A French prospective observational study of the treatment of chronic hepatitis C in drug abusers

Integrated Care for the Use of Direct-acting Antivirals in Patients With Chronic Hepatitis C and Substance Use Disorder

OBJECTIVES

Since little is currently known about predictors of response to direct-acting antiviral agents (DAAs) in people who inject drugs, we undertook an analysis of patients attending a hepatitis clinic with addiction services (outpatient clinics and inpatient services) to examine the outcomes associated with the treatment of difficult-to-manage patients with substance use. Our experience was based on integrated care.

METHOD

A retrospective analysis was undertaken of 50 patients with hepatitis C virus (HCV) and a history of addiction who received treatment with DAAs, according to European guidelines. These regimens were sofosbuvir/ledipasvir for 8 weeks (n = 3), sofosbuvir/ledipasvir ± ribavirin for 12 weeks (n = 19), sofosbuvir/daclatasvir for 12 weeks (n = 20), sofosbuvir/simeprevir (n = 1), or sofosbuvir/daclatasvir for 24 weeks (n = 7). Characteristics of patients who did versus did not achieve a sustained virologic response (SVR) 12 weeks after treatment were compared by univariate analysis.

RESULTS

Forty-two patients (84%) were male; mean age was 46.2 ± 7.3 years. Genotypes were 1 (n = 21), 2 (n = 4), 3 (n = 18), 4 (n = 6), or 6 (n = 1). Most patients were treatment-naïve (n = 38). Five patients had coinfection with human immunodeficiency virus (n = 4) or hepatitis B (n = 1), 28 (56%) had evidence of cirrhosis on FibroScan (>12.5 kPa), and 34 (68%) were receiving opioid substitution therapy. Psychiatric disease, illicit drug use, unemployment, and homelessness/precarious housing were common. Forty-five patients (90%) achieved SVR, 2 were lost to follow-up, and 3 had treatment relapse.

CONCLUSIONS

SVR was not significantly associated with sociodemographic or virological characteristics, treatment, social environment, alcohol/drug use, and adherence. Although adherence was slightly worse than in "usual" patients, it did not affect the SVR rate. In these difficult-to-manage patients with HCV and substance use disorder, the real-world SVR rate (90%) was similar to that in nonaddicted populations.

Hepatitis C virus treatment in the real world: optimising treatment and access to therapies

Chronic HCV infections represent a major worldwide public health problem and are responsible for a large proportion of liver related deaths, mostly because of HCV-associated hepatocellular carcinoma and cirrhosis. The treatment of HCV has undergone a rapid and spectacular revolution. In the past 5 years, the launch of direct acting antiviral drugs has seen sustained virological response rates reach 90% and above for many patient groups. The new treatments are effective, well tolerated, allow for shorter treatment regimens and offer new opportunities for previously excluded groups. This therapeutic revolution has changed the rules for treatment of HCV, moving the field towards an interferon-free era and raising the prospect of HCV eradication. This manuscript addresses the new challenges regarding treatment optimisation in the real world, improvement of antiviral efficacy in 'hard-to-treat' groups, the management of patients whose direct acting antiviral drug treatment was unsuccessful, and access to diagnosis and treatment in different parts of the world.

Drug-Drug Interactions With Antiviral Agents in People Who Inject Drugs Requiring Substitution Therapy

OBJECTIVE

To describe potential drug-drug interactions in the area of HIV/hepatitis C virus (HCV) coinfection and injection drug use, including those between antiretrovirals (ARVs), direct-acting antivirals (DAAs), and opioid-agonist therapy, and to supply a practical approach to their management.

DATA SOURCES

We searched PubMed for relevant articles published up until February 2015 as well as conference reports and drug-drug-interaction Web sites.

DATA SELECTION AND DATA EXTRACTION

We used the following search terms: pharmacokinetic and pharmacodynamic drug-drug interaction, opioid substitution, HIV, hepatitis and the individual names of the relevant agents of the following drug classes and the drug classes itself: reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors, protease inhibitors, direct-acting antivirals, opioide, benzodiazepines, anticonvulsants, antidepressants and antipsychotics. Additional references were identified from a review of literature citations and drug-drug interaction Web sites. In our evaluation, we included German- and English-language studies and reports addressing drug-drug interactions between opioid agonist therapy and ARVs or DAAs.

DATA SYNTHESIS

Pharmacokinetic data were available for all ARVs and DAAs except rilpivirine, indinavir, saquinavir, maraviroc, dolutegravir, and MK-8742 with buprenorphine as well as maraviroc with methadone Drug-drug interactions of potential clinical relevance are most likely to occur between opioid-replacement therapy and ARVs, particularly the nonnucleoside reverse transcriptase inhibitors, efavirenz and nevirapine, and HIV protease inhibitors.

CONCLUSION

Integrase inhibitors may be safely coadministered with opioid-replacement therapy. With respect to HCV DAAs, most currently approved and late-stage investigational agents do not have clinically significant interactions with opioid-replacement therapy. ARV and DAAs may interact with other drug classes commonly used in the opioid-dependent population, including benzodiazepines, antidepressants, anticonvulsants, and antipsychotics.

Eligibility of persons who inject drugs for treatment of hepatitis C virus infection

In this decade, an increase is expected in end-stage liver disease and hepatocellular carcinoma, most commonly caused by hepatitis C virus (HCV) infection. Although people who inject drugs (PWID) are the major source for HCV infection, they were excluded from antiviral treatments until recently. Nowadays there is incontrovertible evidence in favor of treating these patients, and substitution therapy and active substance use are no longer contraindications for antiviral treatment. The viral clearance in PWID after HCV antiviral treatment with interferon or pegylated interferon combined with ribavirin is comparable to the viral clearance in non-substance users. Furthermore, multidisciplinary approaches to delivering treatment to PWID are advised, and their treatment should be considered on an individualized basis. To prevent the spread of HCV in the PWID community, recent active PWID are eligible for treatment in combination with needle exchange programs and substitution therapy. As the rate of HCV reinfection is low after HCV antiviral treatment, there is no need to withhold HCV treatment due to concerns about reinfection alone. Despite the advances in treatment efficacies and data supporting their success, HCV assessment of PWID and initiation of antiviral treatment remains low. However, the proportion of PWID assessed and treated for HCV is increasing, which can be further enhanced by understanding the barriers to and facilitators of HCV care. Removing stigmatization and implementing peer support and group treatment strategies, in conjunction with greater involvement by nurse educators/practitioners, will promote greater treatment seeking and adherence by PWID. Moreover, screening can be facilitated by noninvasive methods for detecting HCV antibodies and assessing liver fibrosis stages. Recently, HCV clearance has become a major endpoint in the war against drugs for the Global Commission on Drug Policy. This review highlights the most recent evidence concerning HCV infection and treatment strategies in PWID.

Buprenorphine for human immunodeficiency virus/hepatitis C virus-coinfected patients: does it serve as a bridge to hepatitis C virus therapy?

OBJECTIVES

Buprenorphine is associated with enhanced human immunodeficiency virus (HIV) treatment outcomes including increased antiretroviral therapy initiation rates, adherence, and CD4 cell counts among HIV-infected opioid-dependent individuals. Buprenorphine facilitates hepatitis C virus (HCV) treatment in opioid-dependent patients with HCV monoinfection. Less is known about buprenorphine's role in HIV/HCV coinfection.

METHODS

We conducted a retrospective chart review to evaluate HCV care for HIV-infected buprenorphine patients in the first 4 years of buprenorphine's integration into a Rhode Island HIV clinic.

RESULTS

Sixty-one patients initiated buprenorphine. All had HCV antibody testing; 57 (93%) were antibody-positive. All antibody-positive patients underwent HCV RNA testing; 48 (84%) were RNA-positive. Of these, 15 (31%) were not referred to HCV care. Among chronically infected patients, 3 received HCV treatment after buprenorphine; all had cirrhosis and none achieved viral eradication. At buprenorphine induction, most patients had inadequately controlled HIV infection, with detectable HIV RNA (59%) or CD4 cell count less than or equal to 350/μL (38%).

CONCLUSIONS

Buprenorphine has shown limited success to date as a bridge to HCV treatment within an HIV clinic. Buprenorphine's stabilization of opioid dependence and HIV disease may permit the use of HCV therapy over time.

Evolution of HCV incidence in drug users in France

Over the last 40 years, the dynamics of hepatitis C virus (HCV) infection in drug users has been affected by the illicit drug market, the health environment including the devastating impact of the HIV/AIDS epidemic which erupted in the 1980s, and the diffusion of substitution treatment beginning in 1995. The purpose of this literature review is to present the dynamics of HCV infection in drug users in France over the last 40 years. Two prevalence studies of HCV infection in the general population were conducted by the French Institute for Public Health Surveillance in 1994 and 2004 and were the touchstone data sources for this analysis. Hypotheses constructed from the findings of these two studies were examined in light of results reported by multicentre prevalence and incidence studies in drug-user populations. The incidence of HCV infection in drug users in France reached a peak in the late 1980s or early 1990s after a lengthy period of epidemic expansion. Implementation of a risk reduction policy enabled a very significant reduction in the incidence of HCV infection in drug users over the last 20 years, leading to incidence figures which are now 10–15% of the 1990 estimate.

High rates of sustained virological response in hepatitis C virus-infected injection drug users receiving directly observed therapy with peginterferon alpha-2a (40KD) (PEGASYS) and once-daily ribavirin

This retrospective study evaluated the efficacy and tolerability of directly observed therapy with peginterferon alfa-2a and once-daily ribavirin (RBV) for chronic hepatitis C in 49 opioid-addicted injection drug users (IDUs) participating in a drug treatment program at a specialized outpatient center. Patients also received prophylactic citalopram to minimize the risk of interferon-induced depression. Patients had daily access to and support from specialist physicians, nurses and counseling services at the center, and a 24-hour helpline. Sustained virological response was achieved by 48 of 49 patients (98%) overall, including 20 of 21 (95%) hepatitis C virus (HCV) Genotype 1/4-infected patients and 28 of 28 (100%) Genotype 2/3-infected patients. Treatment was well tolerated, and no unexpected side effects of peginterferon treatment were seen. The safety profile of once-daily RBV was not different from twice-daily dosing. Decline in hemoglobin levels was similar to those reported in clinical trials including once-daily RBV and did not lead to dose reduction or treatment withdrawal. Our data demonstrate that HCV-infected IDUs on stable L-polamidone (methadone) or buprenorphine maintenance can be successfully and safely treated with peginterferon alfa-2a and RBV in an optimal substitution setting.