Hepatitis C elimination among people living with HIV

Background: Hepatitis C virus (HCV) is a major cause of liver-related morbidity and mortality among people living with HIV globally. Aims: The broad aim of this research was to evaluate progress towards HCV elimination among people living with HIV in Australia. Specific aims included evaluating incidence and factors associated with HCV reinfection and patterns of drug use and sexual risk behaviours after treatment and characterizing the HCV cascade of care and factors associated with engagement in HCV care among people living with HIV in Australia. Methods: In Chapter Two, the risk of HCV reinfection following successful therapy among people living with HIV was evaluated in a global systematic review and meta-analysis, with factors associated with reinfection assessed using meta-regression. In Chapter Three, patterns of drug use and sexual risk behaviours and HCV reinfection incidence were assessed before and after direct-acting antiviral (DAA) scale-up in Australia among people with HIV/HCV coinfection enrolled in CEASE. In Chapter Four, the HCV cascade of care, including HCV testing and treatment, among people living with HIV was characterized in the pre (2010–2015) and post (2016–2018) DAA era in a population-based linkage study including all people living with HIV in New South Wales, Australia with an HCV notification. Factors associated with HCV testing and DAA treatment were assessed using logistic regression. Key Findings: Globally, HCV reinfection incidence following treatment among people living with HIV was similar following interferon-based and DAA therapy, with the highest risk among men who have sex with men and those with recent HCV infection. Following unrestricted DAA access and broad treatment uptake among people living with xviii HIV in Australia, HCV reinfection incidence was low despite stable pattens of risk behaviours before and after DAA treatment. The HCV care cascade among people living with HIV demonstrated high HCV RNA testing coverage (91%) and treatment uptake following DAA availability (7% pre DAA, 73% post DAA). Younger age, female gender, and rural region of residence were negatively associated with testing; no factors were associated with DAA treatment. Conclusion: To maintain progress towards HCV elimination, ongoing HCV screening and treatment of (re)infection among people living with HIV will be required. Enabling access to and ensuring broad coverage of HCV testing, treatment and prevention will be essential.