use (OR 0.62, 95% CI 0.40 to 0.94) were predictors. Employment predicted SVR (OR 2.38, 95% CI 1.68 to 3.36) in those starting treatment. Excessive alcohol use history did not predict SVR.

CONCLUSIONS

History of excessive alcohol use does not influence treatment initiation or SVR. Efforts to improve treatment uptake should shift to focus on the roles of determinants of health such as employment and recreational drug use on treatment initiation.

Making Visible HTLV Infection in a Non-endemic Area of Argentina

In Argentina, the human T-cell lymphotropic virus type 1 (HTLV-1) infection has been documented mainly among blood banks with a prevalence of ~0.02–0.046% for Buenos Aires city, 0.8% for the northeast, and 1% for the northwest; both areas are considered endemic for HTLV-2 and 1, respectively. Policies and specific guidelines for testing blood donors for HTLV are included since 2005. Screening for antibodies is performed at blood banks and confirmatory testing is performed at reference laboratories. There are no specific recommendations for the assistance of communities and individuals affected, nor referral to specialized clinics on the HTLV infection. In 2016, as a strategy of intervention, we opened a specialized clinical attendance in a referral infectious diseases public hospital for the comprehensive approach to patients with HTLV, offering follow-up and counseling for patients and their families for the early diagnosis of HTLV-1/2 and related diseases. During the study, 124 patients with presumptive HTLV positive diagnosis from blood bank, symptomatic patients (SPs), relatives, and descendants visited the unit. A total of 46 patients were HTLV positive (38 HTLV-1 and 8 HTLV-2). There were nine SPs (2 adult T-cell leukemia/lymphoma [ATL] and 7 HTLV-1-associated myelopathy/tropical spastic paraparesis [HAM/TSP]). All patients with HTLV-1 and−2 were offered to study their relatives. Two out of 37 (5.4%) descendants tested were positive for HTLV-1. Sexual partners were studied; among 6 out of 11 couples (54.5%) were found positive (5 HTLV-1 and 1 HTLV-2). Other relatives, such as mothers (1/2) and siblings (1/6), were positive for HTLV-1. According to the place of birth among HTLV-1 carriers, 58% were born in an endemic area or in countries where HTLV infection is considered endemic while for HTLV-2 carriers, 12.5% were born in an endemic area of Argentina. The proviral load (pVL) was measured in all, patients with HTLV-1 being higher in symptomatic compared with asymptomatic carriers. In addition, two pregnant women were early diagnosed during their puerperium and breastmilk replacement by formula was indicated. Inhibition of lactation was also indicated. Our study provides tools for a multidisciplinary approach to the infection and reinforces the importance of having specialized clinical units in neglected diseases, such as HTLV for counseling, clinical and laboratory follow-up, and providing useful information for patients for self-care and that of their families.

Forecasting the Incremental Value to Society Created by a Class of New Prescription Drugs: A Proposed Methodology and Its Application to Treating Chronic Hepatitis C in India

BACKGROUND

For low- and middle-income countries, the forecasted incremental value to society created by a class of new prescription drugs would be a useful criterion to prioritize the licensing, subsidization, and provision of new drugs.

OBJECTIVES

We provide a methodology to forecast the value of a new class of drugs, defined as the incremental value obtained in the scenario in which the new class of drugs is available along with existing drugs compared with the scenario of existing drugs only. We forecasted the value created by direct-acting antiviral drugs to treat chronic hepatitis C in India.

METHOD

We conducted a physician survey together with an aggregate multinomial logit model to forecast for each patient type the fraction of physicians who would prescribe the new drug under different scenarios. Value was determined by the monetary equivalent of increased life expectancy, reduced disability, and decreased future infection of others, minus drug cost, all treatment-related costs, and the cost of side effects.

RESULTS

We forecasted that the introduction of direct-acting antiviral drugs is likely to create USD11.5 billion of value in India over a 5-year period, based on a 'realistic' assumption about the growth rate of India's per capita GDP. Under 'pessimistic' and 'optimistic' assumptions about the growth rate, the value changes to USD6.5 and 22.5 billion, respectively.

CONCLUSIONS

There is major value likely to be created by the new direct-acting antiviral drugs in treating hepatitis C in India; this is consistent with the Indian Government's decision to provide the drugs free of cost.

Effectiveness of retreatment with ombitasvir/paritaprevir/ritonavir and dasabuvir+sofosbuvir+ribavirin in patients with chronic hepatitis C, subtype 1b, and cirrhosis, who failed previous treatment with first- and second-generation NS5A inhibitors

The use of direct-acting antiviral agents (DAAs) in patients with chronic HCV genotype (GT) 1 infection results in sustained virologic response (SVR) rates of 95%-97%, but 3%-5% of patients experience virologic failure. We observed 41 patients infected with HCV subtype 1b who failed previous treatment with DAAs, including 37 subjects (90.2%) with liver cirrhosis. In total, 30 (73.2%) subjects previously received NS5A inhibitors of the first generation (ledipasvir, daclatasvir, or ombitasvir) and 11 subjects (26.8%) received NS5A inhibitors of the second generation (velpatasvir). All patients received retreatment with a combination of ombitasvir/paritaprevir/ritonavir and dasabuvir (3D) with sofosbuvir (SOF) and ribavirin (RBV). We compared SVR12 rates depending on fibrosis stage, presence of just single or double NS5A mutation (L31M/V/I and/or Y93H), and the generation of previously used NS5A inhibitors. Observed SVR12 rates were as follows: 97.6% (40/41 patients) overall; 100% in patients without cirrhosis (n = 4) versus 97.3% in those with cirrhosis (n = 37); 100% with single L31M/V/I or Y93H mutation (n = 22) versus 94.4% with double mutations (n = 18); 100% in patients who failed previous treatment with first-generation (n = 30) versus 90.9% in those who failed previous treatment with second-generation NS5A inhibitors (n = 11). Retreatment with 3D + SOF + RBV was highly effective and safe in patients with chronic HCV GT1b infection, including those with liver cirrhosis, who failed previous treatment with DAA containing NS5A inhibitors. Fibrosis stage and single or simultaneous presence of NS5A RASs L31M/V/I and Y93H at the baseline, as well as the generation of previously used NS5A inhibitors, did not impact SVR12 rates.

What do clinicians need to watch for with direct-acting antiviral therapy?

Introduction

The introduction of drugs targeting the virus replication cycle has revolutionized treatment of chronic hepatitis C virus. These drugs, called direct‐acting antivirals, have brought about extremely high rates of virological cure and have increased the number of patients who can receive treatment due to the lack of absolute contraindications. A combination of different classes of direct‐acting antivirals is the current standard of care. Although treatment administration and monitoring has been simplified in recent years, it is still relatively complex and mostly in the hands of specialists. Several factors must be assessed before starting treatment to maximize efficacy and minimize side effects of treatment. In this review, we describe the factors that impact on the efficacy and safety of antiviral treatment for hepatitis C and provide clear recommendations for clinicians prescribing direct‐acting antivirals.

Methods

We reviewed literature to define best practice, based on factors associated with treatment efficacy and safety data to recommend treatment options, baseline and on‐treatment assessments. The review included searches in PubMed, and the abstracts presented at the International Liver Congress TM and The Liver Meeting TM between January 2013 and September 2017.

Results

Clinical features that must be assessed before starting treatment include virological factors, such as hepatitis C virus genotype, HIV and hepatitis B coinfection and host factors, such as concomitant medications, liver disease stage and renal function.

Conclusions

Patients who start antiviral treatment for chronic hepatitis C require a thorough clinical evaluation. There is a need for assessing factors that impact on the treatment schedule and duration or affect the pharmacokinetics of direct‐acting antivirals.

Hepatitis delta and HIV infection

Viral liver diseases are frequent comorbidities and major contributors to death in HIV-positive individuals on antiretroviral therapy. Although cure of hepatitis C and control of hepatitis B with antivirals avert liver disease progression in most HIV-coinfected patients, the lack of satisfactory treatment for hepatitis delta virus (HDV) infection remains a major threat for developing cirrhosis and liver cancer in this population. In the European Union (EU) and North America, sexual contact has replaced injection drug use that has been the major transmission route for HDV in HIV-positive persons. PegIFNα is the only approved HDV therapy; however, sustained HDV-RNA clearance is achieved by less than 25%. The recent discovery of sodium taurocholate cotransporting polypeptide as the key hepatitis B virus (HBV) and HDV cell entry receptor has opened the door to a new therapeutic era. Indeed, promising results have been released using Myrcludex-B, a sodium taurocholate cotransporting polypeptide inhibitor. More encouraging are data with new classes of HDV blockers, such as prenylation inhibitors (i.e. lonafarnib) and nucleic acid polymers. At this time, sustained suppression of HDV replication is the primary goal of HDV therapy, as it is associated with normalization of liver enzymes and histological improvement. Of note, the use of specific antivirals for HDV must be given along with anti-HBV agents to prevent HBV rebounds following removal of viral interference. The lack of persistent forms of HDV-RNA could provide a unique opportunity for curing hepatitis delta, even without eliminating HBV circular covalently closed DNA. Ultimately, suppression of HDV replication along with hepatitis B surface antigen clearance once drugs are off would be the best reflect of hepatitis delta cure.

Fatty liver is associated with an increased risk of diabetes and cardiovascular disease - Evidence from three different disease models: NAFLD, HCV and HIV

Fatty liver, which frequently coexists with necro-inflammatory and fibrotic changes, may occur in the setting of nonalcoholic fatty liver disease (NAFLD) and chronic infections due to either hepatitis C virus (HCV) or human immunodeficiency virus (HIV). These three pathologic conditions are associated with an increased prevalence and incidence of cardiovascular disease (CVD) and type 2 diabetes (T2D). In this multidisciplinary clinical review, we aim to discuss the ever-expanding wealth of clinical and epidemiological evidence supporting a key role of fatty liver in the development of T2D and CVD in patients with NAFLD and in those with HCV or HIV infections. For each of these three common diseases, the epidemiological features, pathophysiologic mechanisms and clinical implications of the presence of fatty liver in predicting the risk of incident T2D and CVD are examined in depth. Collectively, the data discussed in this updated review, which follows an innovative comparative approach, further reinforce the conclusion that the presence of fatty/inflamed/fibrotic liver might be a shared important determinant for the development of T2D and CVD in patients with NAFLD, HCV or HIV. This review may also open new avenues in the clinical and research arenas and paves the way for the planning of future, well-designed prospective and intervention studies.

Hepatitis C: global epidemiology and strategies for control

It is estimated that globally there are approximately 100 million persons with serological evidence of current or past HCV infection, and that HCV causes about 700 000 deaths each year. The prevalence of infection is the highest in lower and middle income countries, in which a significant number of past infections were caused by iatrogenic transmission and sub-optimal injection safety. In contrast, in developed countries, infections are caused mainly by high-risk exposures and behaviours among specific populations, such as persons who inject drugs. Recently, new direct antiviral activity (DAA) oral drugs with high rates of cure over short duration, which are well tolerated, have made chronic hepatitis C a curable condition. The extraordinary clinical performance of DAAs and recent substantial price reductions and expansion in access in resource-limited settings has provided new impetus for potential control and elimination of hepatitis C as a public health threat. We review the global epidemiology of HCV and the opportunities for preventative and treatment interventions to achieve global control of HCV infection. We also summarize the key elements of the World Health Organization's first-ever global health sector strategy for addressing the viral hepatitis pandemic.