Hepatitis C RNA prevalence before and during broad access to direct-acting antivirals in people with HIV across six countries

Background & aims Hepatitis C virus (HCV) RNA prevalence is a key measure in monitoring progress towards elimination. We estimate the effect of limited and broad availability of direct-acting antiviral (DAA) therapies on HCV RNA prevalence among people with HIV, accounting for variations in testing frequency.Methods Data from six countries of cohorts participating in the International Collaboration on Hepatitis Elimination in HIV Cohorts (InCHEHC) were included. Follow-up spanned from five years before each country's broad DAA-access date to database closure (5-8 years post-access). To address variation in HCV testing frequency, we applied a population-averaged approach to estimate HCV RNA prevalence and to quantify changes across pre-DAA access (reference), limited-access, and broad-access periods.Results Among 107,532 individuals (863,734 person-years), baseline adjusted HCV RNA prevalence ranged from 3.6% (95%CI:3.3-3.9) in the Netherlands to 11.6% (95%CI:10.8-12.4) in Italy. Relative to pre-DAAs, annual declines in RNA prevalence during limited access ranged from 6% in Italy and Spain (95%CIs:4-7% and 3-8%, respectively) to 21% in the Netherlands (95%CI:17-24%). During broad access, annual declines ranged from 7% in Spain (95%CI:5-9%) to 27% in Switzerland (95%CI:25-30%). From COVID-19 onwards, prevalence declined at a slower rate in France, Italy, the Netherlands, Spain and Switzerland, and increased in Australia. After five years of broad DAA access, prevalence ranged from 0.4% (0.3-0.5) in the Netherlands to 3.3% (2.8-3.8) in Italy.Conclusion HCV RNA prevalence was stable or slightly decreasing before DAA availability in six InCHEHC countries. After DAAs became available, substantial reductions in HCV RNA prevalence were seen among people with HIV, primarily reflecting cured chronic infections and possibly reduced transmission risk.Impact and implications Our study shows that the introduction and scale-up of direct-acting antiviral therapies led to substantial and sustained reductions in HCV RNA prevalence among people with HIV across six countries, demonstrating the population-level impact of widespread treatment access on chronic infection and potential transmission. These findings highlight the effectiveness of national DAA strategies, while also underscoring the risk of stalled progress during external disruptions such as the COVID-19 pandemic. We also show that routinely collected clinical data, when appropriately adjusted for testing patterns, can provide reliable estimates of HCV prevalence to monitor progress toward elimination targets. Sustaining high levels of testing and treatment access, particularly in lower-prevalence, post-scale-up settings, will be critical to maintaining momentum toward HCV elimination.