title: Are Interferon-Free Direct-Acting Antivirals for the Treatment of HCV Enough to Control the Epidemic among People Who Inject Drugs?
abstract: BACKGROUND
  Widely access to interferon-free direct-acting antiviral regimens (IFN-free DAA) is poised to dramatically change the impact of the HCV epidemic among people who inject drugs (PWID). We evaluated the long-term effect of increasing HCV testing, treatment and engagement into harm-reduction activities, focused on active PWID, on the HCV epidemic in British Columbia (BC), Canada.
  
  
  METHODS
  We built a compartmental model of HCV disease transmission stratified by disease progression, transmission risk, and fibrosis level. We explored the effect of: (1) Increasing treatment rates from 8 to 20, 40 and 80 per 1000 infected PWID/year; (2) Increasing treatment eligibility based on fibrosis level; (3) Maximizing the effect of testing by performing it immediately upon ending the acute phase; (4) Increasing access to harm-reduction activities to reduce the risk of re-infection; (5) Different HCV antiviral regimens on the Control Reproduction Number Rc. We assessed the impact of these interventions on incidence, prevalence and mortality from 2016 to 2030.
  
  
  RESULTS
  Of all HCV antiviral regimens, only IFN-free DAAs offered a high chance of disease elimination (i.e. Rc < 1), but it would be necessary to substantially increase the current low testing and treatment rates. Assuming a treatment rate of 80 per 1000 infected PWID per year, coupled with a high testing rate, the incidence rate, at the end of 2030, could decrease from 92.9 per 1000 susceptible PWID per year (Status Quo) to 82.8 (by treating only PWID with fibrosis level F2 and higher) or to 65.5 (by treating PWID regardless of fibrosis level). If PWID also had access to increased harm-reduction activities, the incidence rate further decreased to 53.1 per 1000 susceptible PWID per year. We also obtained significant decreases in prevalence and mortality at the end of 2030.
  
  
  CONCLUSIONS
  The combination of increased access to HCV testing, highly efficacious antiviral treatment and harm-reduction programs can substantially decrease the burden of the HCV epidemic among PWID. However, unless we increase the current levels of treatment and testing, the HCV epidemic among PWID in BC, and in other parts of the world with similar epidemiological background, will remain a substantial public health concern for many years.
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Viviane D
authors.initials: VD
authors.lastname: Lima
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Rozada
authors.affiliation: The Kirby Institute, University of New South Wales Australia, Sydney, NSW, Australia.
authors.forename: Jason
authors.initials: J
authors.lastname: Grebely
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Mark
authors.initials: M
authors.lastname: Hull
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Lillian
authors.initials: L
authors.lastname: Lourenco
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Bohdan
authors.initials: B
authors.lastname: Nosyk
authors.affiliation: Public Health Microbiology and Reference Laboratory, British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada.
authors.forename: Mel
authors.initials: M
authors.lastname: Krajden
authors.affiliation: Division of Gastroenterology, Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Yoshida
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Evan
authors.initials: E
authors.lastname: Wood
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada.
authors.forename: Julio S G
authors.initials: JS
authors.lastname: Montaner
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D001955:British Columbia / Q000453:epidemiology; D055030:Drug Users; D058872:Epidemics; D040261:Harm Reduction; D006526:Hepatitis C / Q000150:complications / Q000188:drug therapy* / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008962:Models, Theoretical; D015995:Prevalence; D015819:Substance Abuse, Intravenous / Q000150:complications*; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents