Can Hepatitis C Virus (HCV) Direct-Acting Antiviral Treatment as Prevention Reverse the HCV Epidemic Among Men Who Have Sex With Men in the United Kingdom? Epidemiological and Modeling Insights

Abstract

Background: We report on the hepatitis C virus (HCV) epidemic among human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) in the United Kingdom and model its trajectory with or without scaled-up HCV direct-acting antivirals (DAAs).

Methods: A dynamic HCV transmission model among HIV-diagnosed MSM in the United Kingdom was calibrated to HCV prevalence (antibody [Ab] or RNA positive), incidence, and treatment from 2004 to 2011 among HIV-diagnosed MSM in the UK Collaborative HIV Cohort (UK CHIC). The epidemic was projected with current or scaled-up HCV treatment, with or without a 20% behavioral risk reduction.

Results: HCV prevalence among HIV-positive MSM in UK CHIC increased from 7.3% in 2004 to 9.9% in 2011, whereas primary incidence was flat (1.02-1.38 per 100 person-years). Over the next decade, modeling suggests 94% of infections are attributable to high-risk individuals, comprising 7% of the population. Without treatment, HCV chronic prevalence could have been 38% higher in 2015 (11.9% vs 8.6%). With current treatment and sustained virological response rates (status quo), chronic prevalence is likely to increase to 11% by 2025, but stabilize with DAA introduction in 2015. With DAA scale-up to 80% within 1 year of diagnosis (regardless of disease stage), and 20% per year thereafter, chronic prevalence could decline by 71% (to 3.2%) compared to status quo in 2025. With additional behavioral interventions, chronic prevalence could decline further to <2.5% by 2025.

Conclusions: Epidemiological data and modeling suggest a continuing HCV epidemic among HIV-diagnosed MSM in the United Kingdom driven by high-risk individuals, despite high treatment rates. Substantial reductions in HCV transmission could be achieved through scale-up of DAAs and moderately effective behavioral interventions.

Keywords: HIV; antiviral treatment; hepatitis C virus; men who have sex with men; prevention.

Figure 1.

Mathematical model schematic. The model is also stratified by treatment-naive, interferon-experienced, direct-acting antiviral–experienced, and low-/high-risk states. Human immunodeficiency virus (HIV) and non-HIV death occurs from all states. Abbreviations: Ab, antibody; HCV, hepatitis C virus; MSM, men who have sex with men.

Figure 2.

Model fits to epidemiological data from the United Kingdom. A, Number of human immunodeficiency virus (HIV)-diagnosed men who have sex with men (MSM). B, Hepatitis C virus (HCV) prevalence (antibody [Ab] or RNA positive) among diagnosed HIV-diagnosed MSM. C, HCV primary incidence among diagnosed HIV-diagnosed MSM. Solid lines show the mean value of all 1000 simulations; dashed lines show the 2.5% and 97.5% range of the projections. Black diamonds show data from Public Health England (A; model calibrated to 2013 value, other values shown for validation) and UK Collaborative HIV Cohort (B and C; model calibrated against all data points).

Figure 3.

Model projections (mean value of 1000 simulations shown) with various treatment scenarios in the United Kingdom. A, Hepatitis C virus (HCV) prevalence (antibody [Ab] or RNA positive) among human immunodeficiency virus (HIV)–diagnosed men who have sex with men (MSM). B, HCV chronic (RNA) prevalence among HIV-diagnosed MSM. C, HCV primary incidence among HIV-diagnosed MSM. Abbreviations: DAA, direct-acting antiviral; IFN/RBV, interferon/ribavirin; py, person-years; SVR, sustained virological response.

Figure 4.

Model projections of the mean number of hepatitis C virus (HCV) treatments for human immunodeficiency virus (HIV)-diagnosed men who have sex with men (MSM) in the United Kingdom for different treatment scenarios. Abbreviations: DAA, direct-acting antiviral; IFN/RBV, interferon/ribavirin; SVR, sustained virological response.